NASA released a report on the final few minutes of the Space Shuttle Columbia disaster. They concluded that it was impossible for the astronauts to survive the breakup at the altitude at which it occurred - they had a list of specific failures in the suits (as well as other places) that occurred, but even without those failures the astronauts would not have made it, unfortunately. However, with this information, they will be able to build the next generation of ships and spacesuits that much better.
Edit:
You can find the full 400-page report and a video from inside the Shuttle (around a minute of length, at the start of them hitting atmosphere, not including the disaster) at this link.
30 December 2008
24 December 2008
Calendric woes
We're having a leap second this year at New Year's. The atomic clocks will briefly read "11:59:60 pm" (after reading "11:59:59 pm") Dec 31, before finally rolling over to 12:00:00 am, January 1.
One of my close high school friends says her birthday is the Ides of March (March 15), but it's really the 15th day of the 3rd month in the Chinese calendar. She was born in China, in the third month of their calendar, on the 15th day of that calendar, so when they emigrated they put down our third month (March) and 15th day (March 15, the Ides of March, per Julius Caesar fame). However, the luni-solar calendar doesn't start on our January 1, it starts (IIRC) two New Moons after Winter Solstice - which is usually early February or occasionally late January. So the date she was born according to the Western solar calendar (what we use in the USA) was "actually" sometime around early April through mid May. What date her Chinese birthday falls on will then vary every year, since our calendars are not in sync. Hence the simplicity of just saying it's the Ides of March every year.
And if you got that explanation of mine, try out this explanation of when Sir Isaac Newton's birthday should be.
One of my close high school friends says her birthday is the Ides of March (March 15), but it's really the 15th day of the 3rd month in the Chinese calendar. She was born in China, in the third month of their calendar, on the 15th day of that calendar, so when they emigrated they put down our third month (March) and 15th day (March 15, the Ides of March, per Julius Caesar fame). However, the luni-solar calendar doesn't start on our January 1, it starts (IIRC) two New Moons after Winter Solstice - which is usually early February or occasionally late January. So the date she was born according to the Western solar calendar (what we use in the USA) was "actually" sometime around early April through mid May. What date her Chinese birthday falls on will then vary every year, since our calendars are not in sync. Hence the simplicity of just saying it's the Ides of March every year.
And if you got that explanation of mine, try out this explanation of when Sir Isaac Newton's birthday should be.
22 December 2008
"Shattering the Glass Closet"
If you think women in science have it hard, what about gays and lesbians in science? (It's a long article, but well-written.)
Science Concerns Survey
If you've got a few minutes to spare, please fill out this survey by the National Academies of Science.
05 December 2008
12 November 2008
As if Texas weren't dommed enough
...one of their Board of Education members has gone on record saying that "Barack Obama is plotting with terrorists to attack the U.S." Source
08 November 2008
Obama: candidate for skeptics
Obama had my vote from the minute McCain called a multi-million dollar planetarium an "overhead projector." Palin clinched it when she said that fruit-fly research was pointless, a sentiment echoed when McCain dissed bear research. But now, Obama has my heart too. When asked in an interview if he'd spoken to any ex-presidents,
*giggles*
...he responded that he had spoken to all former presidents "that are living... I didn't want to get into a Nancy Reagan thing about, you know, doing any seances." --CNN
*giggles*
30 October 2008
Hubble's Back Up!
As evidenced by the below image!
On the left is what looks nearly like a normal spiral - except that the spiral has been distorted by the interaction into a ring. And also the center is bluer than normal, indicating star formation where usually the core has more older stars and star formation occurs mainly in the spiral arms. To the right is the second interacting galaxy, which is a distorted mess of blue where new stars have been triggered to form from the interaction, and a blob of colder dark gas blocking our view somewhat where it appears reddened.
On the left is what looks nearly like a normal spiral - except that the spiral has been distorted by the interaction into a ring. And also the center is bluer than normal, indicating star formation where usually the core has more older stars and star formation occurs mainly in the spiral arms. To the right is the second interacting galaxy, which is a distorted mess of blue where new stars have been triggered to form from the interaction, and a blob of colder dark gas blocking our view somewhat where it appears reddened.
Outside the Universe?
One of my friends over on LiveJournal asked what's outside the universe. Thought it'd be fun to post my response here and see what y'all think.
The current model of the universe says that there isn't an "outside" to it in that if you keep going in one direction you can "leave" the universe. It's like if you look at a map of the Earth and ask what's past the edge - the Earth is round so you just come back to the other side of it. We're not convinced that our universe is finite in size (and therefore loops back on itself) or if it's instead infinite.
However, when you look at the flat map of the Earth, what that map fails to show is that since the Earth is a sphere, you *can* leave the Earth. If you could leave the universe, our best guess right now (via string theory) is that there are multiple "higher dimensional" universes called branes (short for membranes) that intersect to form universes like ours. So if we had hyperdimensional eyes, we'd see a bunch of sheets that cross each other, and at each crossing is another universe. I'm not sure if this idea is testable yet, or if it's still just a pipe dream though.
29 October 2008
iPhone Astronomy
iPhone-based astrophotography is begun. Below is an image of Jupiter taken by an iPhone through an 8" Meade Cassegrain telescope by amateur astronomer Mike Weasner.
Note that on the right you can see three of the moons of Jupiter - this is similar to what Galileo saw when looking through his small 2" refracting telescope, hence the four largest moons are dubbed the Galilean moons in his honor. Continued observations of Jupiter over the course of days, months, and even years led Galileo to the realization that they were orbiting Jupiter, not the Earth, and therefore the Earth was not the center of the universe.
Another thing you can see in this image is that the face of Jupiter has bands across it. Galileo could not see these himself, but he saw other "irregularities" or deviations from perfection on the Moon (craters), Saturn (rings, which he couldn't identify as such), and Venus (phases, like we see our Moon go through naked-eye). These other features also helped support Galileo's claim that the universe was NOT perfect, and did NOT revolve around the Earth. Rest assured if he had seen stripes on Jupiter, he would have recorded such a fact.
So this little iPhone image is better than what the father of modern astronomy saw himself.
For more information on this image and the telescope used, see also:
* Bad Astronomy (Dr. Phil Plait)
* The Mac Observer (John Martellaro)
* Weasner's Mighty ETX Site (Mike Weasner)
* Meade Telescopes, LX200-ACF model
Note that on the right you can see three of the moons of Jupiter - this is similar to what Galileo saw when looking through his small 2" refracting telescope, hence the four largest moons are dubbed the Galilean moons in his honor. Continued observations of Jupiter over the course of days, months, and even years led Galileo to the realization that they were orbiting Jupiter, not the Earth, and therefore the Earth was not the center of the universe.
Another thing you can see in this image is that the face of Jupiter has bands across it. Galileo could not see these himself, but he saw other "irregularities" or deviations from perfection on the Moon (craters), Saturn (rings, which he couldn't identify as such), and Venus (phases, like we see our Moon go through naked-eye). These other features also helped support Galileo's claim that the universe was NOT perfect, and did NOT revolve around the Earth. Rest assured if he had seen stripes on Jupiter, he would have recorded such a fact.
So this little iPhone image is better than what the father of modern astronomy saw himself.
For more information on this image and the telescope used, see also:
* Bad Astronomy (Dr. Phil Plait)
* The Mac Observer (John Martellaro)
* Weasner's Mighty ETX Site (Mike Weasner)
* Meade Telescopes, LX200-ACF model
28 October 2008
To any Texan readers:
I know there's a couple of you who read me. The Gov of Texas has just appointed a 6-person committee to revamp the state's K-12 science curriculum. One of these six individuals is a creationist. A second person on the committee is not just any ol' creationist, but the director of the US's biggest creationist organization: Stephen C. Meyer, director of the Discovery Institute. And the chair of the committee is Donald McLeroy, who has gone on record as saying that biology textbooks containing evolution are anti-Christian and anti-American.
If you give a shit about this, there's more info on astronomer Phil Plat's blog along w/ more links. Unfortunately the only one who can change this situation is the governor, and he's in power until 2010, but perhaps you guys can make his life a little more difficult.
If you give a shit about this, there's more info on astronomer Phil Plat's blog along w/ more links. Unfortunately the only one who can change this situation is the governor, and he's in power until 2010, but perhaps you guys can make his life a little more difficult.
Labels:
activism,
badastronomy,
creationism,
evolution,
ID,
phil plait,
politics
27 October 2008
Stephen Hawking to retire
Stephen Hawking is facing a mandatory retirement clause at Cambridge University at the end of the year. But we all know that good physicists don't ever quit, they just go emeritus, stop teaching, and do research full time.
