2006-09-20 08:09:20 · 21 answers · asked by Anonymous in Science & Mathematics ➔ Astronomy & Space
Depends if you mean large galaxies of comparable size to the Milky Way or dwarf galaxies orbiting the Milky Way.
And the other issue is: do you mean nearest to our position within the Milky Way or nearest to the Milky Way as a whole or nearest to its galactic centre?
Large galaxies: Andromeda Galaxy (barred spiral galaxy) (M31) and Triangulum Galaxy (spiral galaxy) (M33) are the two nearest. M31 is larger than the Milky Way and M33 is smaller.
M31 is at a distance of 2.52±0.14 million light years away, Recent observations by the Spitzer Space Telescope revealed that M31 contains one trillion (10^12) stars, greatly exceeding the number of stars in our own galaxy. It has a radius of 69,600 ± 3,900 light years.
M33 is only minimally further away at a distance 2.59 million light years and has a radius of 27,000 light years. It is of about average size, compared to most spiral galaxies in the universe.
All three are members of The Local Group. This is the name given to the group of galaxies that includes our galaxy, the Milky Way. The group comprises over 30 galaxies, with its gravitational center located somewhere between the Milky Way and the Andromeda Galaxy.
The galaxies of the Local Group cover a 10 million light-year diameter. The group resides in the Canes Venatici cloud in the Virgo Supercluster.
The two most massive members of the group are the Milky Way and the Andromeda Galaxy. These two barred spirals each have a system of satellite galaxies.
The Milky Way's satellite system consists of Sag DEG, Large Magellanic Cloud, Small Magellanic Cloud, Canis Major Dwarf, Ursa Minor Dwarf, Draco Dwarf, Carina Dwarf, Sextans Dwarf, Sculptor Dwarf, Fornax Dwarf, Leo I, Leo II and Ursa Major Dwarf.
Andromeda's system comprises M32, M110, NGC 147, NGC 185, And I, And II, And III, And IV, And V, Pegasus dSph, Cassiopeia Dwarf, And VIII, And IX, and And X.
M33 (Triangulum), the third largest, and only ordinary spiral galaxy in the Local Group, may or may not be a companion to the Andromeda galaxy but probably has Pisces Dwarf as a satellite.
There are other members of the group which are gravitationally secluded from these large subgroups.
Confining our attention to the 13 satellite galaxies of the Milky Way, we discover the nearest two are:
SAGITTARIUS DWARF ELLIPTICAL GALAXY; The Sagittarius Dwarf Elliptical Galaxy (SagDEG) is an elliptically looped shaped satellite galaxy of the Milky Way Galaxy. The main cluster which was first to be discovered in 1994 is roughly 10,000 light years in diameter, and is currently about 70,000 light years from Earth and traveling in a polar orbit at a distance of about 50,000 light years from the core of the Milky Way (about 1/3 the distance of the Large Magellanic Cloud).
Although it is one of the closest companion galaxies to the Milky Way, the main parent cluster is on the opposite side of the galactic core from Earth, and consequently is very faint, although it covers a large area of the sky.
Officially discovered in 1994, by Rodrigo Ibata, Mike Irwin, and Gerry Gilmore, Sag DEG was immediately recognized as being the nearest known neighbour to our Milky Way at the time.
From its discovery until 2003, it was considered to be the closest outside galaxy to Earth, but since then has been overtaken by the newly discovered Canis Major Dwarf Galaxy.
CANIS MAJOR DWARF GALAXY: The Canis Major dwarf galaxy is classified as an irregular galaxy and is now thought to be the closest neighbouring galaxy to our location in the Milky Way, being located about 25,000 light-years away from our Solar System and 42,000 light-years from the Galactic Center. It has a roughly elliptical shape and is thought to contain as many stars (1 billion) as the Sagittarius Dwarf Elliptical Galaxy, the previous contender for closest galaxy to our location in the Milky Way.
The galaxy was first discovered in November 2003 by an international team of French, Italian, British and Australian astronomers. Although closer to the Earth than the centre of the galaxy itself, the Canis Major Dwarf galaxy was difficult to detect as it is located behind the plane of the Milky Way, where concentrations of stars, gas and dust are densest. This, along with its small size, explains why it was not discovered sooner.
TO SUM UP:
M31 is 2,52 million light years away,
M33 is 2,59 million light years away,
Sagittarius Dwarf Elliptical Galaxy is 70,000 light years away
The Canis Major dwarf galaxy is 25,000 light years away
OTHER SATELLITE GALAXIES:
(in order of distance away)
The Large Magellanic Cloud is at a distance of 168,000 light years). It has about 1/20 the diameter of our galaxy and 1/10 the number of stars (i.e. about 10^10 stars).
