Mergers and Acquisitions


NGC6240NGC 6240 is a cosmic catastrophe in its final throes. It’s a titanic collision of galaxies throwing distorted tidal tails of stars, gas, and dust and undergoing massive bursts of star formation. The two supermassive black holes in the original galactic cores will also coalesce into a single, even more massive black hole. Eventually, only one large galaxy will remain.

Image Credit: NASA

A Lonely Dwarf


The Local Void is a vast, empty region of space adjacent to the Local Group, the group of galaxies that included our Milky Way. It’s composed of three separate sectors which are separated by bridges of “wispy filaments” of gas and dust. The exact size of the Local Void is unknown, but it is at least 150 million light-years across—and possibly 3 to 6 times larger still. It’s called a void because it has significantly fewer galaxies than expected from standard cosmology.

The irregular dwarf galaxy in the foreground of the picture is cataloged as KK 246, and it’s one of the few galaxies in the Local Void.

Image Credit: NASA / ESA

NGC 6814


A spiral snowflakeThis worth posting simply because it’s pretty.

NGC 6814 is an intermediate spiral galaxy in constellation Aquila located about 75 million light years from Earth. It’s a Seyfert galaxy with an extremely bright nucleus powered by a supermassive black hole with roughly 10 millions times the mass of the Sun. The galaxy is also a highly variable source of X-ray radiation. UV and optical emission also vary, although more smoothly, with time lag of two days behind the x-ray output.

Image Credit: ESA / NASA

Mergers and Acquisitions


Galaxy clusters are the largest objects in the universe held together by gravity. They can contain hundreds or thousands of galaxies held together in vast clouds of multi-million-degree gas glowing in X-rays.

The system known as Abell 2384 is the result of the collision of a pair galaxy cluster hundreds of millions of years ago. This composite image was put together using x-ray data from the Chandra X-ray Observatory and XMM-Newton (blue) and radio data from the Giant Metrewave Radio Telescope in India (red). It shows the superheated bridge of gas running through Abell 2384 and reveals the effects of a jet from a supermassive black hole in the center of a galaxy in one of the clusters. The jet is so powerful that it bends the shape of the 3 million light-year long gas bridge which has the mass of about 6 trillion Suns.

Image Credit: NASA