Messier 31 (M31)

Common Name: Andromeda Galaxy

Also Known as: NGC 224, Bode 3, Flamsteed 58

Object Type: Spiral Galaxy

Constellation: Andromeda

Distance from Earth: 2.54 million light years

Apparent Magnitude: 3.44

Coordinates: RA 00H 42M 44.3S DEC 41 deg 16 min 9 sec

Actual Size: 152,000 light years in diameter

Apparent Dimensions: 3.167 degrees x 1 degree

Discovered by: The earliest record of M31 comes from the Persian astronomer Abd al-Rahman al-Sufi, who mentioned the chained constellation, referring to Andromeda, or the Chained Maiden, in his Book of Fixed Stars in 964.
Al-Sufi described the Andromeda Galaxy as a “small cloud.” The first documented telescopic observation of the galaxy was provided by the German astronomer Simon Marius on December 15, 1612. In 1917 Heber Curtis saw a nova in M31 and was a proponent of the idea that M31 was, in fact, a galaxy.
The true nature of M31 wasn’t proven until 1923 when Edwin Hubble established the intergalactic distance to M31.

Description: The Andromeda Galaxy was named after the area of the sky that it occupies, the constellation Andromeda, which represents the princess Andromeda in Greek mythology.
Andromeda was chained to a rock and left to a sea monster to appease Poseidon after her mother Cassiopeia had boasted that her daughter’s beauty surpassed that of the sea nymphs. The princess was saved by Perseus, the Greek hero represented by the neighbouring constellation.
Messier 31 is the largest and most massive member of the Local Group of galaxies, which also includes the Milky Way, the Triangulum Galaxy (M33) and more than 40 smaller galaxies.
The Andromeda Galaxy has a total of 14 satellite galaxies, of which Messier 32 and Messier 110 are the largest and easiest to observe.
M32 is believed to have undergone a close encounter with M31, which resulted in the smaller galaxy losing its stellar disk and undergoing a dramatic increase in star forming activity in the central region.
The starburst activity in M31 ended in the relatively recent past.
The Andromeda Galaxy contains a trillion stars, more than twice as many as the Milky Way, which is home to 200 to 400 billion stars.
Messier 31 is approaching the Milky Way at about 110 km/s. It is one of the few blueshifted galaxies (moving toward us) from our point of view.
Andromeda is expected to directly collide with our galaxy in about 4 billion years. The collision will most likely result in a merger of the two large galaxies into a giant elliptical galaxy, and possibly even a large disk galaxy.
Before the galaxies merge, our solar system may be ejected from the Milky Way and join Andromeda.

Click Below Image(s) for Full Size:

The Andromeda Galaxy is relatively easy to find in the sky as it is one of the brightest Messier objects. It lies in the vicinity of two prominent asterisms in the northern sky: the Great Square of Pegasus (formed by Alpheratz, Algenib, Markab and Scheat) and Cassiopeia’s W. The only objects listed in Messier’s catalogue that are brighter than M31 are the Pleiades (M45) and the Ptolemy Cluster (M7). It is one of the most distant deep sky objects visible to the un-aided eye. In 10 x 50 binoculars the galaxy appears as an oval shaped cloud with a bright nucleus. It is so large that it is 6 times larger than the diameter of the full Moon. In 10×50 binoculars, the galaxy appears as an oval shaped cloud with a bright nucleus. Binoculars and small telescopes reveal only the galaxy’s bright core, but larger instruments show its full size. The Andromeda Galaxy’s brightest companions, the dwarf galaxies Messier 32 and Messier 110, can also be seen in binoculars.

The best time to view M31 is October-December.

Platesolve

M31 Andromeda Galaxy

Imaging Details
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