Published: 2013-08-09 19:39:00
Updated: 2013-08-10 08:25:16
Posted August 9, 2013
Updated August 10, 2013
By Tony RIce
The Perseid meteor shower is underway.
Sky watchers mark this week on their calendars not just because of the number of visible meteors (50+ per hour in optimal viewing conditions) but also because the Perseids are known for producing bright fireballs (meteors brighter than Venus) which, unlike other meteor showers, are visible in even light polluted skies.
All-sky cameras at the Pisgah Astronomical Research Institute (PARI) in western North Carolina caught a bright fireball last week. PARI cameras are part of NASA's All Sky Fireball network where more early Perseids have been captured.
The Perseids are expected to peak Sunday or Monday with the best viewing in the hours before sunrise.
Before midnight, we are on the trailing edge of the Earth's rotation. Less of the dust and rock debris that make up the tail of comet 109P/Swift-Tuttle, source of the annual Perseid meteor shower, enters the atmosphere. The amount of the debris increases as we rotate toward the sun making those few hours before the rising sun spoils the view the best time to watch.
Perseids appear to rain outward from the upper edge of the constellation Perseus, the Greek hero. The easiest way to find the radiant is to look in the northeast below Cassiopeia, which looks like a W tipped on end. Meteors may appear anywhere in the sky but tracing their paths back will bring you to Perseus.
The best viewing is away from city lights in an area where as much sky as possible is visible.
Even with a high rate of visible meteors and a reputation for producing bright fireballs, the Perseids could be hard to see if the forecast for cloudy skies holds throughout the the weekend.
A more sure bet may be to tune in to the live feed from NASA's all-sky cameras and all-night web chat with astronomers from the Marshall Space Flight Center and the Meteoroid Environment Office beginning Saturday evening.
Tony Rice is a volunteer in the NASA/JPL Solar System Ambassador program and software engineer at Cisco Systems. You can follow him on twitter @rtphokie.