All posts for the month February, 2006

from Digital Universe

from Digital Universe (Hayden Planetarium, American Museum of Natural History

I’ve been traveling through space on my desktop computer again. Not with the usual desktop planetarium (of which my two current favorites remain Cartes du Ciel and The Sky,) but with a very cool 3D space exploration program from the American Museum of Natural History’s Hayden Planetarium called “Digital Universe.”

Although the program may look daunting at first, the imagery and 3D exploratory ability it delivers to your desktop is worth learning to use the interface. It took me maybe an hour to figure it all out, and the documentation walked me through the process nicely. It also delivers a lot of background science to help you understand what you’re seeing and exploring.

So, sometimes I’m flying along exploring the Hyades or the galaxy’s open clusters, or I’m out there beyond our galaxy, exploring the large-scale structure of the universe. And, then it hits me — I’m checking out state-of-the-art astronomy databases on my two-year-old Dell desktop! How cool is that?

The software explores a bunch of databases, including the 2DF Survey and the Sloan Digital Sky Survey, in addition to the usual star, cluster, and nebula databases.

It’s great fun to explore, and the AMNH folks have included some helpful material for educators interested in turning their students on to the Digital Universe. Check it out!

I was wandering through the local supermarket this morning. Over the past year I haven’t been doing much of the grocery shopping since I’ve been on travel so much. So I was marveling at the sheer number of choices available on the market aisles. Who knew people needed so many choices for facial tissues? or body lotions? or varieties of cheese? or different ways to serve orange juice? I mean, you get regular, fresh-squeezed, fresh-frozen, low pulp, lots o’ pulp, low acid, low acid-no pulp, and so on. It’s truly amazing.

And, walking along in the soap aisle, I started comparing all the choices in laundry cleaners to the multiplicity of stars in the universe. There are so many kinds of laundry soap, but they all (essentially) do the same thing: clean your clothes.

Image of Milky Galaxy, courtesy of Astronomy Picture of the Day

Image of Milky Galaxy, courtesy of Astronomy Picture of the Day

Same with stars (no, they don’t keep your whites whiter and your darks darker). (And no, I’m not talking about tidal forces… ) The commonality of purpose among stars is to consume fuel in their cores during some part of their lives. That consumption is what causes stars to shine. Now, later in their lives, stars do different things (depending on their original mass). The most massive ones die as supernovae, blowing themselves to smithereens. Stars like the Sun just sort of go on until they run out of fuel and then swell up to become red giants, and then gradually shrink down to become white dwarfs. And the least-massive stars (the really small dwarfs) just shine away, locking away their elements for billions and billions and billions of years.

There is a link between stars and laundry soap that is kind of cool: if it wasn’t for stars, we wouldn’t have laundry soap. Or clothes, or bodies to wear the clothes, or a planet on which our bodies live. All the stuff we see around us had its start in a star… so think about THAT the next time you wander down the grocery store aisles pondering what brand of stuff to buy.

Step outside on a clear dark night and you see what looks like a flat backdrop of stars, looking like a dome of pinpoints overhead. It’s hard to imagine that what you’re seeing has any 3D aspect to it. Of course, everything in the universe is arrayed in three dimensions, but still, it’s a hard concept to grasp sometimes.

Explore the Universe in 3D

So, I ran across the website linked above. It gives you a 3D “feel” for the cosmos, in increasing steps and orders of magnitude out to the most distant objects ever seen. It’s way cool and you should take some time to investigate the maps.

That page led me to other cosmic mapping pages. This one takes you out through the large-scale structure of the universe by showing maps of “relatively nearby” galaxies (NOT as far as we can see, but far enough out to start to see patterns in the structure of the universe).

2Mass Views the Universe

2Mass Views the Universe

Another set of maps on the 2MASS website (2MASS stands for 2-Micron All-Sky Survey), shows the universe out to various distances, but in infrared wavelengths. You can see even more structure in these views.

As long as people have been able to stand out under the stars at night and look up, we’ve wondered about where we are and where we’re going. Cosmic mapping tells us a lot about where we are, and in fact, where other things are in the cosmos. And, we’re just now figuring out how big it all is, how fast it’s traveling, and where it’s all going. Stay tuned!