Friday, August 10, 2007
Peaking on Sunday night/Monday morning is the Perseid Meteor Shower. Every year about this time, our Earth sweeps through an old debris trail from Comet Swift - Tuttle. Grains of dust enters our planet's upper atmosphere at a staggering 40 miles per second. The tiny shock wave thusly generated heats the air around the grain, causing it to glow. This lasts for just a second or so.
To see this event, sit in a comfortable chair after 11:30 p.m. on Sunday night and face northeast, if you can. If you are lucky, the meteors zip by at a rate of 60 per hour. The source of the meteors on the celestial dome is just below the "w" of Cassiopeia.
Such is the view from Earth...
Thursday, August 9, 2007
For the next 6 months, bright red Mars stands out among the background stars of Taurus and Gemini. During August, it slides between two star clusters, the Hyades and the Pleiades. Look in the east about 4:00 a.m. As the weeks pass, Mars rises earlier and earlier, and by month's end it pops above the horizon before 12:30 a.m.
Compare its brightness and color with the star Aldebaran. In the coming months, Mars grows considerably brighter, eventually outshining Aldebaran by nearly 10 times.
Such is our view from Earth...