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The following is a discussion of a few astronomical objects to see up in the sky this week, August 10 to August 16, 2008.

International Space Station

There are no visible passes over the Denver area this week.
Check www.heavens-above.com for times specific to your location.

Sun

Sunrise on Sun. Aug. 10 is at 6:10 am
Sunset on Sun. Aug. 10 is at 8:06 pm mdt
(for those of us at 40 degrees north latitude)

Sunrise on Sat. Aug. 16 is at 6:16 am

Sunset on Sat. Aug. 16 is at 7:58 pm mdt

There are no active regions visible on the disk as of this Saturday evening, Aug 9.
For more information about the Sun and solar activity see www.swpc.noaa.gov

Moon

The Moon starts the week at lunation 9.8.
Some features to view are Mare Frigoris, Promitorium Laplace, Mare Imbrium, Copernicus, Bullialdus, Palus Epidarum, and Longomontanus

On Monday, lunation is 10.8. Targets are Sinus Irridum, Promotorium Heraclides, Kepler, Mare Humorum, Gassendi, and Hippalus

On Tuesday, lunation is 11.8. Lunar1 targets are Vallis Shroter,Aristarchus, Oceanus Procellarum, and Billy

On Wednesday, lunation is 12.8. Targets are Sinus Roris, Reiner Gamma and Shickard.

The moon is full on Saturday Aug 16 at 3:16 pm MDT
For more information about the Astroleague Lunar 1 club, see http://www.astroleague.org/al/obsclubs/lunar/lunar1.html

Planets

Mercury, Venus, Mars, and Saturn are all difficult to see in the bright twilight after sunset. Look for them with binoculars close to the horizon about a half hour after sun down.

The planet Jupiter is visible in the southeast as the sky darkens. It is visible straight south at 10 pm and easy to find as it the brightest object visible at that the time other the moon. It is currently magnitude -2.4 and the disk is 45 arc sec across as seen with telescopes on Earth. It is currently 405.5 million miles from Earth.

The great red spot crosses the disk at the following times this week:

Mon. evening Aug 11 at 11:57 pm

Thurs. morning Aug 14 at 1:36 am

Thurs. evening Aug 14 at 9:27 pm

Sat. evening Aug 16 11:05 pm MDT (excellent position)

For more information about GRS crossing times see www.skyandtelescope.com

Neptune is at opposition on Aug 15th in constellation Capricornus. It is currently magnitude 7.8 in brightness.Its disk is only 2.3 arc sec across as seen from telescopes on earth. It is 2.7 billion miles from Earth. In 1846 the existence of the planet and its position was predicted by French mathematician Urban LeVerier who was studying perturbances in the orbit of the planet Uranus. He sent his predictions by mail to Johann Galle at the Berlin Observatory. It arrived five days later on Sept. 23, 1846. John Galle observed the planet Neptune later that evening.

Uranus is in constellation Aquarius. It is currently magnitude +5.8 in brightness and the disk is 3.7 arc sec across. It is 1.8 billion miles away.

Meteors

The Perseid meteor shower peaks in the early morning on Tues. Aug 12. The moon sets at 1:43 am which is fortunate as the best meteor observing period will be about 2 am to 4:30 am. The usual estimate at the peak of the Perseid meteors is 60 to 100 per hour from a dark sky location. Only the very brightest ones will be be visible from light polluted urban areas. For more information about meteors and how to view them see www.amsmeteors.org and the Astroleague's meteor club at http://www.astroleague.org/al/obsclubs/meteor/metrcl.html

Comets

Look for comet C/2007 W1 Boattini early in the morning before moonrise as the week begins. It is about magnitude +8 and the coma is about 12 arc minutes across so it may be seen in binnoculars, finders, and small telescopes. Bright moonlight interferes with our observations of comets most of this week. For sky charts and more information about comets see www.skyhound.com or www.aerith.net Also, checkout the Astroleague's comet observing club at http://www.astroleague.org/al/obsclubs/comet/comet.htm

Summary

This week is a good time to observe craters and other features on the moon, to view Jupiter's great red spot, and to watch the annual Perseid meteor shower. For more information on how to observe some of the fascinating objects in our universe, attend a meeting at a local astronomical society in your area. There are 297 astronomy societies across the United States so there is probably one near you. Check www.astroleague.org for more information. If you happen to be in Colorado front range area, stop at next the Longmont Astronomy Club meetings and say hi! See www.longmontastro.org