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New Moon:
August 5
Full Moon:
August 19
DEEP SKY OBJECTS (DSO's) (Not
the biggest or best, but interesting) :
Minkowski 2-9 (aka: The Butterfly
Nebula, or PK 10+18.2): This planetary nebula was made famous by a beautiful
Hubble Space Telescope photograph. It's faint, at magnitude 13.2, and a larger
telescope and high power (~550x) is needed to resolve the nebula into it's two
elongated lobes and it's central star. It is thought to be very young, created
about 1,500 years ago. In August, look for Minkowski 2-9 early in the night before
it gets too close to the western horizon (It is 42 degrees above the horizon when
astronomical twilight ends at 9:58pm). Also, this nebula is pretty far into the
southern sky, located not far above the top of Scorpius. We could not find it
thru an 11" telescope using a narrow band filter, so we recommend trying
at least a 14" scope with an OIII filter. Good luck! Size: 60"x30"
(Location: 17hr 05m 38s RA -10 deg 08.5' Dec, in Ophiuchus).
Humason 1-2 (aka: PK 86-8.1): Planetary nebula. Magnitude 12.7. A medium sized scope (10") should show an hourglass figure at about 400x. Size: 8.3" (Location: 21hr 33m 08s RA +39 deg 38' 04" Dec, in Cygnus. 3 degrees east of Sigma Cygni).
An OIII (Oxygen 3) filter, or even a narrow band filter, will improve the view of the 2 planetary nebulae above. (OIII filters are usually not used on telescopes less than 8" diameter because these filters block so much of the light.)
Supernova
in M51 (Whirlpool Galaxy): a 14.0 magnitude supernova in this 8.5-magnitude
spiral galaxy was discovered on June 28th by Wolfgang Kloehr, an amateur astronomer
in Germany. The galaxy is relatively nearby at 15 light years away.
M51 is
40 degrees above the western horizon when astronomical twilight ends in mid-August.
See this article
in S&T for more information and photos to identify the supernova. (Location:
13h 29m 52s.85 RA +47°10'36".3 Dec in Canes Venatici)
Supernova in Galaxy NGC2403: This super nova has faded to magnitude
15.9, but was magnitude 11.2 when discovered in July 2004 (yes, 2004) by an
amateur astronomer in Japan. This magnitude 8.9 galaxy is also known as Caldwell
7, and, per The Night Sky Observer's Guide, was the first galaxy beyond
our Local Group in which a Cepheid variable was discovered. This supernova has
dimmed so much that it will take either an 18" telescope under perfect
conditions or a camera on a smaller telescope to see it.
NGC2403 is too low in the west in the evenings
this month, but, buy the end of this month, is 33 degrees above the eastern horizon
when astronomical twilight begins in the morning. So the last hours of darkness
will be the best time to find this supernova and, as the year goes on, NCG2403
will be higher and higher in the morning sky. By the end of September, NGC2403
will be 50 degrees above the eastern horizon when astronomical twilight begins
in the morning. See this article
in S&T for a sky chart & photo to identify the supernova.(Location: 07hr
36.9m +65deg 36' in Camelopardalis)
See this link
to Rochester's Astronomy Club for more information on finding and viewing
supernovae.
MONTHLY STAR GAZE (August
5):
Sun: Sets at 8:29pm, astronomical twilight ends
at 10:10pm and begins at 5:03am the next morning. The Sun rises the next morning
at 6:39am. Between astronomical twilights, we get only 6.9 hours of darkness.
Moon: (illuminated
1%) The Moon sets at 9:11pm on the night of the gaze.
Mercury: Not a good time to view.
Venus: 19 degrees above the western horizon at sunset at magnitude -4.0. It's almost fully illuminated (82%), so there is not much of a pretty crescent shape to observe. Realize that because Venus is in the evening sky it is approaching Earth, and will soon come between the Sun & the Earth.
Mars: Rises at 12;16am at
magnitude -0.6, it's diameter is only 12 arc seconds. It's apparent size will
increase during the summer, reaching 20.2 arc seconds in late October. At this
time Mars will be the closest it will be for the next 13 years. It will be much
higher in the sky than it was during it's 2003 approach, so will appear smaller
but sharper in telescopes.
Jupiter & it's moons: Jupiter is 31 degrees above
the horizon at sunset, heading down towards the western horizon. It appears
quite large, at 34 arc seconds. There are no Jovian-moon events tonight.
Saturn: Saturn rises at 5:51am, about 30 minutes before the Sun, so it's not a good time to observe.
Asteroids: Ceres culminates at 8:29pm. You can see it in binoculars as a faint star-like object at magnitude 8.6 in the constellation Libra. (Location at midnight:15hr 53.9m R.A. -15 deg 3.97m Dec. See the chart on page 56 of the May Sky & Telescope.)
Satellites:
There are no Iridium Flares this evening
These
predictions are for Mt. Pisgah. Flares will be slightly different from Asheville.
The
Hubble Space Telescope begins a magnitude 3.0 pass at 05:07:08am in the South
on August 6th. It heads towards the ESE and disappears at 5:11:10am.
See the
Heavens-Above web site.
HIGHLIGHTS:
Lammas
(a cross-quarter day): August 1st. See article
from the Clark Planetarium.
Perseid meteor shower: Peaks in the early morning hours
of August 12 & 13. The ZHR (Zenithal Hourly Rate) is 100, but a single observer
should expect to see no more that about 60 per hour. The quarter moon sets about
midnight, leaving the sky dark for the meteors. The best time to watch is from
midnight until twilight, when the meteor shower's radiant is high in the sky
and the moon has set. These meteors are sand and pebble sized debris from comet
109P/Swift-Tuttle. "There's a slight chance that a brief extra
peak, lasting perhaps a few hours, may arrive around 5 am EDT (Aug 12)... Mikiya
Sato in Japan calculates that at that time, Earth may pass through a streamer
of material that was shed from the Perseids' parent comet, Swift-Tuttle, during
its pass by the Sun in the year 1479. Last year's Perseid shower displayed a
very strong extra peak due to a similar streamer shed by the comet in 1862."
See article
in S&T.
TERMS:
AFOV=apparent field of view / dec=declination
/ EP=eye piece / FOV=field of view / ISS=International Space Station / HST=Hubble
Space Telescope / ly=light year / mag=magnitude / ra=right ascension /
culminates=transits the meridian=when an object as at its highest point in the
sky / transit=passing in front of another object / ZHR=zenithal hourly rate (basically,
the most meteors 1 person could see in 1 hour under ideal conditions)
CLUB STARGAZE:
You can check the AstroAsheville
Yahoo group [or call Tim @ 251-0040 or John @ 251-1933 (before 5:00) or 667-9268
(after 5:00)] for a go/no-go decision and to verify location.
CLUB MEETING:
Indoor club meetings are usually the first Thursday of every
month, at 6 p.m. in the Sims
Group offices (230 Short Coxe Ave., Asheville, NC.)
Happy Starwatching! Dress Warm! Blue Ridge Parkway Information
Line is 828-298-0398
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(Much of the above info is derived from Sky & Telescope magazine, Ottewell's
Astronomical Calendar, The Night Sky Observer's Guide, Burnam's Celestial Handbook,
Megastar 5.0, Planets202, Cartes du Ciel, the ol' Miller Planesphere, and a little
(very little) common sense.)