Messier 77 is a galaxy in the constellation of Cetus, some 45 million light-years away from us. Also known as NGC 1068, it is one of the most famous and well-studied galaxies. It is a real star among galaxies, with more papers written about it than many other galaxies put together!
Despite its current fame and striking swirling appearance, the galaxy has been a victim of mistaken identity a couple of times; when it was initially discovered in 1780, the distinction between gas clouds and galaxies was not known, causing finder Pierre Mechain to miss its true nature and label it as a nebula. It was misclassified again when it was subsequently listed in the Messier Catalogue as a star cluster.
Now, however, it is firmly categorised as a barred spiral galaxy, with loosely wound arms and a relatively small central bulge. It is the closest and brightest example of a particular class of galaxies known as Seyfert galaxies -- galaxies that are full of hot, highly ionised gas that glows brightly, emitting intense radiation.
Strong radiation like this is known to come from the heart of Messier 77 -- caused by a very active black hole that is around 15 million times the mass of our Sun. Material is dragged towards this black hole and circles around it, heating up and glowing strongly. This region of a galaxy alone, although comparatively small, can be tens of thousands of times brighter than a typical galaxy.
Although no competition for the intense centre, Messier 77's spiral arms are also very bright regions. Dotted along each arm are knotty red clumps -- a signal that new stars are forming. These baby stars shine strongly, ionising nearby gas which then glows a deep red colour as seen in the image above. The dust lanes stretching across this image appear as a rusty, brown-red colour due to a phenomenon known as reddening; the dust absorbs more blue light than red light, enhancing its apparent redness.
ESA/Hubble Information Centre: http://www.spacetelescope.org
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
The U.S. intelligence community has thrown its support behind a bid by commercial space imagery provider DigitalGlobe Inc to sell higher resolution images from its satellites, the leading U.S. intelligence official said Tuesday.
Russians with smartphones and dashboard cameras captured footage of a meteor that flashed across the night sky near the Arctic Circle over the weekend.
NASA and Google will send floating robots equipped with 3-D mapping technology into orbit this summer, enabling them to navigate autonomously for the first time. "The future is awesome," brags Google
Kepler-186f is almost the same size as Earth, and it orbits in its star's "Goldilocks zone"-- where temperatures may be just right for life. But much is unknown because it's also 500 light-years away.
Scientists say they have discovered what could be the birth of a new moon in the rings of Saturn.
A crucible of bright stars illuminates a nebula in glowing red hydrogen that would normally be too faint for the human eye to see
As part of its next cargo delivery run, commercial spaceflight's darling will try out rocket legs that may help lower spacecraft costs by a factor of 100
A NASA mission to pluck samples from a distant asteroid and return them to Earth passed a major technical review, clearing engineers to begin building the robotic spacecraft, officials said on Thursday.
Aerospace giant Boeing is designing a new type of aircraft capable of taking off, hovering and landing vertically
Photos snapped by the Mars rover Curiosity appear to show strange lights.