Notes about astronomy

December 28, 2010 permalink

Cryovolcano on Titan

Volcanoes spewing ice and slush instead of lava on Titan! From NASA: Cassini Spots Potential Ice Volcano on Saturn Moon

Scientists have been debating for years whether ice volcanoes, also called cryovolcanoes, exist on ice-rich moons, and if they do, what their characteristics are. The working definition assumes some kind of subterranean geological activity warms the cold environment enough to melt part of the satellite’s interior and sends slushy ice or other materials through an opening in the surface.

I suddenly have a hankering to play Metroid…

October 20, 2010 permalink

Physicist’s Goodnight Moon

What happens when a physicist considers the passage of time in Goodnight Moon? Chad Orzel, physics professor and blogger, attempts to measure it using the illustrated passing of the moon versus the wall clocks:

These two methods clearly do not agree with one another, which means one of two things: either I’m terribly over-analyzing the content of the illustrations of a beloved children’s book, or the bunny’s bedroom is moving at extremely high velocity relative to the earth, so that relativistic time dilation makes the six-minute rise of the moon appear to take an hour and ten minutes. Calculating the necessary velocity is left as an exercise for the interested reader.

(Photo credit: Chad Orzel)

August 29, 2009 permalink

The Full Moon Appears as a Tarte

“Harriot regularly corresponded with friends who were also trying out telescopes. One wrote to him saying that the full moon ‘appears like a tarte that my cooke made me the last week’.”

— A note from the “Cosmos and Culture: how astronomy has shaped our world” exhibit at London’s Science Museum, describing this first-ever drawing through a telescope, created circa 1610 by English mathematician Thomas Harriot.

Note to Austinites: the excellent Harry Ransom Center at UT will soon be opening their exhibit “Other Worlds: Rare Astronomical Works”, featuring some beautiful drawings by the likes of Cassini, Kepler, and Brahe. Can’t wait.

June 10, 2009 permalink

NASA Apollo 11 Haynes Owners’ Manual

In honor of the 40th anniversary of the Apollo 11 moon landing, Haynes (maker of popular do-it-yourself auto repair manuals) has published an “owner’s manual” for the various craft involved in the Apollo 11 mission. Includes information on the Saturn V rocket, the Command/Service module (the part that astronaut Michael Collins was stuck in while Neil Armstrong and Buzz Aldrin got to go play on the moon), and the Lunar module. If you want to get me something retroactively for my 10th birthday, I think this would be it. (Via El Reg)

May 27, 2009 permalink

2009 Texas Star Party Time Lapse

Time lapse video of night sky as it passes over the 2009 Texas Star Party in Fort Davis, Texas. The galactic core of Milky Way is brightly displayed. Images taken with 15mm fisheye lens.

Your camera can pick up some neat things if you swap out or remove the filters that they put between the lens and the sensor…