Created as a hobby by astrophysicist Richard Powell of Great Britain, the site offer nine primary maps, each covering about 10 times the scale of the previous one. The enormity gets mind-boggling; after a while, you may want to watch an episode of Friends to counterbalance your brain. But the site really is a lot of fun, is written in a way that's mostly easy to understand, and includes many interesting facts.
For instance, as Powell explains, "Only 0.000 000 000 000 000 000 000 000 000 000 000 000 001% of the visible universe lies within our solar system. Remember that next time you pick up a book on the 'universe' and find that three quarters of it is devoted to the planets."
- The Classification Of Stars page, part of the "Universe Within 250 Light Years" section, outlines the types of stars (O, B, A, F, etc.) and spells out the differences among giant stars, white dwarfs, and supergiant stars. Included are comparisons to our sun in categories such as radius, mass, and luminosity.
- The Hertzsprung-Russell diagram, which plots the luminosity of stars.
- A list of the 200 brightest stars, including terms to feast upon, such as equatorial coordinates, galactic coordinates, spectral type, and visible magnitude.
- A map of the Hyades Star Cluster, which is the nearest major star cluster and the only one close enough to be mapped in three dimensions, the site says.
"The Universe Within 5,000 Light Years" maps our corner of the Milky Way galaxy. One interesting note: The most luminous star on the map is Rho Cassiopeia, which at 4,000 light years away appears dim to the naked eye. However, in reality, it's 100,000 times more luminous than our sun.
Multiply that times 10 and you have the next map, "The Universe Within 50,000 Light Years"--the entire Milky Way galaxy--which contains at least 200 billion stars. We're about 26,000 light years from the galaxy's center.
Included in this section is A Map Of The Milky Way, which has links to previous versions of Milky Way maps, a short history of charting the galaxy, and a chart on its properties.
By the time you get to the next map, "The Universe Within 500,000 Light Years," where satellite galaxies are charted and defined, the whole package gets pretty hard to digest. I can't help but think of Charlton Heston's monologue aboard his spaceship at the beginning of Planet Of The Apes: "Seen from here, everything seems different. Time bends, space is boundless. It squashes a man's ego. I feel lonely."
That'll be your cue to bookmark the page and come back later.
What astronomy sites do you find most interesting? Let's all become space cases in the Water Coolerdiscussion forum.