neilzero
2011-Dec-29, 12:53 AM
~Please correct the following~
Our Solar system is easily distinguished from others in our galaxy. The inner planets (Mercury, Venus, Earth and Mars) are spaced about a millionth of a light year apart. The outer planets (Jupiter, Saturn, Uranus, and Neptune) are spaced about ten times farther apart. We have found nothing from 0.005 to 4.2 light years, but we think some comets are orbiting our Sun, up to 2 light years from our sun. Likely other comets orbit the Centauri threesome up to two light years from these 3 stars which orbit each other. Possibly there are planets, but we have not found any yet. We have found some planets orbiting, some other stars, up to about 500 light years away from our Sun. This volume of space is less than one millionth of the volume of our galaxy, whose radius is perhaps 100,000 light years.
About 12 small galaxies, more or less orbit our galaxy in our local group of galaxies which includes Andromeda which is at least sightly larger than our galaxy that has the name Milky Way.
Local groups of galaxies are typically spaced at least 3 million light years apart, so there is a lot of empty space, as far as our science can tell at present, in between local groups, which have from one to a million? galaxies. The visible Universe is thought to have about 200 billion galaxies in perhaps ten billion local groups. Generally we can't identify local groups other than our own, so that ten billion may change drastically as we gather more data.
More than about 13.7 billion light years away, we think galaxies and some individual stars are receding from us at more than 186,000 miles per second = light speed, so we can't see them, and likely will never be able to see them. Possibly the unknown galaxies are a thousand times more numerous than 200,000 billion, but we will likely never know. Neil
Our Solar system is easily distinguished from others in our galaxy. The inner planets (Mercury, Venus, Earth and Mars) are spaced about a millionth of a light year apart. The outer planets (Jupiter, Saturn, Uranus, and Neptune) are spaced about ten times farther apart. We have found nothing from 0.005 to 4.2 light years, but we think some comets are orbiting our Sun, up to 2 light years from our sun. Likely other comets orbit the Centauri threesome up to two light years from these 3 stars which orbit each other. Possibly there are planets, but we have not found any yet. We have found some planets orbiting, some other stars, up to about 500 light years away from our Sun. This volume of space is less than one millionth of the volume of our galaxy, whose radius is perhaps 100,000 light years.
About 12 small galaxies, more or less orbit our galaxy in our local group of galaxies which includes Andromeda which is at least sightly larger than our galaxy that has the name Milky Way.
Local groups of galaxies are typically spaced at least 3 million light years apart, so there is a lot of empty space, as far as our science can tell at present, in between local groups, which have from one to a million? galaxies. The visible Universe is thought to have about 200 billion galaxies in perhaps ten billion local groups. Generally we can't identify local groups other than our own, so that ten billion may change drastically as we gather more data.
More than about 13.7 billion light years away, we think galaxies and some individual stars are receding from us at more than 186,000 miles per second = light speed, so we can't see them, and likely will never be able to see them. Possibly the unknown galaxies are a thousand times more numerous than 200,000 billion, but we will likely never know. Neil