19 October 2008
Hubble Update
NASA has started the switchover process to Side B - it turns out I was a bit fuzzy in my understanding before. The two "sides" are not the power source, they're computers that interpret commands from Mission Control, and send data back down to the ground. Either way, Hubble can't take any data while this equipment is down. Because it's actually a computer, and the process of switching from one to the other is complex, they haven't tested Side B since it was launched - why mess with a good thing as long as Side A was working. So during the process of switching over, they hit a snag, though they haven't detailed what the problem is. Time will tell how easily they'll fix it. At the worst, the next Shuttle Servicing (I think it's scheduled for February?) could bring a whole new "side" up and fix the problems.
In the meantime, many astronomers are losing their time on the Hubble. It's my understanding that if you lose your time, you have to reapply for more time in the future, but you tend to get a high priority if that's the case. (This is a similar process to how it works if you're on a land-based telescope and you get clouded out.) There are a few projects that have guaranteed time, and they essentially get a percentage of the functional HST time, so for any time that the HST is down they just lose their time. The people/institutions who "own" that time can choose to reschedule as they wish.
In the meantime, many astronomers are losing their time on the Hubble. It's my understanding that if you lose your time, you have to reapply for more time in the future, but you tend to get a high priority if that's the case. (This is a similar process to how it works if you're on a land-based telescope and you get clouded out.) There are a few projects that have guaranteed time, and they essentially get a percentage of the functional HST time, so for any time that the HST is down they just lose their time. The people/institutions who "own" that time can choose to reschedule as they wish.
16 October 2008
The tricky question of "what is science?"
Linking here to a third-hand blog post about how scientists often can't define terms like "theory" and "law." No wonder the media gets them mixed up! Part of the problem though is that scientists don't study how they do science, they just do it. Studying how science is done would be part of epistemology (the study of how we know things), which is part of philosophy. It's also in the realm of science education - but unfortunately science educators also don't know how science works... *grumble* No wonder things like ID and the Moon Hoax have managed to make such inroads into our culture!
13 October 2008
IR Photography
This weekend I was playing around with an infrared filter on my digital camera, and realized that the resulting photos could help illustrate some points in astronomy.
Different types of light are important in astronomy, as they are tracers for different processes and temperatures inside the objects we're looking at. Since we can never go to most of the objects we study, it's crucial that we get as much information as we can from light alone. For example, IR light is good for studying cold objects, and for studying objects that are hidden inside a cloud of dust.
Take a look at the three photos below. They are (in order) normal visible light as our eyes see it, a black and white version of what our eyes normally see (visible light), and an infrared image (displayed in black and white). (Click on the images for bigger versions.)
Notice how in the last image, the water and the sky appear darker. This means that they are not sending as much IR light towards the camera as they are sending visible light. Specifically, this is the same reason as the sky is blue: light from the Sun comes in all colors. Red light (and infrared light) tends to go straight through the Earth's atmosphere. Blue light, however, gets scattered by dust in the air, so as a result the whole sky looks blue. Since the red light goes straight through, this is also why at sunset the Sun looks red. Since the IR light goes straight through as well, when we look at the sky in IR light, we do not see the IR light from the Sun scattered throughout the sky, so the sky looks dark. Lakes look bright blue because the blue light of the sky is then reflected back at our eyes, so in IR lakes and rivers would also appear dark. Note however, that the clouds on the horizon of the IR image do appear bright - the high water content in these clouds does scatter the IR light back towards the camera.
Similarly, IR light goes right through thin clouds in space (just like it goes through our atmosphere), but it does eventually get stopped by thicker clouds (just like the clouds on the horizon in the last image). Because of this, we have to use radio waves to see through the densest clouds. And also because of the clouds and moisture on Earth, we cannot actually do sensitive IR imagery from the ground, and have to instead do it from very high mountaintop observatories (above much of the Earth's atmosphere), or from space telescopes like Spitzer.
Different types of light are important in astronomy, as they are tracers for different processes and temperatures inside the objects we're looking at. Since we can never go to most of the objects we study, it's crucial that we get as much information as we can from light alone. For example, IR light is good for studying cold objects, and for studying objects that are hidden inside a cloud of dust.
Take a look at the three photos below. They are (in order) normal visible light as our eyes see it, a black and white version of what our eyes normally see (visible light), and an infrared image (displayed in black and white). (Click on the images for bigger versions.)
Notice how in the last image, the water and the sky appear darker. This means that they are not sending as much IR light towards the camera as they are sending visible light. Specifically, this is the same reason as the sky is blue: light from the Sun comes in all colors. Red light (and infrared light) tends to go straight through the Earth's atmosphere. Blue light, however, gets scattered by dust in the air, so as a result the whole sky looks blue. Since the red light goes straight through, this is also why at sunset the Sun looks red. Since the IR light goes straight through as well, when we look at the sky in IR light, we do not see the IR light from the Sun scattered throughout the sky, so the sky looks dark. Lakes look bright blue because the blue light of the sky is then reflected back at our eyes, so in IR lakes and rivers would also appear dark. Note however, that the clouds on the horizon of the IR image do appear bright - the high water content in these clouds does scatter the IR light back towards the camera.
Similarly, IR light goes right through thin clouds in space (just like it goes through our atmosphere), but it does eventually get stopped by thicker clouds (just like the clouds on the horizon in the last image). Because of this, we have to use radio waves to see through the densest clouds. And also because of the clouds and moisture on Earth, we cannot actually do sensitive IR imagery from the ground, and have to instead do it from very high mountaintop observatories (above much of the Earth's atmosphere), or from space telescopes like Spitzer.
05 October 2008
MESSENGER flies by Mercury tonight
MESSENGER, the latest mission to Mercury, makes its second fly-by of the planet tonight. Keep your eyes peeled for articles online with the new pictures in the morning!
Let's see what the astrologers have to say about this one (considering that Mercury's in retrograde, yadda yadda).
Let's see what the astrologers have to say about this one (considering that Mercury's in retrograde, yadda yadda).
Aurorae
This weekend, if you live in more Northern climes, keep your eyes peeled for the Northern lights (or Southern if you live more southerly). As we come more into solar maximum, they should become more common. Aurorae are caused by charged particles from the Sun interacting with the Earth's magnetic field, much like a current in a fluorescent bulb interacts with the ionized gas inside. As we approach solar maximum, the Sun is more likely to throw off loops of material in a solar flare, like in the below picture.
If there is enough material, and it's sent in the right direction (towards Earth), then in a few days it'll get to us and we'll have a chance of Northern lights! Because of how the Earth's magnetic field is shaped, they tend to happen towards the poles, so if you live in Canada chances are you've seen them, and if you live in Florida chances are you never will.
If there is enough material, and it's sent in the right direction (towards Earth), then in a few days it'll get to us and we'll have a chance of Northern lights! Because of how the Earth's magnetic field is shaped, they tend to happen towards the poles, so if you live in Canada chances are you've seen them, and if you live in Florida chances are you never will.
Labels:
aurora,
northern lights,
solar activity,
solar maximum,
Sun
30 September 2008
News outlets starting to understand electric car drawbacks
I was pleasantly surprised upon reading this article about converting hybrid cars to electric plug-ins that CNN is finally starting to acknowledge that electric cars are not the be-all end-all solution some people think they are.
The problem is that the electricity has to come from somewhere, and right now around 70% of the electricity in the US comes from fossil fuels (50% from coal burning, even). It's *better* than using gasoline though for a few reasons - such as that remaining 30% that comes from water, wind, solar, and nuclear (which technically is also non-renewable, but does not have the greenhouse gas problems of fossil fuels instead adding disposal problems). In addition there is economy of scale in power plants - rather than having a small engine and generator inside the car, power plants have a number of large ones. These tend to be much more efficient in terms of both higher power output compared to fuel input, and also lower pollution output compared to fuel input. Because of both of these higher efficiencies, the energy from plants tends to cost less than the energy from gasoline.
So in the end, yes it's good to change your car to electric only, but you will still be paying a higher electricity bill in the place of a gasoline bill, and it's NOT a perfect solution as of yet. Fuel cell cars also aren't a perfect solution, but with more research we'll continue to improve our options.
