The Antennae Galaxies are two galaxies, NGC 4039 and NGC 4038, currently colliding with each other, located roughly 43 million light years from the Milky Way.
It is believed that NGC 4039 and NGC 4038 started colliding 1.2 billion years ago, and it was believed that NGC 4038 was a barred spiral galaxy and NGC 4039 was a spiral galaxy.
The two galaxies are believed to be in collision for less than a billion years. They are named "Antennae" because of a long trail of gas and dust that spirals away from the merging galaxies.
Although discovered by William Herschel in 1785, when Humanity had begun cataloging astronomical features, the Confederacy of Humanity had first explored the galaxies in 10450. To their surprisement, the galaxy was almost devoid of galactic civilisations until they discovered the Mensar in 10457, a few years later.
Since 9970, the Mensar have become a galactic civilisation spanning both galaxies. In their culture, the two galaxies are a symbol for hope and change within their civilisation. Only on a few colony worlds the Mensar have constructed temples, most of which were built in the 7500s and have eroded since then.
When the Confederacy attempted to make contact with the Mensar, the signals were ignored and the Mensar deployed a galactic defence system in case of a sudden invasion. The Mensar and Humanity remain seperate from each other.