Looking Up: Galactic Hydra-tion

Apr 9, 2018

Two stars within our own Milky Way galaxy anchor the foreground of this cosmic snapshot. Beyond them lie the galaxies of the Hydra Cluster.
Credit Angus Lau / nasa.gov

As it turns out, galaxies tend to hang out in groups. We learn more about that on this week's Looking Up.

April showers bring May flowers, but clear nights in April bring one of the most wonderful and beautiful things up in the sky, clusters of galaxies.

You’ll recall that galaxies are giant, massive, huge collections of stars. Our own Milky Way has roughly 200 – 300 BILLION stars. And that’s not even that big. Our neighbor galaxy, Andromeda, has upwards of a trillion stars.

Galaxies are often found in groups, bound by gravity. Our own group is called the Local Group, with Andromeda as the biggest, the Milky Way second, and roughly 50 smaller galaxies gravitationally bound to each other.

Up in the Colorado sky right now is the Hydra Cluster of galaxies, in the constellation, can you guess? Hydra! This wonderful cluster contains upwards of 100 galaxies, about 165 million light years away. You’ll need a dark sky and a telescope to see some of those fuzzy patches of light that represent billions of stars, so come to one of our star parties, and check out this great group of galaxies.

If you’d like to take a closer look at the Hydra Galaxy Cluster or any of the other wonderful and amazing things in the sky, please visit csastro.org for a link to information on our monthly meetings and our free public star parties.