Information on some Nearby Galaxy Groups

Sculptor Group☯️

The Sculptor group is the nearest group of galaxies to the Local Group and is dominated by five galaxies, four spiral - NGC 247, 253, 300 and 7793 and one irregular - NGC 55. The nearest of these is NGC 55 which lies on the border of the Sculptor group and our Local group.

Maffei Group☯️

In 1968, the Italian astronomer Paolo Maffei discovered two galaxies hidden behind the plane of our galaxy and thus heavily obscured by interstellar matter. These two galaxies are known as Maffei 1 and Maffei 2. Together with the galaxy IC342, and the extremely obscured galaxy Dwingeloo 1 they make up the dominant members of another nearby group. Maffei 1 is the nearest large elliptical galaxy to us. Although observation of the group is difficult, there are now over 20 member galaxies known, most of which are dwarfs.

M81 Group☯️

This is a prominent nearby group in Ursa Major and is centred around the famous M81/M82 pair of galaxies together with the fairly bright NGC 2403 galaxy. M82 is a famous starburst galaxy, the galaxy has had a close encounter with its larger neighbour M81 in the past few million years, and the near-miss has generated a large wave of star formation within the galaxy.

Canes I Group☯️

Another nearby group centred around NGC 4214, 4244 and 4395. The spiral galaxy M94 also probably lies at the back of this group. This group is notable for containing a large number of medium-sized dwarf galaxies.

NGC 5128 Group☯️

This is a neighbouring group of galaxies in Centaurus and is dominated by the two spiral galaxies M83 and NGC 4945 and the large lenticular galaxy NGC 5128. NGC 5128 is one of the brightest nearby galaxies and it is a powerful source of radio waves (radio astronomers call the galaxy Centaurus A). The galaxy also seems to have merged with a large spiral galaxy within the past few hundred million years.

M101 Group☯️

This group is centred around the famous M101 galaxy which is one of the nearest giant spiral galaxies - it has a diameter of 200 thousand light years. Near this group lies the M51 (NGC 5194) group, and these two groups are often included together in lists as one large group.

Canes II Group☯️

Another large collection of spiral galaxies in Canes Venatici, the dominant members are probably M106, NGC 4096 and NGC 4490, but there are many other galaxy groups in this area of the sky and this whole region is known as the Canes Cloud.

Leo I Group☯️

This is a large and prominant group of spiral galaxies in Leo consisting of two main subgroups, one centred around M65, M66 and NGC 3628, and the other centred around M95, M96, M105 and NGC 3384.

Virgo Cluster☯️

This is the most famous cluster of galaxies. It is much larger than any other group within 100 million light years. There are about 150 large galaxies in this cluster and at least a thousand known dwarf galaxies. This cluster completely dominates our tiny corner of the Universe, and even our Local Group of galaxies is being gravitationally pulled by this cluster. At the core of the Virgo cluster lie the three large elliptical galaxies M84, M86 and M87. These galaxies probably formed from the merger of many smaller galaxies and are much more massive than our own galaxy.

Ursa Major Groups☯️

This is a large spur of spiral galaxies on one side of the Virgo cluster stretching across 20 million light years of space. There are probably two main groups here - Ursa Major North (around NGC 3631, 3953, and M109) and Ursa Major South (around NGC 3726, 3938 and 4051).

Virgo II Groups☯️

The Virgo II groups are a long filament of galaxies extending southwards from the groups of galaxies at the southern edge of the Virgo cluster.

Fornax Cluster☯️

The second richest cluster within 100 million light years is the Fornax cluster although it is much smaller than the Virgo cluster. There are actually two neighbouring clusters here called the Fornax I cluster and the Fornax II or Eridanus group. These two clusters contain about 50 large galaxies each. The groups of galaxies around the Fornax cluster are sometimes called the Fornax supercluster or Southern supercluster.

Leo II Groups☯️

The Leo II Groups are a large collection of galaxy groups clustered about 30 million light years to one side of the Virgo cluster.

Virgo III Groups☯️

These galaxy groups stretching away from the Virgo cluster are called the Virgo III cloud. The gravitational pull of the Virgo cluster is probably why this collection of groups has been stretched into a long filament.

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