Skip to main content

Hubble captures a formation of galaxies neatly lined up

Sometimes, Hubble or other telescopes will capture two or more galaxies that are in the process of merging — called interacting galaxies. These huge collisions can warp one or both of the galaxies, twisting them into strange shapes. The results of such collisions can be catastrophic, with one of the galaxies being destroyed. Or they can be creative, with one larger galaxy being formed from the two merging galaxies.

However, sometimes galaxies that appear very close in images are not actually interacting. Sometimes, they merely appear to be close when seen from Earth, but they can actually be thousands of light-years apart. That’s the case with a previous Hubble image showing two overlapping galaxies.

The latest Hubble image shows an interesting mix, which is a twist on this premise: it features both an interacting galaxy system and a string of galaxies that happen to line up in a neat procession.

An interacting galaxy system known as Arp-Madore 2105-332, that lies about 200 million light-years from Earth in the constellation Microscopium.
This image features an interacting galaxy system known as Arp-Madore 2105-332, that lies about 200 million light-years from Earth in the constellation Microscopium. Like other recent Hubble Pictures of the Week, this system belongs to the Arp-Madore catalog of peculiar galaxies. The wonderful quality of this image also reveals several further galaxies, not associated with this system but fortuitously positioned in such a way that they appear to be forming a line that approaches the leftmost (in this image) component of Arp-Madore 2105-332, which is known individually as 2MASX J21080752-3314337. The rightmost galaxy, meanwhile, is known as 2MASX J21080362-3313196. These hefty names do not lend themselves to easy memorization, but they do actually contain valuable information: They are coordinates in the right ascension and declination system used widely by astronomers to locate astronomical objects. ESA/Hubble & NASA, J. Dalcanton; CC BY 4.0 Acknowledgement: L. Shatz

The interacting galaxies are called Arp-Madore 2105-332 and are located 200 million light-years away. Even though the two look fairly far apart in this image, with one in the middle and one to the right of the frame, they are close enough in galactic terms to be affecting each other gravitationally. Beneath the leftmost part of the galaxy pair is a string of other galaxies lined up purely by coincidence.

The interacting galaxies are named Arp-Madore because of the catalog they are named in, which collects together unusual galaxies known as peculiar galaxies. Among these peculiar galaxies are those that have been pulled into unusual shapes due to mergers or are in the process of interacting. Peculiar galaxies can have one spiral arm brighter than the others, or two supermassive black holes at their center, or be affected by a nearby satellite galaxy, or even be a stunning ring shape.

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
Hubble gets festive with a string of cosmic Christmas lights
The billion stars in galaxy UGC 8091 resemble a sparkling snow globe in this festive Hubble Space Telescope image from NASA and ESA (European Space Agency). The dwarf galaxy is approximately 7 million light-years from Earth in the constellation Virgo. It is considered an "irregular galaxy" because it does not have an orderly spiral or elliptical appearance. Instead, the stars that make up this celestial gathering look more like a brightly shining tangle of string lights than a galaxy.

Researchers using the Hubble Space Telescope are getting into the festive spirit with a holiday image showing a dwarf irregular galaxy called UGC 8091. Located 7 million light-years away in the constellation of Virgo, this region is a hotbed of star formation, with bright young stars illuminating the gas around them to create a sparkling mass reminiscent of Christmas lights.

It is designated an irregular galaxy because of its nonuniform shape, and a dwarf galaxy because of its small size. Unlike spiral galaxies, such as our Milky Way, or elliptical galaxies, which are smooth and have a elliptical shape, irregular galaxies can come in a variety of shapes. Often, these galaxies have been pulled into odd shapes due to gravitational forces, such as when two galaxies come close to each other and interact.

Read more
Scientists investigate star formation in the famous Whirlpool Galaxy
This illustration depicts the distribution of diazenylium molecule radiation (false colours) in the Whirlpool Galaxy, compared with an optical image. The reddish areas in the photograph represent luminous gas nebulae containing hot, massive stars traversing dark zones of gas and dust in the spiral arms. The presence of diazenylium in these dark regions suggests particularly cold and dense gas clouds.

Scientists are turning to the beautiful and famous Whirlpool Galaxy to look for areas where stars could eventually be born. By mapping out the presence of particular chemicals, they hope to learn about the conditions that are required to give birth to new stars.

Researchers have mapped out regions of cold gas within the Whirlpool Galaxy, as it is these pockets of gas that gradually condense to form the knots that are the seeds of new stars. These knots attract more dust and gas due to gravity until they eventually become dense enough to collapse into a hot core called a protostar.

Read more
Hubble Space Telescope is back up and running following gyro problem
Hubble orbiting more than 300 miles above Earth as seen from the space shuttle.

The Hubble Space Telescope is back to full operations after spending several weeks in safe mode due to a problem with one of its components. The telescope first experienced issues with one of its gyros on November 19, and was in and out of safe mode several times in the following days. It has remained in safe mode since November 23, but came back online on Friday, December 8.

The problem was caused by one of the telescope's three operational gyros, which are devices that help to point the telescope in the right direction. Although it would have been possible to operate the telescope with just one of these, that would have resulted in lost observing time as it would take longer to move the telescope to a new target between observations. With all three gyros now back in use, the telescope has returned to science operations.

Read more