Face-on starburst spiral galaxy MCG+07-33-027 lies 300 million light-years from Earth in the constellation of Hercules. Click the image for a full-size version. Image credit: ESA/Hubble & NASA and N. Grogin (STScI).This image was taken by the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys (ACS), and shows a starburst galaxy named MCG+07-33-027. This galaxy lies some 300 million light-years away from us, and is currently experiencing an extraordinarily high rate of star formation — a starburst. Normal galaxies produce only a couple of new stars per year, but starburst galaxies can produce a hundred times more than that! As MCG+07-33-027 is seen face-on, the galaxy’s spiral arms and the bright star-forming regions within them are clearly visible and easy for astronomers to study.
In order to form newborn stars, the parent galaxy has to hold a large reservoir of gas, which is slowly depleted to spawn stars over time. For galaxies in a state of starburst, this intense period of star formation has to be triggered somehow — often this happens due to a collision with another galaxy. MCG+07-33-027, however, is special; while many galaxies are located within a large cluster of galaxies, MCG+07-33-027 is a field galaxy, which means it is rather isolated. Thus, the triggering of the starburst was most likely not due to a collision with a neighbouring or passing galaxy and astronomers are still speculating about the cause.
Elliptical galaxy NGC 3610 is the most prominent object in this amazing Hubble image — and a very interesting one at that! Discovered in 1793 by William Herschel, it was later found that this galaxy contains a disc. This is very unusual, as discs are one of the main distinguishing features of a spiral galaxy. And the disc in NGC 3610 is remarkably bright.
Astronomers using the NASA/ESA Hubble Space Telescope have conducted the first search for atmospheres around temperate, Earth-sized planets beyond our solar system. They found indications that increase the chances of habitability on two exoplanets known as TRAPPIST-1b and TRAPPIST-1c orbiting a red dwarf star approximately 40 light-years away.
Galactic arms, sunflowers and whirlpools are only a few examples of nature’s apparent preference for spirals. A beautiful example is Messier 63, nicknamed the Sunflower Galaxy, its winding arms shining bright due to the presence of recently formed, blue–white giant stars and clusters, readily seen in this NASA/ESA Hubble Space Telescope image.
