How many galaxies do you see here? When NGC 6052 was discovered in the late 1700s, it was classified as an irregular galaxy because of its unusual shape. The Hubble Space Telescope image here gives us a clearer picture of what is happening. NGC 6052 is actually two spiral galaxies in the process of crashing into each other.
NGC 6052 gives us a preview of our future. In about 4 billion years, our galaxy, the Milky Way, will collide with our neighbor Andromeda.
Haro 11 is a "starburst" galaxy that is producing new stars at a rate that is 20 times higher than in our own Milky Way galaxy. The many massive newborn stars give Haro 11 its bluish color. Astronomers believe that Haro 11 formed when two smaller galaxies merged.
What kind of a name is SDSS J143450.62+033842.5? There are so many galaxies in the cosmos that it is difficult to name them all. Most distant galaxies are named by their right ascension and declination, coordinates for finding astronomical objects in the sky (similar to longitude and latitude on Earth). The letters indicate that it was identified by the Sloan Digital Sky Survey (SDSS).
Most galaxies in the cosmos are moving apart from each other. However, if galaxies are close enough to each other (like the two galaxies in UGC 2369), gravity can pull them together, causing them to collide and eventually merge.
J095000+731408 is another distant galaxy that is named for its position in the sky. It is part of a small group of nine galaxies associated with a bright radio source, 4C 73.08, which likely harbors a supermassive black hole. You can see the other galaxies in this group by panning around this image taken with the Hubble Space Telescope.
This galaxy is one of the closest in a region of sky known as the "GOODS North" field. The Great Observatories Origins Deep Survey (GOODS) included detailed observations of two regions of sky (one northern and one southern) by NASA's Hubble, Spitzer, and Chandra Telescopes and the European Space Agency's Herschel and XMM-Newton Telescopes. This image shows the GOODS North field as observed by the Hubble Space Telescope.
After you have estimated the distance to the nearby galaxy, pan around the image to see other galaxies that are much farther away. Astronomers have measured distances to almost 3,000 galaxies in this region. How many of them can you spot in the image?
Hercules A is a very large elliptical galaxy with a mass that is roughly 1,000 times that of our Milky Way galaxy. This image combines observations from the Hubble Space Telescope and the Jansky Very Large Array radio telescope. The radio observations (shown in pink in false color) show enormous jets that are powered by a supermassive black hole at the center of the galaxy. The jets consist of high-energy plasma that has been blasted almost a million light-years away from the galaxy center, directed by magnetic fields.
Abell 370 is a galaxy cluster and contains several hundred galaxies bound together by gravity. All types of galaxies are represented in this cluster, including spirals and ellipticals and the small blue irregular galaxy whose distance you will estimate.
Note that there are also several long arcs that appear streaked between the galaxies. These are images of far more distant galaxies behind the cluster that have been magnified and distorted by the immense mass of the cluster in a phenomenon known as gravitational lensing.