THE GREAT TYCHO ZOOM 4-4
Photo Credit: NASA Lunar Reconnaissance Orbiter (LRO): CLICK for larger photo and look below for links and information.
This is the last step in our great Tycho Crater zoom, and as you can see we’re looking down onto that 400 ft. in diameter boulder. This May 27, 2010 LRO image is approximately 600 meters across and now you can tell by looking at the terrain that this mountain was formed very quickly, likely in seconds. On the floor surrounding the boulder (Which should have a name but I don’t think that it does) you can see the telltale signs of impact melt. You can also see fracturing as it appears that the peak is beginning to erode. Someday the peak will erode enough so this boulder will actually roll down the mountain to the crater floor 6562 ft. below. You may be wondering how that boulder got up there to begin with right? Well as I said, this mountain was formed very quickly upon impact. So fast in fact that it had already formed as the debris was falling back to the Moon’s surface. In the process this boulder fell back to the surface as well, directly into the saddle of our mountain’s peak. Ok, so that’s it for the Tycho zoom…….please let me know if you liked it and or if I should do more like it in the future.
Tycho Crater is a paraboloid shaped, complex impact crater on the Moon which bears the name of the great Danish astronomer Tycho Brahe. The name was given by Giovanni Riccioli whose 1651 lunar nomenclature system is todays standard. It was formed on the approximately 110 million years ago which is very young in astronomical terms. It’s approximately 51 mi (82 km) in diameter with a depth of 2.9 mi (4.8 km). When viewed through binocular or telescope the albedo alerts you to its young age as its interior and ejecta “spokes” or “rays” appear to overlay the surrounding environment as they stretch as long as 932 mi (1500 km), especially when in sunlight.
One of the most incredible features is the uplift or rebound area at the crater’s center known as the central peak. It stretches about 9.3 mi (15 km) and rises off the crater floor to a height of 6562 ft. while the crater floor itself lies 15,420 ft. (4700 m) below the rim.
The rigidity and sharpness to the structure also lends itself to a young crater as it hasn’t yet been worn away by micrometeorites as it will through the years (to see what this crater may look like in a billion years check out Bhabha crater). It’s believed but not proven that this crater was created from the Baptistina family of asteroids, caused by the breakup and multiple impacts of asteroid 298 Baptistina. That is the asteroid which is believed to have also created the 110 mi (180 km) wide Chicxulub Crater in the Yucatan Peninsula on Earth which ended the era of the dinosaurs. Note that it’s believed to be the same material, this doesn’t imply that it happened at the same time as it’s estimated that the Chicxulub Crater was formed approximately 65-66 million years ago.
To locate Tycho Crater, Northern Hemisphere sky watchers will want to look near the very bottom of the Moon while my upside down friends in the Southern Hemisphere will need to search near the top of the Moon. In both cases it will be the brightest most prominent crater in that region. Its selenographic coordinates are 43.37°S, 348.68°E.
NASA LRO page for this crater: http://lroc.sese.asu.edu/news/?archives/411-Tycho-Central-Peak-Spectacular!.html
Incredible NASA LRO Tycho peak interactive zoom: http://wms.lroc.asu.edu/lroc_browse/view/M162350671
Impact melt on Tycho floor: http://lroc.sese.asu.edu/news/index.php?/archives/319-Impact-melt-features-in-Tycho-craters-floor.html#extended