Just in time for the holidays, the folks at the Space Telescope Science Institute in Baltimore, Maryland, give us a glimpse of a heavenly angel - not literally one of the seraphim, of course, but an astronomical delight nonetheless. The two-lobed star-forming region, dubbed Sharpless 2-106, is located in an isolated part of our Milky Way galaxy nearly 2000 light-years from Earth. The bluish "wings" are lobes of super-hot gas illuminated by a monster star - dozens of times the mass of our sun - forming in the center of the still-expanding nebula. A dark ring of dust and gas circling the star (dark bands, center), material that may one day coalesce into a planetary system, acts like a belt, cinching the nebula into an hourglass shape. Observations of the nebula at purely infrared wavelengths reveal more than 600 brown dwarfs, so-called "failed stars" that each gives off more heat than it receives but lacks enough mass to ignite and produce nuclear fusion on its own.

Happy Holidays!

How often do stars eat their young? Almost never, according to a paper submitted to The Astrophysical Journal. While planets typically migrate inward due to the torque (or gravitational push) of the pancake-like proto-planetary disks of dust and gas in which they form (seen in this picture), what hasn't been clear until now is what causes them to stop. In the new study, researchers ran computer simulations on 126 confirmed extrasolar planets detected by ground observatories and 649 candidate extrasolar planets detected by NASA's Kepler spacecraft. Their results indicate that planetary migration is actually stopped by a gap that is created by the star's accretion of material from the disk. There, the disk's torque driving the planet's inward migration disappears and the planet stabilizes in roughly a 4-day orbit (about 10 times the radius of a solar-type star). Based on their findings, the scientists conclude that cannibalized planets are extremely rare.

Scientists analyzing decades-old images with new eyes are seeing signs that Jupiter's radiation-blasted moon Europa may harbor giant under-ice "lakes" that could sustain life. Europa doesn't lack for the prime ingredient for life: liquid water. The moon has a global ocean hundreds of kilometers deep that is covered by a layer of ice perhaps 10 or 20 kilometers thick. But a team of glaciologists and planetary scientists report online today in Nature that - judging by the way erupting volcanoes on Earth disrupt their ice caps - huge pools of water must lie as little as 3 kilometers beneath the surface. On Europa, rather than a volcano, a rising plume of warmer but still solid ice would drive ice melting a few kilometers beneath the surface. And then a briny slush of ice would rise from the resulting lake and disrupt the surface to form Europa's long-known chaotic terrains of jumbled ice blocks. Direct confirmation of giant Europan lakes each holding the combined volume of North America's Great Lakes must await radar probing by a multibillion-dollar spacecraft that is still stuck on planetary scientists' wish list.

The great Andromeda Galaxy owes a bit of its beauty to a dalliance with another galaxy billions of years ago, according to new data gathered with NASA's orbiting Hubble Space Telescope. Lying 2.5 million light-years from Earth, the Andromeda Galaxy is the closest giant spiral to our own and the largest member of the Local Group, the collection of several dozen nearby galaxies that includes our Milky Way, which ranks number second largest. The new observations reveal that Andromeda - shown here in infrared (yellow and orange) and x-rays (blue and white) - experienced a rash of star formation in its outermost disk 1.5 to 3 billion years ago, as reported in a paper in press at Monthly Notices of the Royal Astronomical Society. The likely trigger? Spiral galaxy M33 - the Local Group's third largest galaxy, 2.8 million light-years from us?which swung by Andromeda at the time and experienced its own starburst, suggesting each galaxy's gravity caused gas in the other to collapse and create new stars.

More Brainless Tales