How do we know the length and the thick of our galaxy,and once more question why scientists know that our solar system lie in the edge of milky way galaxy?\n\nThanks
128966
If you look at the sky on a clear night, away from city lights and polluted air, you'll see a milky band of light right across the sky, the Milky Way, our galaxy.   With a small telescope you'll see the milkiness is made of individual stars.You're looking at the plane of ourgalaxy.   If you look away from this band of light you're looking out into intergalactic space away from the thickness of our galaxy so you don't see so many stars.   If you look in the direction of the constellation Sagittarius, you'll see the Milky Way seems to get wider and brighter.   This is the centre of the galaxy.   So the galaxy is shaped like two dinner plates facing each other, circular, and fatter at the centre than at the edges.   The centre is bright because stars are packed closer together there than way out here.   We know that we're about 30 000 light years from the centre, the diameter of the galawy is about 100 000 light years and the thickness at the centre is about 3000 light years because a particular type of star called a Cepheid variable gets brighter and dimmer with a period that depends on how bright it is.   So we know how bright it really is.   By measuring how bright it appears, we can work out haw far away it is.   So by looking at Cepheids in different parts of the galaxy we can work out its measurements.   And if we look at other galaxies outside our own, many of them are the same shape; fat in the centre, thin at the edges, with spiral arms curving out from the centre, like cloud bands in a hurricane.
642279
This question doesn't belong in the category Astronomy/Space...but in fiction.....\n\nGet real........:)
1366
The nearest galaxy is :\nCanis Major dwarf galaxy \nThe distance:\n25000 light years from the solar system \n42000 light years from the centre of the Milky Way
407208
Even the difference between space where the space station is thicker than space between the Moon and Earth which is thicker than the space between Earth and Mars which is thicker than the space between stars in the milky way which is thicker than the space between Galaxies!!!!\n\nMostly the (very small amount ~10^(-18) ATM) gas is hydrogen
138343
we have a hubble telescope. its actually a giant satellite that orbits in space. takes pictures. and sends them to computers on earth! neato!\n\nbut an intersting thing is, the pictures we get of other galaxies are what they looked like millions of years ago! thats because it takes millions of years for light to travel from THAT galaxy to THIS galaxy. :)
46598
Actually you can look at all the other stars in our galaxy and via rather simple mathematics make a point of view outside the galaxy. So, more or less, making a simple computer program for it and feeding it all the coordinates that we have on the other stars, then adding our own star as 0,0,0 and voila - a picture of the galaxy and an arrow pointing at us.
238065
Our galaxy the Milky Way contains about a hundred billion stars, there are billions of galaxies out there. I think man would be presumptious to the extreme if he believed he were the only intelligent life to exist in all of creation. I am sure with all the advances in technology, that within twenty years a signal will be picked up, that unmistakeably answers your question: We Are Not Alone!
316497
I assume you are talking about the Milky Way solar system; there are currently 28 known galaxies that I am aware of, however billions do exist.   However your statement is a flaw, while it is possible to know where the Milky Way galaxy ends and the Andromeda Galaxy or the Triangulum Galaxy begins.  An edge is also classified as a point that is very close to the outer layer of substance.  And to say what you have said is simply futlie.  Your fear of being scared should be because of your stupidity.
483918
Yes, our galaxy (and the local group) is generally heading in the direction of the virgo cluster of galaxies. All together, we are moving in the direction of a much larger structure called the 'Great Attractor' that is in the direction of the constallation of Centaurus. I'm guessing that this is what you heard about.\n\nhttp://en.wikipedia.org/wiki/Great_Attractor
585786
hows does knowing where the universe come from help you at all? the whole question is unrelevant... its exists, thats all you need to know... the probably with humanity is that we are so focused on where we came from, not where we're going...
567588
Actually you could see right through the nebula. Nebulae are extremely thin and much clearer than the air on clearest day on Earth. The only reason we can see them at all is that they are trillions of miles thick. It wouldn't be like the movies at all, where the space ship is hidden in a dense fog, it would be more like space looking clear but the stars appearing somewhat dimmer. So you could just triangulate on a number of known stars outside the nebula to determine your position.
39705
http://www.astronomycafe.net/cosm/dimens.html\n\nlong, but good explanation\n\nalso, do a search for a hypercube...you should find some interesting info there.\n\nhttp://rds.yahoo.com/_ylt=A0Je5mF.7vJDtigAKCNXNyoA;_ylu=X3oDMTE2bzk5aTlkBGNvbG8DdwRsA1dTMQRwb3MDMwRzZWMDc3IEdnRpZANGNTYxXzg4/SIG=12aalomvk/EXP=1140080638/**http%3a//www.physicsforums.com/printthread.php%3ft=16762\n\nsort of a debate on the topic, a lot of idiots speaking their mind too.  \n\n\nFor questions like this, all you have to do is a yahoo search... I wish people would stop being so lazy
45622
I don't think that fact means that it is obvious that there is other life in our universe, let alone intelligent life.  (BTW, I think you meant to say solar system instead of galaxy.  A galaxy is made up of many solar systems. )  I'd like to hope that with so many large galaxies out there that there is the possibility of one having a solar system that is capable of creating life.  If you are interested in helping search for extraterrestrial life… follow this link and join the SETI project. http://boinc.berkeley.edu/
173891
In our SOLAR SYSTEM there's just one star - the sun\n\nOur solar system is inside a galaxy called the MILKY WAY which has a total of about 300-thousand stars.\n\nThe Milky Way galaxy is in the UNIVERSE. Estimates place the total number of stars in the universe at 70-sextillion\n\nGod should be spelled B-I-G B-A-N-G\nPBrax@netscape.com
146646
Well the nearest star system is light years away. So if they send one, we won't find out the findings. Besides, how would we send commands and receive them, they would have to travel light years of distance. So I would say no.
319480
space doesn't really have limits that we'll ever reach, but yeah there are MANY others planets and solar systems in our galaxy, let alon the other 51351351354 (to the 80 trillionth power) galaxies. it's infinite.
191676
The Milky Way is moving at about 1,342,161 mph towards a galactic cluster known as Abell 3627\nhttp://answerway.com/expertans.php?category=243&expertname=Locii&catnam=Physics\n\nOur galaxy is NOT moving towards the center (or centre) of the universe. The universe has no center!\nhttp://sciastro.astronomy.net/sci.astro.9.FAQ\n\nGod should be spelled B-I-G B-A-N-G\nPBrax@netscape.com