The problem is that the electricity has to come from somewhere, and right now around 70% of the electricity in the US comes from fossil fuels (50% from coal burning, even). It's *better* than using gasoline though for a few reasons - such as that remaining 30% that comes from water, wind, solar, and nuclear (which technically is also non-renewable, but does not have the greenhouse gas problems of fossil fuels instead adding disposal problems). In addition there is economy of scale in power plants - rather than having a small engine and generator inside the car, power plants have a number of large ones. These tend to be much more efficient in terms of both higher power output compared to fuel input, and also lower pollution output compared to fuel input. Because of both of these higher efficiencies, the energy from plants tends to cost less than the energy from gasoline.
So in the end, yes it's good to change your car to electric only, but you will still be paying a higher electricity bill in the place of a gasoline bill, and it's NOT a perfect solution as of yet. Fuel cell cars also aren't a perfect solution, but with more research we'll continue to improve our options.
Labels:
electricity,
energy,
fossil fuels,
fuel efficiency,
greenhouse
Hubble problems
The Hubble Space Telescope is currently dead. The electrical circuit that controls ALL the cameras on the telescope, called Side A, has ceased functioning. The HST also cannot send any data. It can however be pointed in different directions (for what purpose though?), and can otherwise communicate with mission control. The HST also has a backup circuit, called Side B, that can provide power to the cameras - everything on these ships is built with multiple redundancy, even when they're serviceable. Unfortunately Side B hasn't been tested in orbit in the 18 years Hubble's been up - we knew Side A was working, so why mess with a good thing? (It did test out good before launch though.) They're currently working on switching over to Side B, but it may take a few days if all goes well, or a few months if not.
Meanwhile the servicing mission for mid-October has been put on hold. If they're not able to bring Side B online, I'm sure they will alter the postponed mission's objectives to start with fixing either Side A or B, or possibly installing a Side C, whichever seems easiest.
Meanwhile the servicing mission for mid-October has been put on hold. If they're not able to bring Side B online, I'm sure they will alter the postponed mission's objectives to start with fixing either Side A or B, or possibly installing a Side C, whichever seems easiest.
27 September 2008
Tablet PC advice?
I'm looking to buy a tablet PC for work. The models I've seen good reviews of are Lenovo Thinkpad, HP Pavilion, and Fujitsu LifeBook. What I want in one, in order of priority is as follows.
Specifically I will be using the tablet to give a presentation in PowerPoint, which I'll be annotating with the stylus, while running Camtasia (screencasting software, which records what's presented on the screen along with an audio track). I will then need to render the Camtasia recording and post it online. Camtasia's a memory-hog, hence the first three items on my list.
I have a $3,000 budget limit, and the money's not mine, so I'm looking for the best I can get.
Got any advice for me, or links to reviews?
- Dual-core processor
- High RAM
- Windows XP
- Sturdy and reliable
- Lightweight
- 5 hour battery life
- Large hard drive
Specifically I will be using the tablet to give a presentation in PowerPoint, which I'll be annotating with the stylus, while running Camtasia (screencasting software, which records what's presented on the screen along with an audio track). I will then need to render the Camtasia recording and post it online. Camtasia's a memory-hog, hence the first three items on my list.
I have a $3,000 budget limit, and the money's not mine, so I'm looking for the best I can get.
Got any advice for me, or links to reviews?
26 September 2008
24 September 2008
"What your vote helps determine"
In case you're wondering where your research dollars go, and what difference your vote makes...
US Citizens, register to vote by early October.
US Citizens, register to vote by early October.
20 September 2008
And while we're nit-picking...
"[CERN spokesman] Gillies said the sector that was damaged will have to be warmed well above the absolute zero temperature used for operations so repairs can be made, a time-consuming process."
(emphasis mine)
CNN/AP article
1.9K is as far from absolute zero as 0.999c is from the speed of light. Neither absolute zero nor the speed of light are actually reachable. It's like saying "the winds from Hurricane Ike were infinitely strong" or "gasoline prices today were infinitely high." Neither of those are true, and doesn't get across the real information that would let people prepare properly. Similarly, saying that the LHC operates at absolute zero or at the speed of light just misses the point and is shoddy reporting.
Thanks for the many responses to my last post guys! Even if you don't agree with my perspective, I appreciate it when people take the time to think about the science involved, and where the language of science is different from everyday English. I'm hoping to make a post to address a couple points people made specifically, but don't hold your breath on it b/c I've got to write a few quizzes and grade some labs this weekend.
18 September 2008
More bad science
More bad science from CNN/AP:
"...a statement by CERN, as the organization is known." Any reason to not give what CERN stands for, or at least what the organization is?
"The Large Hadron Collider was launched September 10, when scientists circled a beam of protons in a clockwise direction at the speed of light." While "launched" may be a poor choice of words, "at the speed of light" is outright WRONG, and shows that the author has a complete lack of understanding of the concepts "speed of light."
"...a statement by CERN, as the organization is known." Any reason to not give what CERN stands for, or at least what the organization is?
"The Large Hadron Collider was launched September 10, when scientists circled a beam of protons in a clockwise direction at the speed of light." While "launched" may be a poor choice of words, "at the speed of light" is outright WRONG, and shows that the author has a complete lack of understanding of the concepts "speed of light."
09 September 2008
LHC goes live!
The Large Hadron Collidor goes online today! This is as exciting as the day Hubble opened its shutters May 20 1990.
Even a lot of sciencey people I know have been asking about what the LHC is, and why the doomsayers are wrong, so here's a little summary of it. Particle accelerators (as is the LHC) are devices that smash things together to find out what's inside them. It's somewhat like if we wanted to learn how cars work, so we did head-on crash tests. While the analogy isn't perfect (no analogy ever is), there are some similarities. For example, while head-on crashes in real life are dangerous, crash tests are completely controlled and are entirely safe. Particle accelerators let us learn about what's going on inside small particles. Older lower energy ones smashed together "normal" particles like electrons and protons and helped us to learn that those are made of quarks. The LHC is a high energy one and we'll be smashing together another type of particle called a hadron, and it will help us learn how the entire universe works, for example gravity and dark matter.
The woo-hoos (aka tinfoil hat wearers) have been saying doom and gloom about the LHC, claiming that the high energy levels will either rip a hole in the entire universe, or else create a black hole that will swallow the Earth. Well, there's really no reason to worry at all. First off, we only call the LHC "high energy" by comparison - it's higher energy than anything people have been able to do before now. However, much higher energy collisions take place every second as cosmic rays hit the Earth's atmosphere. The main difference is that in the LHC these collisions are controlled. As I said to a biologist in another community, being afraid of that is kinda like if people were afraid of scientists culturing e.coli - it happens in the wild, after all, and that's not scary at all.
Even a lot of sciencey people I know have been asking about what the LHC is, and why the doomsayers are wrong, so here's a little summary of it. Particle accelerators (as is the LHC) are devices that smash things together to find out what's inside them. It's somewhat like if we wanted to learn how cars work, so we did head-on crash tests. While the analogy isn't perfect (no analogy ever is), there are some similarities. For example, while head-on crashes in real life are dangerous, crash tests are completely controlled and are entirely safe. Particle accelerators let us learn about what's going on inside small particles. Older lower energy ones smashed together "normal" particles like electrons and protons and helped us to learn that those are made of quarks. The LHC is a high energy one and we'll be smashing together another type of particle called a hadron, and it will help us learn how the entire universe works, for example gravity and dark matter.
The woo-hoos (aka tinfoil hat wearers) have been saying doom and gloom about the LHC, claiming that the high energy levels will either rip a hole in the entire universe, or else create a black hole that will swallow the Earth. Well, there's really no reason to worry at all. First off, we only call the LHC "high energy" by comparison - it's higher energy than anything people have been able to do before now. However, much higher energy collisions take place every second as cosmic rays hit the Earth's atmosphere. The main difference is that in the LHC these collisions are controlled. As I said to a biologist in another community, being afraid of that is kinda like if people were afraid of scientists culturing e.coli - it happens in the wild, after all, and that's not scary at all.
05 September 2008
C-14 anomalies and solar fluctuation
So you know how you learned in high school about carbon dating be a super reliable way of measuring the age of things, since the amount of C-14 in organic material decreases at a steady rate?
They lied.
The amount of (mildly) radioactive Carbon-14 in organic materials does slowly decrease. But exactly how slowly or quickly depends upon two additional factors: how much C-14 is present in the atmosphere around that sample, and how much the C-14 is also triggered to decay. And fascinatingly, it turns out that the Sun of all things influences both of those!
