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

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!

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.

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.

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.

Planetarium Software?

On the off chance that someone following this blog has an answer for this, I'm looking for planetarium software for an online class I am developing for Fall 2008.

Minimum Qualifications

1. Cheap, or free with a good textbook


2. Works on Windows XP and Mac OSX.4


3. Ground can turn on and off


4. RA/Dec coordinates


5. Alt/Az coordinates


6. Sun and all planets


7. Messier objects


8. Ecliptic line


9. Effectively infinite time in the past and future


10. Asterisms ("constellation" connect-the-dots drawings)


11. Constellation borders (outlines)


12. I can learn it with a user's manual and/or FAQs


13. Students can learn simple tasks with hand-holding

Preferred Qualifications

1. Free


2. Works on Vista and all other platforms


3. NGC and other deep-sky objects


4. Images of objects


5. Ability to move forward in 1-day increments without showing intervening time, so as to demonstrate
   
   1. the analemma,
      
   2. which constellation the Sun is in throughout the year,
      
   3. which constellations are visible at night throughout the year,
      
   4. the motion of the planets relative to the Sun, and
      
   5. the motion of planets relative to the sky.
   
   
6. Ability to move forward in other time increments, such as a year


7. Precession


8. Ability to lock on an object (such as the Sun or Moon) while progressing time


9. Easy to learn

FWIW, Google Sky fails Minimum #9, Starry Night Pro 3.1 passes Minimum #1b but fails Minimum #2 and may fail others since I can't run it to find out, Starry Night Pro 6.2 fails Minimum 1, I suspect The Sky 6 fails Minimum 1 but I haven't done enough research to be sure, and Stellarium appears to fail Preferred 6. Some combination of Stellarium and Google Sky appears to be what I'm going to have to deal with at this point.

X-posted a few places

Asteroid 2007 WD5

Among all the hype about how asteroid 2007 WD5 has a 1 in 75 chance of hitting Mars on January 30 everyone's missing what I think is the most exciting part. According to NASA/JPL simulations it passed closed enough to Earth in early-/mid-October that our planet's own gravity is probably what actually slung it into Mars's path.

You know what's even more exciting?

We didn't discover it until November.

Science Songs

I collect science songs so I can play them for my students - sure they're college age, but who doesn't appreciate a couple F-bombs about fractals?

For the younger crowd, here's some clean ones that teach you science in 5-minute chunks. Included among them is the original version of "Why Does the Sun Shine?" (popularized by They Might Be Giants).