ok if we scale it down and say that earth was 1cm in diameter then how far would our universe span across in kilometers?? the galaxy we live in that is...the milky way or whatever they call it..the one that spans across 200 million light years..thanks. and how far from here to the moon in kilometers if the earth was only 1cm in diameter...thanks
2007-07-30 19:54:45 · 8 answers · asked by Anonymous in Science & Mathematics ➔ Astronomy & Space
Earth's mean radius is 6,372.797 km so let us scale it down to 1 cm, then the Moon which is a rough average of 384,000 km away, would be at 30.13 cm away and it would measure 2.7 millimeters wide.
The Sun would be 116.74 meters away and measure 2.18 meters wide.
Jupiter when closest to Earth would be at a range of 461.14 m and have a diameter of 11.21 cm.
Pluto would be at about 10.85 kilometers away and measure 1.8 millimeters wide.
You want to keep going? OK at this scale light travels at 23.537 centimeters per second. So a light year measures 7,422.62 kilometers. The closest Star is at 4.22 light years or 31,323.49 km (about thirty one thousand kilometers away)
So as the current mean radius of the Universe is about 78 billion light years, well, you do the math. I'm kidding at 1 cm=1 Earth diameter, the Universe is somewhat close to 1'157,928,720,000,000 kilometers wide.
2007-07-30 20:09:08 · answer #1 · answered by ΛLΞX Q 5 · 2⤊ 0⤋
I'll do a different scale that is much more enlightening.
Imagine the distance from the earth to the sun scaled down to one inch (2.54cm). The distance to the moon would scale to 1/400 of an inch, which is about the width of a human hair. The diameter of the earth would be 1/40 of that.
On this scale, the distance from the sun to Jupiter would be 5 inches, to Saturn a little under 10 inches and to Pluto around 39 inches(about a meter). The farthest that anything manmade has gone is the Pioneer spacecraft. It would be about 100 inches away from the sun: a little over 8 feet.
The CLOSEST star other than the sun would be 4 miles away on this scale (over 6 kilometers)! The star Sirius would be about 10 miles away. The pole star would be about 300 miles away. Most of the stars we see without a telescope at night would be closer than about 1000 miles (1600 kilometers).
The distance from the sun to the center of our galaxy would be about 25-30,000 miles. This is the distance around the earth! The Milky Way galaxy as a whole would stretch a little under half way to the moon on this scale. The closest other galaxy (the Large Magellanic Cloud) would be about 2/3 of the distance to the moon from us. The Andromeda spiral, which is the closest large spiral galaxy (like the Milky Way) would be 8 times as far away as the moon!
But these are close galaxies. Those in the VIrgo cluster would be about the distance from the sun to the planet Venus. The large scale structure of the universe would only begin to be visible when scales corresponding to the distance from the sun to Saturn are taken into account. And the farthest galaxies we have seen are about the distance that Pioneer is from the sun.
If you really want to stick with the diameter of the earth being 1 cm, multiply all of these distances by about 15,000. That would put the nearest star about 1/4 the distance to the moon!
Note: Alex Q miscalculated the light year.
2007-07-31 07:29:11 · answer #2 · answered by mathematician 7 · 0⤊ 0⤋
i find light travel time works best, without the need for converting into some other system. light travels at about 300,000 km/s. that means light can travel right around the earth in a bit over one tenth of a second. it takes light about one second to travel to the moon. eight minutes to the sun. a few hours to the outer solar system. those are everyday sort of times that scale well but now there is a big gap because it takes light over four years to reach the nearest star. the milky way galaxy is about 100,000 light years in diameter so you can see there are a lot of stars in the milky way, actually i think the sun is in a relatively sparsely populated part of the galaxy (not sure where you got 200 million light years for the size of the galaxy, that's wrong). light from soon after the big bang (the cosmic background radiation) has been travelling for about 14 billion years, which is a distance equivalent to 140,000 galaxies the size of the milky way laid end to end. however the universe has been expanding since the radiation was emitted and the radius of the visible universe is now something like 50 billion light years, i forget exactly.
2007-07-31 03:26:12 · answer #3 · answered by vorenhutz 7 · 1⤊ 0⤋
For me the significance of the size of the universe is that it is finite. It had a beginning in time, IE the big bang. And is presently limited to the size of 13.7 billion light years. Big is impressive, but it is not infinite! And I am amazed by the fact that the universe is as close as can be measured to being flat (Omega=1.02+/-.02)!
2007-07-31 03:34:39 · answer #4 · answered by skip 4 · 0⤊ 0⤋
If the Earth is a peppercorn, the Solar System (to pluto) is 1 mile across. The nearest star outside our Solar System is 1000 miles away. Going further out is just too ginormous!!!!
2007-07-31 03:02:11 · answer #5 · answered by luvlaketahoe 4 · 0⤊ 0⤋
The universe is so big, you'll hurt your head trying to conceive its exact size.
2007-07-31 04:44:58 · answer #6 · answered by Keep It 100 2 · 1⤊ 0⤋
This doesn't answer, but it's on the same page. I thought it was interesting.
http://www.youtube.com/watch?v=p86BPM1GV8M
2007-07-31 03:04:20 · answer #7 · answered by Wickwire 5 · 0⤊ 0⤋
http://www.space.com/scienceastronomy/mystery_monday_040524.html
2007-07-31 02:57:02 · answer #8 · answered by ddut2 3 · 0⤊ 0⤋