Specifically the Sun's neutrino output. Neutrinos are high energy but low mass particles that the Sun creates in the process of nuclear fusion. When these particles collide with Nitrogen-14 in the atmosphere, they cause the N-14 to convert to C-14. Therefore if there's more neutrinos coming out from the Sun than usual, we'll have more C-14 than usual, so C-14 will appear to decay more slowly than usual, so in order to get a large amount of decay we'd need a super-large amount of time, so (if we assumed it was decaying at the same rate as usual) we would be estimating times too short.
On the other hand, there's a competing effect too. C-14 naturally decays, however it can be stimulated to decay faster, and in fact neutrinos can do this too. So if htere's more neutrinos coming from the Sun, C-14 will be decaying faster than usual, so to get a large amount of decay we'd need only a small amount of time, so (if we assumed it was decaying at the same rate as usual) we would be estimating times too long.
Now here's what's interesting. If we compare the ages of trees based upon carbon dating to their ages based upon tree rings, we can try and calibrate the rate of C-14 decay to what's really happening. While the authors of the linked paper didn't specify which of the two effects dominated (that is, it's unclear to me if excess neutrinos would result in MORE or LESS C-14 overall, and thus over- or underestimate the ages of trees using C-14), they did say that there's a 200-year period to the "anomalies" in carbon-dating results as compared to tree rings. So if the anomalies are caused by the Sun's neutrino output, that means that the Sun's nuclear fusion (which creates the neutrinos) is varying on a 200-year cycle.
Why hello, Mr. Variable Star!
They lied.
The amount of (mildly) radioactive Carbon-14 in organic materials does slowly decrease. But exactly how slowly or quickly depends upon two additional factors: how much C-14 is present in the atmosphere around that sample, and how much the C-14 is also triggered to decay. And fascinatingly, it turns out that the Sun of all things influences both of those!
Specifically the Sun's neutrino output. Neutrinos are high energy but low mass particles that the Sun creates in the process of nuclear fusion. When these particles collide with Nitrogen-14 in the atmosphere, they cause the N-14 to convert to C-14. Therefore if there's more neutrinos coming out from the Sun than usual, we'll have more C-14 than usual, so C-14 will appear to decay more slowly than usual, so in order to get a large amount of decay we'd need a super-large amount of time, so (if we assumed it was decaying at the same rate as usual) we would be estimating times too short.
On the other hand, there's a competing effect too. C-14 naturally decays, however it can be stimulated to decay faster, and in fact neutrinos can do this too. So if htere's more neutrinos coming from the Sun, C-14 will be decaying faster than usual, so to get a large amount of decay we'd need only a small amount of time, so (if we assumed it was decaying at the same rate as usual) we would be estimating times too long.
Now here's what's interesting. If we compare the ages of trees based upon carbon dating to their ages based upon tree rings, we can try and calibrate the rate of C-14 decay to what's really happening. While the authors of the linked paper didn't specify which of the two effects dominated (that is, it's unclear to me if excess neutrinos would result in MORE or LESS C-14 overall, and thus over- or underestimate the ages of trees using C-14), they did say that there's a 200-year period to the "anomalies" in carbon-dating results as compared to tree rings. So if the anomalies are caused by the Sun's neutrino output, that means that the Sun's nuclear fusion (which creates the neutrinos) is varying on a 200-year cycle.
Why hello, Mr. Variable Star!
Labels:
astronomy,
carbon dating,
earth science,
geoscience,
radioactivity,
science
25 August 2008
Evolution in the classroom
An interesting NY Times article follows a science teacher who worked on evolution standards throughout a few days in his classroom. There's also a bunch of links to graphics and more information, such as the infamous 10 Questions About Evolution - and answers!
22 August 2008
US News Best Colleges
The US News and World Report yearly college rankings are out. You can view the lists, or search on the college of your choice.
19 August 2008
Another Pop Quiz
This one by Dr. Richard Mueller of UC Berkeley and "Physics for Future Presidents" fame, and brought to you by the NY Times. If you enter there, I'd be curious to hear your answer here as well.
Pop Quiz!
I heard someone's cellphone go off, so it's time for a pop quiz. Or if you prefer, think of it as a thought experiment. It's two questions. Answer me the best that you can, and explain your reasoning.
1) A tunnel is drilled straight through the Earth, straight from one side to the other and through the core. Let's suppose the tunnel is given strong enough walls that it doesn't collapse, and that it's well insulated so it isn't too boiling inside. A tourist sees this gigantic hole and decides "hey, there's no bottom to hit, so it's gotta be safe to jump into it," and follows word with deed. (a) Where does he end up? (b) If he could stop at the middle, what would be his weight there (as compared to his weight standing on the surface)?
2) Same tunnel through the Earth, this time you can walk along it with a barometer, reading air pressure throughout the tunnel. When you get to the center, will the air pressure be greater than that at the surface, the same, less than the surface, or entirely zero?
1) A tunnel is drilled straight through the Earth, straight from one side to the other and through the core. Let's suppose the tunnel is given strong enough walls that it doesn't collapse, and that it's well insulated so it isn't too boiling inside. A tourist sees this gigantic hole and decides "hey, there's no bottom to hit, so it's gotta be safe to jump into it," and follows word with deed. (a) Where does he end up? (b) If he could stop at the middle, what would be his weight there (as compared to his weight standing on the surface)?
2) Same tunnel through the Earth, this time you can walk along it with a barometer, reading air pressure throughout the tunnel. When you get to the center, will the air pressure be greater than that at the surface, the same, less than the surface, or entirely zero?
18 August 2008
Famous Scientists
I was amused to stumble across the website Famous Scientsts while doing Google Image Labeler. They've got mini-bios and photos of some 20 scientists, and I was glad to see there's two women in the list.
More on UC vs Christian schools
Whee, CNN Video now allows embedding!
(If the video has problems, try this link.)
The girl's statement that her school teaches the "theories" of both ID and evolution and therefore is less "narrow" is exactly the problem - ID is not a theory, it's a baseless conjecture without any evidence. A theory needs to be well-tested, with an overwhelming amount of physical evidence to support it, such that it is well-accepted by the scientific community. These students are clearly NOT being taught that crucial distinction, and therefore do NOT understand how science works.
(If the video has problems, try this link.)
The girl's statement that her school teaches the "theories" of both ID and evolution and therefore is less "narrow" is exactly the problem - ID is not a theory, it's a baseless conjecture without any evidence. A theory needs to be well-tested, with an overwhelming amount of physical evidence to support it, such that it is well-accepted by the scientific community. These students are clearly NOT being taught that crucial distinction, and therefore do NOT understand how science works.
15 August 2008
Bizarre observations from normal videos
There's a couple videos making the rounds right now where a woman observes some natural phenomenon and makes really bizarre conclusions. Although these are posted by two different people, I believe they were originally made by the same person - the rainbow link is a reposting, the Moon one appears to be the original person if you glance at some of her other videos, but I don't see the rainbow among them.
The Rainbow DiHydrogen Monoxide Conspiracy
This was discussed by the Bad Astronomer, and I didn't have the desire to view it then, but will now. If anyone here really does need an explanation of this "freaky unnatural rainbow sprinkler, since light isn't naturally a rainbow," in short, whenever there's a fine mist (such as clouds, or spray from a waterfall, or from a sprinkler) in front of you, and a source of continuum light (usually the Sun) behind you, the light bounces around inside the mist droplets and comes back out as a rainbow. A similar effect can be seen with ice particles in clouds around the Moon at night - since it's ice, the way the light bounces is different so you'll see the ring around the Moon instead of in the opposite direction.
The statement "This cannot be natural, it didn't happen 20 years ago," is simply an indication that 20 years ago she was not as observant as she is now, and in fact if she had been listening in school 30 years ago, she might even know "what the hell is going on".
The Moon is Broken
What's happening to the Moon in this video is known as earthshine. The Moon appears bright because light from the Sun bounces off the Moon and into our eyes. If you were standing on that part of the Moon you'd see a bright Sun in the sky. The other side appears dark usually b/c no light is bouncing off of it. Sometimes we can actually see the "dark" side due to reflected light from the Earth - light from the Sun bounces off the Earth, then off the Moon and into our eyes. If you were standing on the Moon there you'd see a bright Earth in the sky, much like the Full Moon looks bright to us here.
As for her last comment in the video ("The Moon seems awfully low for this time of year"), it's not actually the time of year that matters, it's the phase of the Moon. The crescent Moon is never far from the Sun in the sky, so it makes perfect sense for the waxing crescent Moon to set right after sunset.
While this woman's conclusions are entirely bizarre, I have to applaud her observational skills, and her desire to learn what caused these various effects. There are many more people out there with even more bizarre ideas in their heads, but they never bother to look up or around themselves, and thus have no hope of ever leaving their strange little worlds. This woman at least has a chance.
