That’s No Moon, It’s … Oh, Wait, It’s a Moon

PIA 12570 — Mimas, the Death Star MoonSo the Death Star joke has been done to death, and Cassini’s 2010 photo of Mimas has become pretty much the standard picture for the second smallest of the planemo (planetary-mass object) moons around Saturn, which has enough moons that astronomers haven’t finished naming them all.

JPL explains the famous Death Star picture:

Herschel Crater is 130 kilometers, or 80 miles, wide and covers most of the right of this image. Scientists continue to study this impact basin and its surrounding terrain (see PIA12569 and PIA12571).

Cassini came within about 9,500 kilometers (5,900 miles) of Mimas on Feb. 13, 2010.This mosaic was created from six images taken that day in visible light with Cassini’s narrow-angle camera on Feb. 13, 2010. The images were re-projected into an orthographic map projection. This view looks toward the area between the region that leads on Mimas’ orbit around Saturn and the region of the moon facing away from Saturn. Mimas is 396 kilometers (246 miles) across. This view is centered on terrain at 11 degrees south latitude, 158 degrees west longitude. North is up. This view was obtained at a distance of approximately 50,000 kilometers (31,000 miles) from Mimas and at a sun-Mimas-spacecraft, or phase, angle of 17 degrees. Image scale is 240 meters (790 feet) per pixel.

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Science and Star Wars

The Death of Admiral OzzelAs Star Wars fever heats up toward its inevitable pandemic in 2015, when J. J. Abrams is slated to release the yet-untitled Chapter VII, the first symptoms are already apparent over at Wired Science, where physics professor Rhett Allain reflects on his Reddit AMA session discussing the science of the cinematic saga. Actually, he’s giving out homework:

• How hot is a light saber? (from roguepublichealth) I think you have to first figure out what a light saber actually is and why it glows.

• How much material would be needed to build the Death Star (from astanisic) You will obviously need some estimates here. If you want a second question, how long would it take to put this Death Star together. You can answer for both the first (Episode IV) and second (Episode VI) Death Stars – which are different sizes.

The physics of choking someone to deathAnd so on. In truth, it’s not one of his better Dot Physics posts, but only because he’s asking the questions and not explaining the answers. For instance, there is more to learn from his consideration of the vital question, “How much does Darth Vader weigh?”

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