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.
30 September 2008
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!
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