The Rainbow DiHydrogen Monoxide Conspiracy
This was discussed by the Bad Astronomer, and I didn't have the desire to view it then, but will now. If anyone here really does need an explanation of this "freaky unnatural rainbow sprinkler, since light isn't naturally a rainbow," in short, whenever there's a fine mist (such as clouds, or spray from a waterfall, or from a sprinkler) in front of you, and a source of continuum light (usually the Sun) behind you, the light bounces around inside the mist droplets and comes back out as a rainbow. A similar effect can be seen with ice particles in clouds around the Moon at night - since it's ice, the way the light bounces is different so you'll see the ring around the Moon instead of in the opposite direction.
The statement "This cannot be natural, it didn't happen 20 years ago," is simply an indication that 20 years ago she was not as observant as she is now, and in fact if she had been listening in school 30 years ago, she might even know "what the hell is going on".
The Moon is Broken
What's happening to the Moon in this video is known as earthshine. The Moon appears bright because light from the Sun bounces off the Moon and into our eyes. If you were standing on that part of the Moon you'd see a bright Sun in the sky. The other side appears dark usually b/c no light is bouncing off of it. Sometimes we can actually see the "dark" side due to reflected light from the Earth - light from the Sun bounces off the Earth, then off the Moon and into our eyes. If you were standing on the Moon there you'd see a bright Earth in the sky, much like the Full Moon looks bright to us here.
As for her last comment in the video ("The Moon seems awfully low for this time of year"), it's not actually the time of year that matters, it's the phase of the Moon. The crescent Moon is never far from the Sun in the sky, so it makes perfect sense for the waxing crescent Moon to set right after sunset.
While this woman's conclusions are entirely bizarre, I have to applaud her observational skills, and her desire to learn what caused these various effects. There are many more people out there with even more bizarre ideas in their heads, but they never bother to look up or around themselves, and thus have no hope of ever leaving their strange little worlds. This woman at least has a chance.
Judge says UC can deny religious course credit
(08-12) 17:25 PDT SAN FRANCISCO -- A federal judge says the University of California can deny course credit to applicants from Christian high schools whose textbooks declare the Bible infallible and reject evolution.
Rejecting claims of religious discrimination and stifling of free expression, U.S. District Judge James Otero of Los Angeles said UC's review committees cited legitimate reasons for rejecting the texts - not because they contained religious viewpoints, but because they omitted important topics in science and history and failed to teach critical thinking.
(Bob Egelko, SF Chronicle)
This is excellent news for science and history, for universities, and for students. For science and history because it promotes fact-based and logic-based teaching, saying that making assumptions before performing the research is NOT an acceptable method of analysis. For universities because we can continue to defend our rigorous standards without government or religious interference. And for students because students will continue to be delivered quality higher education requiring them to learn critical thinking skills which will serve them well in life, and hopefully parochial K-12 schools will begin to reconsider their courses which do not teach such skills.
12 August 2008
Partial Lunar Eclipse: Aug 16
On the heels of last week's total solar eclipse, this Saturday night, August 16, there will be a partial lunar eclipse, visible in New England, South America, Africa, Europe, and parts of Asia. Sorry rest of the US, you don't get to see it.
Lunar eclipses often precede or follow solar eclipses because a solar eclipse requires the Earth, Moon, and Sun to be very precisely lined up, with the Moon in the middle. This precise condition doesn't last very long, maybe a couple weeks, but fortunately that's how long it takes for the Moon to go around to the other side, so we now have Moon, Earth, Sun.
I also mentioned this phenomena here, or you can Google on eclipse season or line of nodes for more info.
Lunar eclipses often precede or follow solar eclipses because a solar eclipse requires the Earth, Moon, and Sun to be very precisely lined up, with the Moon in the middle. This precise condition doesn't last very long, maybe a couple weeks, but fortunately that's how long it takes for the Moon to go around to the other side, so we now have Moon, Earth, Sun.
I also mentioned this phenomena here, or you can Google on eclipse season or line of nodes for more info.
Labels:
astronomy,
eclipses,
links,
lunar eclipse,
solar eclipse
22 July 2008
Science Ads
There is something seriously wrong with science ads these days.
"Boom De Ya Da" (ad for the Discovery Channel)
"epMotion" (ad for Eppendorg automatic pipetting machine)
"'The PCR Song' by Scientists for Better PCR" (ad for Bio-Rad PCR [DNA analysis] machine)
"Boom De Ya Da" (ad for the Discovery Channel)
"epMotion" (ad for Eppendorg automatic pipetting machine)
"'The PCR Song' by Scientists for Better PCR" (ad for Bio-Rad PCR [DNA analysis] machine)
17 July 2008
Plastic Bag Yarn
I just saw an interesting idea for "Reduce, Reuse, Recycle": plastic bag yarn! Instructions on how to make it are here, and some examples of final products are here.
Now, I'm not a big knitter or crocheter, but I think making such "yarn" could be fun, so I'm curious if anyone would buy the yarn to make their own things out of. What do you think?
X-posted to Zandperl's Fancies
Now, I'm not a big knitter or crocheter, but I think making such "yarn" could be fun, so I'm curious if anyone would buy the yarn to make their own things out of. What do you think?
X-posted to Zandperl's Fancies
02 July 2008
Science in DC
This week I'm in Washington DC for the annual meeting of my teacher's union - yes higher ed professionals are unionized too, especially the ones in public higher ed. I've had three interesting science sightings.
- The DC Dental Spa has advertisements all over the Metro stations. Click through to that and look in the upper left. Look familiar?
- Further down the same platform, I saw ads for the Spy Museum sporting photos of the Very Large Array. I wasn't able to Google a picture of their actual ad, nor snap one in the Metro (anti-terrorism security and all that), but the ad had a shot much like this one with the colors altered to yellow and red tones, and the very strong implication that the dishes were intended for communications with spy satellites. (And yes I'm sure it was the VLA - I always examine the pedestals for the three feet since when I visited Socorro, NM, that was the easiest part for us to see other than when I got to walk out on the face of one.)
- And the last interesting sighting: in the Vendor Exhibition Hall of the NEA convention I saw a giant model T-Rex head. Delighted at the prospect of literature saying how evolution is a great tool to teach about the Scientific Method and critical thinking, I instead discovered that it was a booth by the Creation Museum. (No I'm not linking to them to drive up their traffic - if you really care, they're the first Google hit.) I am planning to tomorrow bring my camera and get a picture in front of the booth, just because I have to. It'll be funnier than my Segway shot.
Labels:
creationism,
education,
evolution,
science,
spitzer
21 June 2008
Ohio: Not quite doomed
The Bad Astronomer is fond of the phrase "State: Doomed" in the context of State approving creationism in the classroom. He'd probably be happy to hear that Ohio is not doomed, or at least only a little doomed.
An Ohio school is firing a middle school science teacher for the joint sins of teaching creationism in the science class (including keeping a Bible on his desk), and burning a cross into a student's arm. Shame it took the student abuse for the other part to surface.
An Ohio school is firing a middle school science teacher for the joint sins of teaching creationism in the science class (including keeping a Bible on his desk), and burning a cross into a student's arm. Shame it took the student abuse for the other part to surface.
09 June 2008
Plant sensing
Plants may not have brains, but some new work shows that they may have a sense of smell that can let a parasitic creeper pick the most hospitable host from others surrounding, and let other plants choose to invade the root space of "unrelated" plants within the same species while not competing with their "relatives." Bizarre.
03 June 2008
Greenhouse calculator
Made by the Aussies, it's a greenhouse gas calculator - it determines how much CO_2 you produce in a year (3 tonnes per year per person is the sustainable amount, 24 is the average Aussie), and therefore when you should kill yourself so you don't use more than your fair share.
I produce 15.0 tonnes of CO_2 per year (according to their calculator), and therefore I should die at age 15.4. At least I'm better than average! :-P
I produce 15.0 tonnes of CO_2 per year (according to their calculator), and therefore I should die at age 15.4. At least I'm better than average! :-P
Labels:
earth science,
environment,
global warming,
greenhouse,
science,
yoinked
Browser preview
For your entertainment, here's a service that allows you to preview your blog in multiple different browsers. Here's what I got for this blog:
30 May 2008
Evolution of a Clock
I believe this is from the same guy who did the white and black evolution demo. In this one, he takes the strawman argument of the "blind watchmaker" and turns it around: the argument is a flawed analogy, as there is no driving force or limiting factors in actual watchmaking the way there is in evolution - random mutations, and natural selection. The author introduces these to factors into a pile of gears and hands, and watches what happens.
