Astronomy Picture of the Day -- Sunrise at Tycho

NASA ^ | January 04, 2012 | (see photo credit)

[SunkenCiv]

Explanation: Tycho crater's central peak complex casts a long, dark shadow near local sunrise in this spectacular lunarscape. The dramatic oblique view was recorded on June 10, 2011 by the Lunar Reconnaissance Orbiter. Shown in amazing detail, boulder strewn slopes and jagged shadows appear in the highest resolution version at 1.5 meters per pixel. The rugged complex is about 15 kilometers wide, formed in uplift by the giant impact that created the well-known ray crater 100 million years ago. The summit of its central peak reaches 2 kilometers above the Tycho crater floor.

[SunkenCiv]

[Credit: NASA / GSFC / Arizona State Univ. / Lunar Reconnaissance Orbiter]

[SunkenCiv]

A Celestial Collision · Alaska Science Forum ^ · February 10, 1983 · Larry Gedney · Posted on 09/15/2004 9:04:28 AM PDT · by SunkenCiv -- Early in the evening of June 18, 1178, a group of men near Canterbury, England, stood admiring the sliver of a new moon hanging low in the west. In terms they later described to a monk who recorded their sighting, "Suddenly a flaming torch sprang from the moon, spewing fire, hot coals and sparks." In continuing their description of the event, they reported that "The moon writhed like a wounded snake and finally took on a blackish appearance"... [P]lanetary scientist Jack Hartung of the State University of New York... gathered enough clues to suggest that a large asteroid... might have smacked into the moon just over the horizon on the back side. To test his suspicion, Hartung went to the Lunar and Planetary Institute in Houston, and inspected Russian and American photographs of the moon's back side. Sure enough, in just the right place, he found a remarkably fresh crater, 12 miles across and twice as deep as the Grand Canyon. From it radiated white splatter marks for hundreds of miles... Such an impact, reason astrophysicists, would set the moon to ringing like a gong for thousands of years... At Texas' McDonald Observatory, astronomers Odile Calame and J. Derral Mulholland of the University of Texas find that the surface of the moon moves back and forth fully 80 feet! Such an oscillation clearly implies a collision with something large, sometime within the not-too-distant past, probably within the memory of mankind. The problem is that there is no way to peg the date exactly at 1178.

[SunkenCiv]

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[cripplecreek]

Rough territory but its a neat pic.

[RitchieAprile]

what a remarkable observation! eccentric rotation due to imbalance of mass about the center of rotation, i suppose..

[doorgunner69]

No one around to see it back then, but what a show that must have been when Tycho was formed. Would scare the beejus out of us today............

[Boogieman]

Sunrise near Tycho crater? Uh oh... does anyone else hear that ringing noise?

[Prospero]

And here's a detail, a full-resolution crop from the same LROC NAC observation, showing the 100 yard boulder perched on the very top of the central peak of Tycho:

[Prospero]

And more detail of that boulder, from LRO overflights captured at nadir rather than oblique:

If LRO ends up being the only surviving part of the Vision for Space Exploration, it will have been a noble one.

Nothing has stayed in lunar orbit for so long a time, and long ago the sheer amount of data returned from the mission surpassed that of all deep space missions combined.

At this hour, LRO is traveling through its 16,129th orbit orbit around the Moon.

[SunkenCiv]

The date of the Tycho impact is based on thin air. :’) IOW, we don’t know whether someone was around to see it or not.

[SunkenCiv]

Some of the “pulse” of the lunar surface is due to tidal forces acting on it from the Earth (and Sun, for that matter), but remarkably, a lot of it is due to some large impact or other, and it may have been this 12th c one, or one more recent, or a larger one longer ago.

[SunkenCiv]

;’)

[SunkenCiv]

Thanks!

[SunkenCiv]

Nice! Appears to be ejecta. Oooh, the pics just vanished as I posted this.

[Slyfox]

Top down view:

[jmacusa]

Tycho is always easy to see in telescopes. What is interesting are the three channel-like grooves extending from the impact crater. What ever hit Tycho at least three large chunks of it made this feature.

[Moonman62]

A major them of 2001 is the homicidal nature of man. Someone noted that the excavation site at the WTC looked a lot like that excavation site in the movie.

[Prospero]

The date of 109 million years is based on samples retrieved by Harrison Schmitt at Taurus Littrow in 1972. The pressure-front from the impact is theorized to have encountered South Massif, casting down the bright Tortilla Flat albedo spread upon the Lee-Lincoln lobate scarp.

Not precisely "thin air," but more directly than than is more common.

And here's a bonus. The Tranquility "skylight" pit crater first photographed by the LROC NAC system in recent years:

[SunkenCiv]

Thanks again, Prospero.

On the Moon with Apollo 17: A Guidebook to Taurus-Littrow
by Gene Simmons (not the guy from Kiss)
http://www.hq.nasa.gov/alsj/a17/a17OTM.html

[SunkenCiv]