2007-12-06 21:44:43 · 16 answers · asked by Anonymous in Science & Mathematics ➔ Astronomy & Space
Well it took us until the twentieth century to realise that there were other galaxies. The link I've provided below should give you a good background on the whole issue, and how it came to be resolved. The Shapley-Curtis debate (aka 'The Great Debate') is a brilliant example of scientific reasoning in action.
Although Heber Curtis argued correctly that other galaxies exist apart from our own, it was the work of Edwin Hubble (of whom the HST is named) that really proved the case. It's all to do with a certain type of star called a Cepheid Variable, also known as a "standard candle" as they can be used to gauge vast distances. I won't go into the detail of exactly how the distance is calculated (it's to with the apparent versus intrinsic brightness) but they basically enabled Hubble to determine that the Andromeda Galaxy is over 2 million light years away - well outside the region of our Milky Way.
2007-12-07 01:10:15 · answer #1 · answered by Anonymous · 1⤊ 0⤋
There are many other galaxies out there. We know this because:
- We are able to see them using the HST (Hubble Space Telescope) and other ground based telescopes.
- The Universe is so vast (73,000,000,000 lightyears across for that fact) that it would not make sense to think we are the only galaxy out there.
Hope it enlightens you.
2007-12-07 02:48:29 · answer #2 · answered by Endeavour 2 · 1⤊ 0⤋
The Hubble telescope
2007-12-07 06:04:46 · answer #3 · answered by Quizard 7 · 0⤊ 0⤋
The reason is telescopes....ONLY telescopes and our eyes...
Our big telescopes like HST can look at galaxies and even stars in it and predict the properties in it!
telescopes are too powerful nowadays and large telescopes are used for only gaalaxies.
check out these images taken by HST from the solar system
http://hubblesite.org/gallery/album/galaxy_collection/
All are of galaxies.
2007-12-06 22:16:05 · answer #4 · answered by Vipul C 3 · 1⤊ 0⤋
By using telescopes to see them.And with the use of space telescopes like the hubble,spitzer,chandra,VW map and many more.
2007-12-07 05:21:20 · answer #5 · answered by ChrisCT 4 · 0⤊ 0⤋
Our sun is a star. By looking at other stars and observing the way planets move around them (like the way earth revolves around the sun), we can distinguish between other galaxies and free roaming anomalies (such as comets and asteroids).
2007-12-06 21:58:49 · answer #6 · answered by adramelke 2 · 1⤊ 1⤋
Hubble telescope.
2007-12-06 21:50:17 · answer #7 · answered by Anonymous · 3⤊ 0⤋
Well you can see them with the naked eye! One from the northern hemisphere and two from the southern.
Seeing is believing I say.
2007-12-07 09:56:42 · answer #8 · answered by Mark G 7 · 0⤊ 0⤋
By looking at them through a telescope
.,.,
2007-12-06 21:48:11 · answer #9 · answered by The Wolf 6 · 3⤊ 1⤋
We see them in telescopes, mainly.
2007-12-07 00:03:06 · answer #10 · answered by miyuki & kyojin 7 · 0⤊ 1⤋