Highlights from Friday’s night launch (11:57 pm EDT!)
Archives for August 2009
Explanation: Pillars of gas, dust, and young, hot stars fill the center of NGC 7822. At the edge of a giant molecular cloud toward the northern constellation Cepheus, the glowing star forming region lies about 3,000 light-years away. Within the nebula, bright edges and tantalizing shapes are highlighted in this colorful skyscape. The image includes data from both broadband and narrowband filters, mapping emission from atomic oxygen, hydrogen, and sulfur into blue, green, and red hues. The atomic emission is powered by the energetic radiation from the hot stars, whose powerful winds and radiation also sculpt and erode the denser pillar shapes. Stars could still be forming inside the pillars by gravitational collapse, but as the pillars are eroded away, any forming stars will ultimately be cutoff from their reservoir of star stuff. This field spans around 30 light-years at the estimated distance of NGC 7822.
…and it’s at shirt.Woot this week!
Saturn has some weird moons. Check this bad boy out.
What has happened to Saturn’s moon Iapetus? Vast sections of this strange world are dark as coal, while others are as bright as ice. The composition of the dark material is unknown, but infrared spectra indicate that it possibly contains some dark form of carbon. Iapetus also has an unusual equatorial ridge that makes it appear like a walnut. To help better understand this seemingly painted moon, NASA directed the robotic Cassini spacecraft orbiting Saturn to swoop within 2,000 kilometers in 2007. Pictured above, from about 75,000 kilometers out, Cassini’s trajectory allowed unprecedented imaging of the hemisphere of Iapetus that is always trailing. A huge impact crater seen in the south spans a tremendous 450 kilometers and appears superposed on an older crater of similar size. The dark material is seen increasingly coating the easternmost part of Iapetus, darkening craters and highlands alike. Close inspection indicates that the dark coating typically faces the moon’s equator and is less than a meter thick. A leading hypothesis is that the dark material is mostly dirt leftover when relatively warm but dirty ice sublimates. An initial coating of dark material may have been effectively painted on by the accretion of meteor-liberated debris from other moons. This and other images from Cassini’s Iapetus flyby are being studied for even greater clues.
Last night’s launch of STS-128 (shuttle Discovery) was scrubbed due to lightning, as seen in the following pictures! Get the big versions here, they’re quite worth it.
CAPE CANAVERAL, Fla. — Xenon lights illuminate the rain falling on NASA Kennedy Space Center’s Launch Pad 39A at 1:24 a.m. EDT as space shuttle Discovery waits for a scheduled liftoff on the STS-128 mission. Launch was scrubbed due to the weather conditions, including lightning, that violated the limitations for liftoff. Another launch attempt is scheduled for 1:10 a.m. Aug. 26. Discovery’s 13-day mission will deliver more than 7 tons of supplies, science racks and equipment, as well as additional environmental hardware to sustain six crew members on the International Space Station.
The above image is pretty far off (though gorgeous), so here’s a close-up, showing shuttle, pad, xenon lights and lightning:
At this point my astronomy picture folder exceeds 750 items, yet what caught my eye tonight is actually last Wednesday’s APOD, a lovely image by Thomas W. Earle. What I love about images like this is the deepness of the sky, the abundance of stars, the richness of the… fabric of space. You really need to see it large to get the full effect.
Sprawling across hundreds of light-years, emission nebula IC 1396, visible on the upper right, mixes glowing cosmic gas and dark dust clouds. Stars are forming in this area, only about 3,000 light-years from Earth. This wide angle view also captures surrounding emission and absorption nebula. The red glow in IC 1396 and across the image is created by cosmic hydrogen gas recapturing electrons knocked away by energetic starlight. The dark dust clouds are dense groups of smoke-like particles common in the disks of spiral galaxies. Among the intriguing dark shapes within IC 1396, the winding Elephant’s Trunk nebula lies just right of the nebula’s center. IC 1396 lies in the high and far off constellation of Cepheus.