Panorama of Nearest Galaxy Unveils Hundreds of Millions of Stars
On a chilly, crystal-clear autumn night you can see the farthest object visible in the universe without the aid of a telescope or binoculars. Just to the northeast of the Great Square of Pegasus, it appears as a spindle-shaped patch of haze with a bright center. It is the nearest galaxy to our Milky Way, the magnificent Andromeda galaxy. The faint light you are seeing left the spiral galaxy 2.5 million years ago to cross the immense gulf in intergalactic space toward Earth. Back then, on Earth, one of the earliest known humans, Homo habilis, appeared. This early ancestor has been nicknamed "handy man," as the maker of the first stone tools.
Fast forward to early decade of the 21st century, when one of the most powerful science tools ever conceived by humans – the Hubble Space Telescope – took over 10 years to make a photomosaic portrait of the galaxy's ancient light, taking over 600 snapshots. Why such a monumental task? The galaxy is so close to us, that in angular size it is six times the apparent diameter of the full Moon. For Hubble's pinpoint view, that's a lot of celestial real estate to cover. This stunning, colorful mosaic, captures the glow of 200 million stars. That's still a fraction of Andromeda's population. And the stars-dotted images are crammed into at least 2.5 billion pixels. Try framing that portrait! Hubble's detailed look at the resolved stars will help astronomers piece together the galaxy's past history that includes mergers with smaller satellite galaxies.
Find additional articles, images, and videos at HubbleSite.org
You are receiving this email because you are subscribed to the Inbox Astronomy mailing list.
No comments:
Post a Comment