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The following is discussion of some astronomical objects that may be seen in the sky this week, Sept. 7 to Sept. 13, 2008.

International Space Station

For the Denver area the passes early in the week are low in the north, brief, and not bright. Later in the week the circumstance improves. On Thursday Sept. 11 the ISS appears in the NW at 5:51 am and disappears in the ESE at 5:56. It will reach magnitude -1. The brightest pass is on Fri morning at 6:17. It appears in the WNW and disappears in the southeast. It will reach magnitude -2.1

On Sat. Sept 13 it appears at 5:10 am in NNW and disappears in the ESE. It will reach magnitude -1.3.

On Sun. morning Sept 14 it appears in the WNW at 5:36 am and disappears in the SSE at 5:41 am MDT

Most ISS passes are easy to see as they are quite bright but they are easy to miss as they only last a few minutes. The times it is visible and direction depends on your location. Check www.heavens-above.com for times that the ISS is visible over your location.

Sun

On Sunday Sept. 7 sunrise is at 6:37 am and sunset is at 7:34 pm MDT

On Saturday Sept. 13 sunrise is at 6:42 am and sunset is at 7:15 pm MDT

There a no active regions visible on the solar disk as of Sunday.

Moon

On Sunday evening the moon is at first quarter at 8:07 am (lunation 8.3)

On Saturday evening the moon is at lunation 14.3 . It will be full next sunday Sept 15 at 3:13 am

Planets

Mercury, Venus, and Mars are low in the west in bright twilight about a half hour after sunset.

Jupiter is straight south about 8:30 pm. It sets at 1:29 am on Sunday and 1:05 am by Saturday.

Jupiter's great red spot crosses the center of the disk at the following times this week:
Sun. Sept 7 at 9:17 pm
Tues Sept 9 at 10:56 pm
Fri Sept 12 at 8:26 pm MDT

Neptune is constellation Capricornus. It is magnitude 7.8 in brightness and its disk is only 2.4 arc sec across. It is 29.1 a.u. or 2.7 billion miles away.

Uranus is in constellation Aquarius. It is at opposition on Friday Sept. 12. It is magnitude 5.7 in brightness and its disk is 3.7 arc sec across. It is 19.1 a.u. or 1.8 billion miles away. Unlike other planets, Uranus rotates almost perpendicular to the orbital orbital plane. One pole points near the star Eta Ophiucui and the other to the top of Orions bow.

Comets

The moon interferes with comet observations this week.

Asteroids

The asteroid 9 Metas crosses in front of the 6th magnitude star HIP 14764 on fri Sept 12 at 12:25 am. You will need to be south of downtown Denver to see it. for more info see the September issue of Sky and Telescope magazine p66 and www.asteroidocullation.com.

Dark Sky

Not this week.

Summary

This week you can view some bright passes of the International Space Station, watch Jupiter's great red spot cross the disk, view craters on the moon, and maybe watch a dim asteroid blank out a fairly bright star.