How Fast is Sound?

A few months ago, I read an article in The Physics Teacher (published by the American Association of Physics Teachers) on measuring the speed of sound using a couple of microphones hooked up to a computer's line-in jack.  Apart from having to make a trip to Radio Shack to buy some parts to convert two standard unpowered microphones into a pair of powered microphones for stereo input, the process was amazingly straightforward.  I did a quick proof-of-concept in the dining room one evening and go

Globe-at-Night Survey Wants You!

The Globe-at-Night program is an annual program where you (yes, you) can help by providing data on the visibility of stars in the night sky. Your role as an amateur scientist is to make some observations (details on their web site), record the results, and submit them to the Globe-at-Night program. Your observations, along with those of thousands of others around the planet, will be combined to provide information on the impact of night-time lighting on the sky.

Milky Way Gets a Little Bigger

There's a New York Times Science article from yesterday reporting on recent measurements indicating that the Milky Way, our home galaxy is bigger than previously thought. We now qualify as a peer of the Andromeda galaxy. The critical measurement was how fast we revolve around the galactic center. The faster we're going, the more massive our galaxy must be to hold us in.

Math Evolver, needs to evolve a bit more....

Math Evolver is a game by DimensionM used to teach pre-algebra to middle school students.  While perhaps not quite as exciting as Halo, its very good.  Good enough that my older son is willing to actually think in order to play the game (at least when I won't let him play Halo which, of course, requires very little thinking).

Moon, Jupiter, Venus Conjunction

Well, I'm a bit late putting this up, but I took some pictures last Monday night of the conjunction between the crescent moon, Jupiter and Venus. 

[img_assist|nid=819|title=Moon, Jupiter, Venus Conjunction, 2008-12-01|desc=|link=none|align=undefined|width=640|height=479]

 

The image was taken with a Canon 350D (Digital Rebel XT) and a 70-300mm zoom at around 200mm focal length. The insert shown is Jupiter and two of its moon can be clearly seen.

Pages

Subscribe to astrofoto.org RSS