What Does One Trillion Stars Look Like? Here is an image from the Spitzer Space Telescope of our magnificent neighbor, M31, Andromeda. Recent estimates put Andromeda’s star count at one trillion. Two and one-half times greater in diameter than our own Milky Way Galaxy, Andromeda is 260,000 light-years across. She is our closest galactic companion, 2.5 million light-years distant, and is part of the Local Group, which consists of the Andromeda, Milky Way, and Triangulum galaxies. Our Miliky Way is approaching Andromeda at more than 100km per second. We can put off worrying about impact, since it will not occur for about 3 billion years. The red swaths in the image are new star formation regions of Andromeda. If only one in one billion star systems support life, then the image you are looking at here would contain 1000 alien ecosystems.



http://gallery.spitzer.caltech.edu/I...name=sig06-024

This second image is a Hubble Space Telescope photo of Andromeda’s nucleus. You can see from the photo that there are two concentrations of mass near the center. P2, the dimmer of the two concentrations, lies at the true galactic center. It is about 1.5 parsecs, or 5000 light-years, from P1. There is a black hole at the true galactic center equal to about 100 million solar masses.

I count about 3 shy of a trillion.

__________________
“The only thing necessary for the triumph of evil is for good men to do nothing” - Edmund Burke

That was actually funny.

__________________
BUSH-BASHER entoto and proud to be.

At one number per second it would take 31,709.8 years to count to one trillion.

I cheated.

__________________
“The only thing necessary for the triumph of evil is for good men to do nothing” - Edmund Burke

Recently, the Hubble Deep Field Camera studied an area of sky 0.4 degrees on a side. Over 3000 galaxies were counted. To cover the complete sky with such a slice, one would need to do it 27 million times. That means Hubble is theoretically capable of counting at least 80 billion galaxies. And that’s if its deep field camera gets no better. A few years ago, a German super computer simulation estimated that there were as many as 500 billion galaxies. At this point, no one knows an accurate estimate of the total number of galaxies, except that it is a very large number. Not all galaxies are as big as Andromeda, but you get the picture. The total number of stars is gigantic. If the average number of stars per galaxy is only 100 billion and there are only 100 billion galaxies, then there are at least 10,000,000,000,000,000,000,000 stars, and probably many more than that. What if only one in one trillion star systems supports life? Then there would be at least 10 billion alien ecosystems.