As you watch this nearly 10 minute long video, it may help to hover your mouse near the pause button, as some of the text goes by quickly.
As you watch this nearly 10 minute long video, it may help to hover your mouse near the pause button, as some of the text goes by quickly.
26 May 2008
European Fuel Economy
Now this's interesting. I'd always heard that European cars in general get higher fuel efficiency than US cars, so I looked it up briefly. Wikipedia, for example, says that a typical European car gets 47 mpg highway, 36 mpg city [Wikipedia: Gas mileage]. But then I checked the Smart Fortwo specifically, since it's got such horrible gas mileage. The exact same model of car the EU rates as 50 mpg while the US rates it as 36 mpg [Wikipedia: Smart Fortwo].
This makes me question our testing methods, and whether European cars really do get better gas mileage than ours. I mean, if we don't test things the same way, it's comparing apples and oranges. Anyone know more about this?
This makes me question our testing methods, and whether European cars really do get better gas mileage than ours. I mean, if we don't test things the same way, it's comparing apples and oranges. Anyone know more about this?
16 May 2008
Science questions
On another blog a few interesting questions were asked of scientists by a school board member. My responses are below. I'd love to see others' thoughts, whether responses to the original questions, or what you think of mine.
1. What or who sparked your interest in science?
If I had to say a person, it'd be my Dad - an electrical engineer who encouraged me to take VCRs apart and always told me I could do anything I wanted to do. If I had to say an event, it was going to an observatory in CT (I grew up in NYC) at age 12 and seeing Saturn through a telescope.
But more realistically, it was a process that took years throughout high school in which I realized that I enjoyed it and was good at it. I also enjoyed Latin and Art, but I wasn't as good at them (and there's no money in the fields). I was also good at Math but didn't enjoy it. It was when I took Physics that every thing clicked - I finally understood why Math had been invented.
2. What does the word "science" mean to you?
a) A process of inquiry in which one asks questions and gathers physical evidence to attempt to find an answer based in physical reality. Sometimes the Scientific Method is used, but while it is the most famous description of the process, it is not the only one.
b) A set of "facts" about the physical universe, which are frequently updated as humanity learns more.
3. What scientific skills do you most often use in your work?
In the spirit of full disclosure, I am currently a community college faculty member, not a research scientist, however these skills come to me through my scientific background. The most important skill I have is to take a set of isolated facts, internalize and process them, and recombine them into a coherent picture of reality that I can then communicate to others. Communication skills are high on my list - I have often been praised for my writing ability and my attention to detail, in addition to oral communication (of course, as a teacher).
4. What do you think makes a good science teacher?
Nowadays K-12 science teachers need to have excellent critical thinking skills and be able to distinguish between pseudoscience (such as astrology, creationism/ID, mercury/autism, Moon Hoax conspiracy theory) and actual science (the real things being astronomy, evolution, vaccinations, space exploration).
5. Do you think children have enough science preparation for today's world?
No. Science standards are being continually eroded through the introduction of deceptive "teach the controversy" rules (when there isn't any controversy at all in the scientific subject). Students are encouraged to have poor critical thinking skills, and to alternately fear and mock science and scientific thought. I especially worry about the fate of girls in science - middle school is where we tend to lose them to social pressures.
6. If there was one science concept that you could ensure all children learn, what would it be?
Content: Evolution. (And I'm a physicist.) Without understanding evolution, there's no way they can understand humanity, let alone medicine.
Process: Critical Thinking.
Second choice on content would be alternative energy sources and conservationism in general - and that's also interdisciplinary.
7. What are some of teh science trends you predict for the future?
* International sanctions against the US for our carbon emissions - oops, that's political!
* The continued decoding of the genome will lead to leaps and bounds in medicine.
* The definition of "planet" will be revised yet again when the International Astronomical Union meets next in 2009. The New Horizons mission to Pluto and other Kuiper Belt Objects will reach Pluto in 2015 and I'm not sure when after that it will get to other Kuiper Belt Objects. Expect Pluto and the definition of planet to stay in the news until at least 2020.
8. What can teachers do to encourage more women/minorities to consider science careers?
* Bring in women scientists to give speeches
* Hang posters of women scientists in classrooms/halls
* Feature women scientists in class, such as Marie Curie, Rosalind Franklin, and the Harvard College Observatory women.
* Start after school activities targeting girls in science - many colleges and universities run these programs partnering with area K-12 schools, and organizations such as the NSF and NIH offer grants to both K-12 schools and higher ed organizations for them.
* Hire and support teachers and administrators who will aggressively pursue and follow through such grants and collaborations.
* Hire teachers with both education and science backgrounds - either without the other won't do as much good as having both.
12 May 2008
The Wage Gap in the Sciences
According to the 2004 US Census, women in the US earned on average 76.5¢ for every dollar that men earned. (Wikipedia) This statistic, however, is misleading as it fails to take into account issues such as choice in career (CEO pays more than cashier), education, delay of career due to childcare, or even full/part time employment status (correct me if I'm wrong on this last one). While the statistic of 76.5¢ on the dollar is quite depressing, it would be much more useful to compare like jobs and like education levels.
Well, the National Science Foundation (NSF) has a series of statistics that help us to examine exactly this! If you look at the overall situation, then it's worse than in non-science fields: Women in the sciences earn $49k on average, while men earn $70k, putting women at 70¢ on the dollar ("Median annual salary of scientists and engineers employed full time, by highest degree, broad occupation, age group, and sex: 2003", Table H-16). But once you start to control things better, the situation isn't quite as dire. For people with a Master's degree such as myself, women earn 80¢ on the man's dollar ("Primary education/employment status and median salary of 2001 and 2002 S&E master's degree recipients, by field, sex, race/ethnicity, and disability status: 2003", Table H-14).
It varies by field and age as well. Women in Biological/Life sciences can expect 88¢, while women in Math average out at 71¢ (lower than the national average!). My field, physical science, is nearly as bad at 73¢ - however young women (under age 29) can expect to make $1.14 to every dollar that a man makes! How's that for breaking the curve! Unless she's got a doctorate too, then it's back down to 72¢.
07 May 2008
The Eye's Evolution
Latest from the National Center for Science Education is a video about the evolution of eye. This video is a very simple explanation of why the irreducible complexity argument for the eye is flawed. The answer: it isn't irreducibly complex!
Labels:
creationism,
evolution,
ID,
intelligent design,
links,
science,
videos,
youtube
06 May 2008
More poor science in the news
My goodness, is this CNN video misleading. The person who wrote this video is trying to make the point that older cars get better gas mileage than newer cars, when in fact the reality is that he's just supporting the known fact that smaller cars get better gas mileage than bigger cars. In both cases the person interviewed traded down in car size when they went to the older car - one guy went from an SUV to a smaller pickup truck, the other from a pickup truck to a sedan. Whoever wrote this article needs to go back to college and take a science course where they teaching about controlling the variables.
05 May 2008
Newest New Moon!
If I'm understanding this correctly, the newest New Moon ever has been photographed - it's a new record!
04 May 2008
Kepler College
Thanks to Matt for the link - I didn't even know that there was a whole college on astrological studies, Kepler College. Thankfully they're non-accredited, though they are authorized by the state of Washington to award degrees.
This means that (1) thankfully we don't have to waste time trying to get them unaccredited since they already are, and (2) I have to do more research to understand the distinction between accreditation and authorization. I suspect that the former means an independent national board of experts essentially peer-reviews the school, while the latter is just a small legal issue having to do primarily with paperwork but also with state educational boards voting (though not necessarily using any expert witnesses and detailed review).
Oh and, anyone else get a chuckle out of the school being named "Kepler"?
This means that (1) thankfully we don't have to waste time trying to get them unaccredited since they already are, and (2) I have to do more research to understand the distinction between accreditation and authorization. I suspect that the former means an independent national board of experts essentially peer-reviews the school, while the latter is just a small legal issue having to do primarily with paperwork but also with state educational boards voting (though not necessarily using any expert witnesses and detailed review).
Oh and, anyone else get a chuckle out of the school being named "Kepler"?
03 May 2008
Sexism against women physicists
Anyone have access to this article? It looks to be an interesting read, but I can't access it from home.
02 May 2008
29 April 2008
ID and religion
I know there's a few readers of this blog who believe differently from how I do on "hot topic" issues such as global warming, Intelligent Design, and conspiracy theories. For those of you who believe in Intelligent Design, I'm curious, do you feel that ID is creationism and is a religious belief, or do you think it is a scientific theory with tangible proof to support it?
