Although they look far apart, M31 and M33 are locked in a mutual gravitational embrace. Radio astronomers have found indications of a bridge of neutral hydrogen gas that could connect the two, evidence of a closer encounter in the past. Based on measurements, gravitational simulations currently predict that the Milky Way, M31, and M33 will all undergo mutual close encounters and potentially mergers, billions of years in the future.
What's happening at the center of spiral galaxy M106? A swirling disk of stars and gas, M106's appearance is dominated by blue spiral arms and red dust lanes near the nucleus, as shown in the featured image. The core of M106 glows brightly in radio waves and X-rays where twin jets have been found running the length of the galaxy. An unusual central glow makesM106 one of the closest examples of the Seyfert class of galaxies, where vast amounts of glowing gas are thought to be falling into a central massive black hole. M106, also designated NGC4258, is a relatively close 23.5 million light years away, spans 60 thousand light years across, and can be seen with a small telescope towards the constellation of the Hunting Dogs (Canes Venatici).
Five billion light-years from earth, there's a massive galactic pileup unfolding in slow motion. As four clusters of galaxies plow into each other, thousands of individual galaxies are colliding—creating huge amounts of cosmic chaos and a lot of energy.
New images of this phenomenon—one of the largest galactic mergers on record—suggest it's also producing more than just pretty pictures. It's also serving as quite possibly the largest particle accelerator of all time, besting the exquisitely engineered Large Hadron Collider one million times over.
The galaxy has a diameter of around 100,000 light years, making it about the size of the Milky Way. Notably, six observed supernovae exist within Messier 61, placing it in a group of galaxies which includes Messier 83, also with six supernovae observed, and NGC 6946, having nine observed supernovae. Messier 61 makes up part of the Virgo Galaxy Cluster, a massive group of galaxies in the constellation of Virgo (the Virgin).