Image Credit: NASA, ESA and the Hubble SM4 ERO Team
Yes, I know I'm a whole 6 hours late to the game in bringing you these photos, during which time every other science-related blog in the world already posted them. But they are just so cool, I'm going to post them anyway.
Last May, the space shuttle Atlantis visited the Hubble Space Telescope for their fifth and final servicing mission. Hubble has certainly been one of the crowning achievements of NASA and the Space Shuttle program; the astronauts transformed a dud of a telescope into one of the most important astrophysical laboratories ever built. In May, astronauts replaced two instruments and repaired two others, plus gave Hubble new batteries, gyroscopes and some other minor repairs. Today, after nearly five months of sometimes frustrating checkout and calibration, NASA released its first images from the repaired Hubble.
You can look at all of today's images here. There are pictures of the colorful center of the Milky Way Galaxy's biggest globular cluster, omega Centauri. That picture shows the power of Hubble. From the ground, the center of omega Centauri looks like a blob of starlight, there are so many stars! Yet Hubble resolves them all. The Hubble also imaged the birth of a new star and the death of an old one.
For those of you who can speak spectra (the splitting of light into its component colors), there are some amazing spectra from the uber-massive star eta Carinae (a star nearly 100 times the mass of the sun, about as big as any single star can get!), spectra of gas near a supermassive black hole showing changes over the past 10 years, and more. While spectra are often less inspiring for the general public to look at, they carry far more information than you might guess. From a spectrum, we can determine the speed of a moving object, its atomic composition, its temperature, its atmospheric pressure, and other important quantities that a picture alone could never tell.
My favorite image (and the one at the top of this article) is of Stephan's Quintet, a tight grouping of five galaxies. Four of the galaxies (the yellowish ones) are located 290 million light years away and are so close together, gravity is ripping off pieces of the galaxies, creating streams of stars and rings of new star formation. The fifth galaxy, the whiter one in the upper left of this image, is not related to the others. It is only 40 million light years away, and just happens to be along the line of sight to the other galaxies. Just think -- when the light that Hubble saw left the more distant quartet of galaxies, the first dinosaurs were just starting to roam the Earth. When that light passed the closest galaxy, dinosaurs had already been dead for 25 million years, and the earliest humans were still 38 million years away. But the neatest part of this image is the zoomable version, so you can zoom in and around the image to see amazing details. You can see individual stars in the closest galaxy! Cool stuff.
Anyway, Hubble is now doing hard core science again (and has been for a few weeks). Thanks once again to the amazing team of astronauts and ground crew for fixing this marvelous telescope!
Note: At times I've been getting some errors when trying to access views of some images. If this happens to you, take a deep breath and try again. They must be popular!