24 April 2008
One small step for Texans
Today a subcommittee of the Texas Higher Education Coordinating Board has decided unanimously that the non-accredited Institute for Creation Research, which espouses Young Earth Creationism, may not offer an online Master's of Science degree, saying that while "Science and religious belief are surely reconcilable, ... they are not the same thing."
Boo-yah!
It's worth noting though that this is not the final word. Next the full TX HECB must meet and agree with the committee decision. Presuming they agree with the subcommittee, the ICR can still fight it many ways. But for now reason appears to be winning.
Follow-up to this post
Boo-yah!
It's worth noting though that this is not the final word. Next the full TX HECB must meet and agree with the committee decision. Presuming they agree with the subcommittee, the ICR can still fight it many ways. But for now reason appears to be winning.
Follow-up to this post
21 April 2008
Magic Pen
Next time you need some procrastination, check out the "crayon physics" -style java game Magic Pen. Your goal on every level is to get a circle (or sometimes a square) to move to touch a flag. You do this via drawing simple physics-type tools. The one thing it's lacking is a pause button, that would really help.
If you ever get stuck on a level, you can skip it via the menu, but you cannot submit your "score" (number of shapes used) until you beat all levels. Once you beat all 25 levels (took me a full day of procrastination), go back and see how many different ways you can solve the same level. After a bit you'll build up a mental "toolbox" of different techniques for each level, and you can go back and see how to force a square peg into a round hole.
If you ever get stuck on a level, you can skip it via the menu, but you cannot submit your "score" (number of shapes used) until you beat all levels. Once you beat all 25 levels (took me a full day of procrastination), go back and see how many different ways you can solve the same level. After a bit you'll build up a mental "toolbox" of different techniques for each level, and you can go back and see how to force a square peg into a round hole.
02 April 2008
Globular Cluster or Dwarf Galaxy
A few years back when doing research on the mass of dwarf galaxies I asked my advisor what the difference was between a globular cluster and a dwarf galaxy. I was more-or-less scoffed at, as the "obvious" textbook answer is that globulars consist of only old stars and don't have any gas, while galaxies of any sort will have stars of varying ages and will have gas.
New research using Hubble and Gemini South shows the question isn't quite as clear-cut as textbooks like to put it. Our Milky Way galaxy has all these globular clusters orbiting it, but we've also got some dwarf galaxies like the Large and Small Magellenic Clouds. There's this one strange globular cluster, Omega Centauri, which has got multiple generations of stars and a large mass (causing its fast spin), but doesn't seem to have any gas. And now they've discovered that there's an intermediate mass black hole in the center, implying that that Omega Centauri is probably a dwarf galaxy, not a globular cluster after all. Huh, go figure.
New research using Hubble and Gemini South shows the question isn't quite as clear-cut as textbooks like to put it. Our Milky Way galaxy has all these globular clusters orbiting it, but we've also got some dwarf galaxies like the Large and Small Magellenic Clouds. There's this one strange globular cluster, Omega Centauri, which has got multiple generations of stars and a large mass (causing its fast spin), but doesn't seem to have any gas. And now they've discovered that there's an intermediate mass black hole in the center, implying that that Omega Centauri is probably a dwarf galaxy, not a globular cluster after all. Huh, go figure.
30 March 2008
Is this conscious action?
In the below video (8:28), a visitor at a zoo records an elephant paint a picture, apparently a self-portrait of elephant with flower.
This begs the question to me: is the elephant aware of what she is painting? She definitely is deliberate about her actions, it's not just a case of putting random splotches on a paper that humans then interpret as a picture. But the question is whether she understands that it's a drawing of an elephant, or if to her it's a random pattern of lines that she has learned produces praise from the audience and treats from her keepers. If we saw creativity (that is, variations of the picture), that might lean me towards thinking it's conscious action with understanding, but then again elephants are remarkable creatures and perhaps she is capable of memorizing dozens of patterns that result in rewards.
Paintings are not, in my opinion, reliable Turing tests for animal intelligence.
This begs the question to me: is the elephant aware of what she is painting? She definitely is deliberate about her actions, it's not just a case of putting random splotches on a paper that humans then interpret as a picture. But the question is whether she understands that it's a drawing of an elephant, or if to her it's a random pattern of lines that she has learned produces praise from the audience and treats from her keepers. If we saw creativity (that is, variations of the picture), that might lean me towards thinking it's conscious action with understanding, but then again elephants are remarkable creatures and perhaps she is capable of memorizing dozens of patterns that result in rewards.
Paintings are not, in my opinion, reliable Turing tests for animal intelligence.
29 March 2008
"Earth Hour"
Tonight, Saturday March 29, there is a movement called "Earth Hour." From 8 to 9pm tonight (in your local time zone), turn your lights out to help raise awareness of energy conservation. To me this's a win-win situation - by 8pm it's dark out. If everyone really does turn their lights out, it'll make the night skies that much darker (though yes, I know streetlights won't be out) and that much better for observing! T$ points out that it isn't going to be all that effective since we can still leave on computers and TVs - which are probably a bigger power drain for most modern families. But it's better than nothing.
28 March 2008
Help me understand a misconception....
An interesting situation came up in my Physics class today, where two of my students surprised me with a question they asked. To try and understand their thinking so I can teach the content better, I'd like to ask that everyone take a look at the below situation and tell me what you think will happen. I don't care if you know any physics or if you're a professional ear-wax taster, I want to know what you think and why.
In the picture below, Box 1 (m1) is hanging from a string that passes over a pulley. There's no friction in the pulley, and the pulley has no mass, so it can spin freely. The string is then connected to Box 2 (m2) sitting on a table. For simplicity, let's assume there's no friction on the table - there's some lubrication between the box and the table.
Open this page in a new window or tab to fill out the poll - there's 6 short questions (check boxes) about how the blocks will move.
X-posted a couple places.
In the picture below, Box 1 (m1) is hanging from a string that passes over a pulley. There's no friction in the pulley, and the pulley has no mass, so it can spin freely. The string is then connected to Box 2 (m2) sitting on a table. For simplicity, let's assume there's no friction on the table - there's some lubrication between the box and the table.
Open this page in a new window or tab to fill out the poll - there's 6 short questions (check boxes) about how the blocks will move.
X-posted a couple places.
20 March 2008
Crayon Physics
I've been wanting a tablet PC for a while now, and this game (page currently lagging) only reinforces it. In case the page won't load, here's a review of it, and below is a demo.
I've seen tools like these accompanying textbooks before, but unfortunately never had one with a book that I chose. I should write to a few publishers to see if they have demos I can download. Unlike this "game" version, they're generally designed to accompany a Physics I course, so students can explore physical situations without friction, or so that students can perform online labs. (I'm curious about doing online labs and wish to explore the possibilities, but I will take a lot of convincing before I'm willing to do it.)
I've seen tools like these accompanying textbooks before, but unfortunately never had one with a book that I chose. I should write to a few publishers to see if they have demos I can download. Unlike this "game" version, they're generally designed to accompany a Physics I course, so students can explore physical situations without friction, or so that students can perform online labs. (I'm curious about doing online labs and wish to explore the possibilities, but I will take a lot of convincing before I'm willing to do it.)
17 March 2008
04 March 2008
Y Baad Speeling Iz Gud
Stolen from a friend of mine, who stole it from elsewhere.
And because I'm who I am (physicist and daughter of an English teacher), I just had to reply...
* 0. Stop spelling correctly before it's too late! | 03/04/2008 07:41:42 PM UTC
The Daye Aftur Tumurrow: Y Baad Speeling Iz Gud
Recently, I've seen many people on the internet trying to correct others' spelling. Unfortunately, in doing so, you are endangering the lives of every good person on earth.
As you all know, Earth rotates on its axis, giving us day and night and stopping any portion of earth from freezing or incinerating. What you may not know is that the primary driving force of this rotation is English teachers. More precisely, English teachers rolling in their graves. Thanks to conservation of angular momentum, for a teacher to spin one way forces Earth to spin the other way. Our ENTIRE EXISTANCE depends on these teachers! To clarify the point, here is a diagram:
But how, you ask, could this possibly be related to the internet? As it turns out, teacher grave-spinning is fueled by only two sources: 1st grade essays, and the Internet. Unfortunately for us, 1st grade spelling has rapidly improved in the last decade, leaving the internet as the only source of terrible spelling. For each idiot on the internet, one teacher spins, and this effect has increased over the past decade to become the only force keeping our planet alive. Misuses of there/they're/their and you're/your are especially potent, and account for over 90% of the Earth's rotational velocity.
