Very well done computer simulation of the evolution of a part of the universe:
Out of This World! Virtual Universe Looks Like the Real Thing
Super Model (of The Universe)
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Category Archives: Astronomy
Every 5th Star
Artist conception of the Milky Way as viewed from some distance away.
New research, based on the recently defunct Kepler Telescope, estimates there are 40 billion planets in our Milky Way galaxy that are habitable. Habitable is defined as about earth sized and in the habitable zone, where water can be a liquid.
The New York Time’s has one of the better articles on this. Check it out here: Planet Search Suggests Many Are Earth-like.
If you ask me where I feel closest to God, it’s looking at the night sky. Awe and Amazement. The two emotions I think are most appropriate when thinking about the infinite. Now there is something to add to this feeling. These numbers suggest that on average, every fifth star I see has a planet that can support life processes. That is it’s warm enough for liquid water, and the right size to hold an atmosphere but not be crushingly big.
Don’t let your imagination run too fast just yet. That could easily mean nothing more than single cell organizes. After all there is the Fermi Paradox that should caution anyway from leaping too far ahead.
The Most Amazing Sun Video I’ve Ever Seen
Check it out. This is the most amazing video I’ve ever seen of the sun. Be sure to check the size of the Earth compared to the size of the flare at 1:20.
Neutron Stars Are More Fun
So I’ve reached a new stage in my life. I’ve decided neutron stars are more fun. I know, black holes have all the buzz, the press, the hyperbole. And I know they seem absolutely necessary to make galaxies and thus life itself. But black holes seem so remote. Hardly in my universe once you cross the event horizon.
Neutron stars are still our neighbor, although very very weird neighbors. Some interesting things about them:
- Neutron stars are about 20 kilometers (12 miles) in diameter but weigh as much as 1½ to 2 suns.
- A sugar cube size of a neutron star weighs more than all humanity, or put another way, the Empire State Building would squeeze down to the size of a grain of rice on a neutron star. Remember all those pictures of atoms? The electrons whirling around the nucleus? They leave the wrong impression because the proportions are wrong in order to make the drawing work. If you hold your fists together imagining they are made of lead and are a proton and neutron, then imagine the electrons, smaller than a speck of ground pepper, whirling around 3 miles away. If you have a friend they could be doing the same thing, 6 miles away and you have an idea of what ordinary matter is like. Almost all the weight of an atom are those neutrons and protons. Now squeeze the electrons into your fists and get all your friends to hold their fists next to you and you get an idea of the what a neutron star’s matter is like. I find this an incredible image! It means almost all of what I see, including me, is really vast and empty space. (Check here to see a nice diagram of that.)
- If you could find a 1 meter (39 inch) cliff to fall off, you’d hit the “ground” at 4,300,000 miles/hour.Now that’s acceleration! At that speed you could whiz past the moon in 3½ minutes and the sun in 22 hours. (Check to see the professor’s estimates.)
- I’d weigh 35,000,000,000,000 pounds on a neutron star. I feel so grateful now that I’m so lightweight! (Click here to check your weight on different worlds.)
- To leave the star you’d have to get up to an escape velocity of about 1/3 to 1/2 the speed of light.
- If it was a special kind of neutron star, called a magnetar, the magnetism from the star would tear apart your tissues from thousands of miles away. (See the great Wikipedia for more information on this.)
- And then I’ve run across this wonderful article on the most famous neutron star in the Crab Nebula having a 4 inch carbon atmosphere.
- And most interesting to me is that, like the Earth, they can have a structure, with a crust, and different things going on inside. This is where I feel they’re still sort of vaguely familiar, as opposed to a black hole which really crosses into terra incognita. Check out Coleman Miller’s article, which is a nice summary of neutron stars.