Here is another reason to wake up early on Saturday morning - a
rare meteor shower! Bright shooting stars should be visible even
with a big old bright moon, and our city light pollution. Look
to the East and Northeast.
"Some time in the 40 years
or so around 4 A.D., comet Kiess (C/1911 N1) passed by the Sun,
ejecting a cloud of dust particles. The comet returned in 1911, after
completing one orbit. The dust particles were pushed by the Sun's
light into slightly wider orbits and have been returning ever since,
forming a thin ongoing stream of dust that usually passes just outside
Earth's orbit. On occasion, the combined gravity of the solar system's
planets moves this dust trail into Earth's path. Earth encountered
this 2000-year-old dust in 1935, 1986, and 1994, causing a meteor
shower known as the Aurigids."
http://aurigids.seti.org/
Best viewing
direction:
Best viewing: Keep Moon out of field of view (best to block
behind obstruction such as telephone pole, then watch whole sky),
avoid city haze that scatters moonlight
Best direction: East and Northeast
Best time: Start one hour
before peak, then see the rate of meteors increase and decrease while
Earth travels through the shower
When:
Date: 2007 September 1
Peak time: about 11:33 +/- 20 minutes UT (= 04:33 a.m. Pacific
Daylight Savings Time).
Duration: about 1.5-hour
Width: 25 minutes above half the peak rate
What:
Peak rate: ZHR (Zenithal
Hourly Rate) = 200 per hour (10-minute interval)
Meteor brightness: mostly
-3 to +3 magnitude
Shower radiant: constellation Auriga (Radiant at RA = 92, Decl.
= +39)
Entry speed: Vinf = 67 km/s
Where:
Visible from: California, Oregon, Hawaii, Alaska, Mexico [see
flux applet for visibility from your location]
Moon:
4 days past Full Moon, high in
the sky
Important because:
Once in a lifetime crossing of
the dust trail of a known long period comet (comet Kiess).
Public interest:
When you make a wish, consider that each meteoroid was released at
some unknown moment during the period 36 B.C. - A.D. 45.
Links: NASA Ames News Release:
http://www.nasa.gov/centers/ames/news/releases/2007/07_59AR.html
--
Jane Houston Jones
Senior Outreach Specialist, Cassini Program
JPL - 4800 Oak Grove Drive, MS 230-205
Pasadena, CA 91109 818-393-6435
jane.h.jones@jpl.nasa.gov
Cassini SOC http://soc.jpl.nasa.gov/index.cfm
What's Up?
http://education.jpl.nasa.gov/amateurastronomy/index.html