The Small Magellanic Cloud contains around a billion stars and is at a distance of about 200,000 light-years, It is also one of the most distant objects that can be seen with the naked eye.
Both were first observed by the Portuguese mariner Ferdinand Magellan (1480–1521) in his attempted circumnavigation of the world,
The Ursa Minor Dwarf elliptical galaxy, discovered in 1954. is at a distance of 240,000 light years away,
The Sculptor Dwarf Galaxy, discovered in 1938 is a dwarf spheroidal galaxy and lies 254,000 light years from the solar system.
The Draco Dwarf galaxy was discovered in 1954 and is at a distance of 280,000 light years away,
The Sextans Dwarf galaxy, discovered in 1990, is an elliptical galaxy, receding from the Milky Way at 238 km/s and is at a distance of 320,000 light years away,
Ursa Major Dwarf Galaxy, discovered in 2005, is a dwarf spheroidal galaxy measuring only a few thousand light years in diameter and is the second least luminous galaxy known and is located at a distance of about 330,000 light years from the Earth.
The Carina Dwarf galaxy, discovered in 1977 with the UK Schmidt Telescope, is receding from the Milky Way at 229 km/s and is at a distance of 360,000 light years away,
The Fornax Dwarf was discovered in 1938, is receding from the Milky Way at 53 km/s and is at a distance of 460,000 light years away,
Leo II (or Leo B), discovered in 1950, is a dwarf spheroidal galaxy approximately 701,000 light years from Earth, and 4,200 light-years in diameter.
Leo I is a dwarf spheroidal galaxy discovered in 1950 and is at a distance of 815,000 ± 82,000 light years away,
2006-09-20 12:50:47 · answer #1 · answered by Anonymous · 12⤊ 0⤋
We are inside the Milky Way, which is a pretty big galaxy.
The Milky Way has two companion galaxies for sure, the Large and Small Magellanic Clouds. There may be others.
Then there are the galaxies in the local group. M31, the Andromeda Galaxy, is the biggest galaxy in the Local Group, but it is not the closest to us---several other, smaller group members are closer.
2006-09-20 08:32:02 · answer #2 · answered by cosmo 7 · 1⤊ 0⤋
Tue, 04 Nov 2003 - An international team of astronomers have discovered a new galaxy colliding with our own Milky Way. This new galaxy, Canis Major, is located only 42,000 light years away from the centre of the Milky Way - it's our new "closest galaxy".
2006-09-21 09:37:37 · answer #3 · answered by Anonymous · 0⤊ 0⤋
There are many small dwarf galaxies that are satellites of our Milky Way Galaxy (or are being absorbed by it). The nearest large galaxy is the Andromeda galaxy, (or M31). It's visible as a faint oval patch to the naked eye if you know where to look, and is easy to see in binoculars. It's about 2.9 million light years away.
2006-09-20 09:35:15 · answer #4 · answered by Zhimbo 4 · 1⤊ 0⤋
The galaxy that is closest to us is the one we live in. The Milky Way galaxy.
2006-09-20 09:13:58 · answer #5 · answered by Tim C 4 · 0⤊ 0⤋
Andromeda
2006-09-21 03:30:20 · answer #6 · answered by Anonymous · 0⤊ 0⤋
I think we still have a little time. Maybe next week we should look into it though. Liberal AssKicker, Do you have any clue about science at all? Or do you just troll around saying the total opposite of what the person asking is looking for just to annoy people? I"m curious. also, why do you never actually debate anyone one here?
2016-03-26 23:16:48 · answer #7 · answered by Anonymous · 0⤊ 0⤋
The perfect answer is only "Andromeda".It is said to be coming closer to milky way & around 1.5 billion(the fig may be incorrect or app) in future it will collide with milky way.
2006-09-21 03:58:16 · answer #8 · answered by ADITYA S 2 · 0⤊ 0⤋
andromeda is the nearest galaxy to ours and it is visible in the night sky as a star.
2006-09-21 06:32:22 · answer #9 · answered by § mǎddy § 2 · 0⤊ 0⤋
Andromeda galaxy.i am sure aliens are there in a solar system of Andromeda galaxy.
2006-09-20 19:22:04 · answer #10 · answered by Anonymous · 0⤊ 0⤋
The Universe
2006-09-20 08:10:46 · answer #11 · answered by BLoNdE22 1 · 0⤊ 5⤋