NASA's Dawn spacecraft obtained this image of the 329-mile diameter asteroid Vesta with its framing camera on July 9, 2011. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Look how nicely the asteroid Vesta is coming into focus in this picture taken by the Dawn spacecraft on July 9 from a distance of 26,000 miles. In addition to craters, numerous troughs are visible around the raised ‘bump’ below center. It’s only an educated guess, but this area looks like the site of the giant impact that excavated a 290-mile diameter crater centered near the asteroid’s south pole. Unfortunately, no addition information was included with the caption.
Vesta’s gravity is expected to ‘capture’ Dawn around midnight CDT Friday night. At that time the two will be 9,900 miles apart and 188 million miles from Earth. Once in orbit, the spacecraft will study and photograph the asteroid for one year.
The full moon rides low in Sagittarius tonight. If you extend a line some 3 'fists' to its upper left, you'll meet up with Altair. From there, you can find the Summer Triangle. Created with Stellarium
Closer to home, tonight and tomorrow night mark the time of July’s Full Buck Moon. For observers in the Western Hemisphere the moon will look a bit fuller tonight than tomorrow night, because the moment of full phase happens at 1:39 a.m. CDT tomorrow morning. By Friday night, the moon will be 3/4 day past full.
The Buck Moon is named for buck deer, which start to grow their velvety horns this time of year. You might also hear it referred to as the Thunder Moon, a fitting seasonal name if there every was. The moon will rise around sunset both evenings in the constellation Sagittarius.
By 10 ‘o clock, it’s up high enough in the southeastern sky to enjoy a moonlit walk. As you’re strolling along, you’ll notice the moon is divided into two main types of landscapes: the bright lunar highlands or original crust of the moon, that formed some 4.5 billion years ago, and the darker maria (MAH-ree-uh) or lunar seas. These lava-flooded basins are some 500 million to a billion years younger.
The crust of the moon solidified some 4.5 billion years ago and is covered with craters from the impact of meteorites and small asteroids. The darker areas or seas formed more more recently when lava filled large basins left by asteroid impacts.
Near the bottom or south edge of the moon is a brighter spot that can just be detected with the naked eye. That’s the 54-mile diameter Tycho, a relatively fresh crater surrounded by rays of impact debris that reflect brilliantly around the time of full moon. In Tycho’s center is a pointy mountain peak that stands about a 1.2 miles above the crater’s floor. Tycho’s features are unusually sharp and fresh, because the crater’s only about 110 million years old. Compare that to the several billion year age of the average lunar crater.
Tycho crater's central peak complex, shown here, is about 9.3 miles wide, left to right. A curious boulder is just visible as a white spot near the pinnacle. Credit: NASA Goddard/ASU
Recently, the Lunar Reconnaissance Orbiter (LRO) took a magnificent closeup picture of the peak that is a MUST SEE. While the image hints at the detail recorded by the probe, please click on it to see the high resolution version. The scene is so rugged and real it will really open up your eyes.
To see more photos, including closeups of the big boulder sitting in the saddle between peaks, click HERE.
hi bob, scrolled thru the more recent Comet E posts. can’t help but wonder where all the k—-ks come from. are you really involved in some kind of heavenly conspiracy? is some blcak hole about to devour the earth and you are keeping that info from us? can’t help but feeling a bit sorry for you at times, you are so patient. I know how I would react and it wouldn’t necessarily be gentle. do keep up the good work. your posts continue to be greatly informative.
Hi Bob,
Saw the full buck moon from Indonesia last night. Unfortunately, with it brightness and the haze in the air, I have not been able to see enough stars to recognize contellations. Hopefully before I leave, I can see some. It is so disorienting to see Scorpius straight overhead, but cool.
Wow, Tycho’s central peak is so rugged. I will have a new appreciation for what i am looking at the next time I see it in the telescope. The cracks near the boulder look like crevasses on a glacier. Perhaps the mechanisms of formation are similar.
Take care and thanks for your efforts in creating such a worthwhile blog.
Jim
Wow, Jim — in Indonesia? What fun. I see that ‘Bulan’ is their word for moon. Glad you still enjoy the blog, too. Since you’ve traveled so far, I hope the sky clears soon. Your crevasse description describes the cracks well. Maybe the heat from impact created a thick bed of melted rock which cracked when it cooled, especially on the downslope. Just a guess.