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.
With a temperature of 250,000 °C — 45 times that at the surface of our Sun — astronomers believe that this dying star in the outskirts of the Milky Way may have peaked at 400,000 °C a thousand years ago. The researchers were also the first to observe an intergalactic gas cloud moving towards the Milky Way — indicating that galaxies collect fresh material from deep space, which they can use to make new stars.
Astronomers are using the Hubble Space Telescope to study massive stars in a stellar nursery near the Tarantula Nebula to learn why most form in clusters but some appear to form in isolation.
This NASA/ESA Hubble Space Telescope image reveals the vibrant core of the galaxy NGC 3125, approximately 50 million light-years away. Discovered by John Herschel in 1835, NGC 3125 is a great example of a starburst galaxy — a galaxy in which unusually high numbers of new stars are forming, springing to life within intensely hot clouds of gas.