Why do you care? Because your life depends on it. I put out as a call to all mankind, PROMOTE BAD SPELLING! It is the only thing between us and a horrible, barren world where everything good is dead. For example, consider the following image (it may be shocking to some, parental consent is advised for young children). The red areas are burnt to a crisp, the blue areas are at roughly -42 Kelvin, and only the yellow portions survive.
To prevent the horrific image just pictured, you must forget the grammar and spelling you have learned. Still, if you choose to continue in your rash action, please at least slow down the damage you cause by including the following in your signature. The repeated posting of such content should be enough to allow those truly willing to solve the problem to do so.
Q u o t e:
Their they're, an tey hav there lewt w/thm. Your so dum you're brane is leik a peenut.
Thank you for reading this, and please, consider the future of humanity when you post.
And because I'm who I am (physicist and daughter of an English teacher), I just had to reply...
For completeness, I must point out that there is actually a secondary source of angular momentum: living English teachers rolling their eyes. However, this is a second-order effect for two reasons. Firstly, angular momentum depends upon the mass and the radius of the object (L=mvr), and eyes are both less massive (m) and smaller (r) that entire bodies, so each individual eye will have less of an effect than each individual body.
Secondly, although it is wel known that teachers (of which English teachers are a subset) have eyes in the backs of their heads (resulting in 4-8 eyes per teacher, depending on whether they wear glasses on any of said eyes), there are stll many fewer living English-teacher eyes than dead English-teacher bodies.
Combining these two reasons, the angular momentum from living English teachers rolling their eyes is expected to be more than four orders of magnitude smaller than the angular momentum from dead English teachers rolling in their graves, and therefore can be safely ignored for the purposes of this argument.
Your Astrological Career!
The Chronicle of Higher Education as a *stellar* article on how to find the best career after college - no more of those fancy schmancy personality tests, instead counselors should just ask your sign.
Took me three readings of the intro/closing paragraphs to figure out that it was tongue-in-cheek, despite my *knowing* the Chronicle wouldn't espouse pseudo-science. Have I mentioned I'm not too good at dry humor?
And my ideal career? Academe! :-P
...or astrologer...
Took me three readings of the intro/closing paragraphs to figure out that it was tongue-in-cheek, despite my *knowing* the Chronicle wouldn't espouse pseudo-science. Have I mentioned I'm not too good at dry humor?
And my ideal career? Academe! :-P
Aquarius: (January 21-February 19) Like all Aquarians, you are unique. You have the celestial gifts of depth and foresight; you are the shaper of new paradigms. You are probably the voice of your generation. Everyone likes you and thinks you are beautiful, kind, and progressive. You are reluctant to stay in one place for too long: You need your freedom to be who you are, and many other places need to benefit from your wisdom and generosity. To Kill a Mockingbird is your favorite book and movie. Above all, you want to help people, and there is nowhere that they can hide in the long run. Of course, you don't want to be the "tool" of any kind of "institution," but you also know that the children are our future. Consider a degree in ethnomusicology, education, women's studies, ecology, or social work. Once you've grown beyond academe, consider expanding your horizons as a community activist, organic farmer, folk artist, co-op worker, weaver, basement gardener, or astrologer.
...or astrologer...
29 February 2008
Creationists' Science Ed Master's
And I *still* say that an online Master's of Science Ed degree from the Institute for Creation Research is worth the paper it's printed on.
Follow up here
Follow up here
19 February 2008
Total Lunar Eclipse Weds Feb 20
I keep forgetting to mention, there's a total lunar eclipse tomorrow night, Weds Feb 20, 2008. It's got great visibility too: North America from Texas to the East Coast, all South America, West Africa, and Europe from Germany on West. It starts at around 8:43pm for those of us on the East Coast.
Here's what I recommend for a sane person to view it. Go out around 8:35pm (or the equivalent for your time zone) dressed warmly (layers - Bulky is Beautiful!), and bring a camera or tele if you have but it's not needed. Watch until you get cold (5-15 minutes). Go inside for 15 minutes to a half hour. Repeat until done, making sure to come out 5 minutes before the other times listed in this image for the most interesting parts to view.
Clear skies!
Here's what I recommend for a sane person to view it. Go out around 8:35pm (or the equivalent for your time zone) dressed warmly (layers - Bulky is Beautiful!), and bring a camera or tele if you have but it's not needed. Watch until you get cold (5-15 minutes). Go inside for 15 minutes to a half hour. Repeat until done, making sure to come out 5 minutes before the other times listed in this image for the most interesting parts to view.
Clear skies!
18 February 2008
Earth-like Planets commonly form, says Spitzer study
Spitzer (the "IR Hubble") scientists have recently put out an interesting paper implying that the majority of Sun-like stars may form Earth-like planets. (Hat tip to the Bad Astronomer for the head's up.) They studied a set of 300 Sun-like stars and the dust around them - dust glows in the infrared, so Spitzer easily sees it.
The color and brightness of the glowing indicate the temperature of the dust. The temperature of the dust is only (essentially) affected by the light from the parent star, so the temperature depends on the distance from the star. So by looking at each star, even though they can't actually resolve the disks they can from the *color* of the disk determine how the dust is distributed around the star.
Next thing they did is determined the age of the stars.I'm less clear on how that was done, since Never mind, I read the actual article (PDF), and they say "Ages for these stars were estimated from pre-main sequence evolutionary tracks, as well as kinematic association with groups of known age (e.g. Mama jek et al. 2002)." I'm actually a little skeptical about this, since those methods also rely on the color and brightness of the star/disk (since we cannot resolve the two separately), so it seems like circular reasoning to me. I ended up posting a question about this on the Bad Astronomy blog to see if I can get any response.
However, let's move on. Assuming they know the disk description, and assuming they know the age of the star, and they selected stars that are all like the Sun, they can then track how the disk changes with the age of the star. They clearly find that the disk thins out at an Earth-like orbital radius as the star ages. One possible explanation of this is that an Earth-like planet formed and cleared out the dust (by accreting it). It's also possible that the dust was just blown out by the stellar wind, but I am under the impression that the study ruled this out - that dust around and Earth orbit is preferentially dissipating as the star ages, not that all dust is dissipating which would be the result of a stellar wind.
So the conclusion: nearly all Sun-like stars form Earth-like planets. Very interesting. We have yet to *see* these planets, but there's evidence they may exist.
The color and brightness of the glowing indicate the temperature of the dust. The temperature of the dust is only (essentially) affected by the light from the parent star, so the temperature depends on the distance from the star. So by looking at each star, even though they can't actually resolve the disks they can from the *color* of the disk determine how the dust is distributed around the star.
Next thing they did is determined the age of the stars.
One thing I'm skeptical about is the method they used to determine the age of the stars. For the most part the stars and the disks cannot be resolved. They get information about the disk from the IR spectrum of the star/disk combination. They get the age of the stars (according to the actual paper) from evolutionary tracks on the HR diagram - which rely upon the spectrum of the star/disk combination. Isn't there some circular reasoning there? Or are the evolutionary tracks based upon the visual spectrum and we're able to assume the visual wavelengths are entirely uncontaminated by the disk?
However, let's move on. Assuming they know the disk description, and assuming they know the age of the star, and they selected stars that are all like the Sun, they can then track how the disk changes with the age of the star. They clearly find that the disk thins out at an Earth-like orbital radius as the star ages. One possible explanation of this is that an Earth-like planet formed and cleared out the dust (by accreting it). It's also possible that the dust was just blown out by the stellar wind, but I am under the impression that the study ruled this out - that dust around and Earth orbit is preferentially dissipating as the star ages, not that all dust is dissipating which would be the result of a stellar wind.
So the conclusion: nearly all Sun-like stars form Earth-like planets. Very interesting. We have yet to *see* these planets, but there's evidence they may exist.
Labels:
astronomy,
earth science,
extrasolar planets,
spitzer
24 January 2008
Evolution Demo
This video demonstrating a simple version of natural selection and evolution is 10 minutes long.
Unfortunately I don't think this video is likely to convince creationists of the veracity of evolution - they will just complain that the code isn't right or something, but perhaps it will make a difference with the fence-sitters.
Unfortunately I don't think this video is likely to convince creationists of the veracity of evolution - they will just complain that the code isn't right or something, but perhaps it will make a difference with the fence-sitters.
Subscribe to:
Posts (Atom)