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The following is a brief discussion of just a few of the many astronomical objects that can be seen during this week, Aug 24 to Aug 30, 2008.

International Space Station

The International Space Station is visible in the Denver area at the following times this week:
Mon. morning Aug 25 at 6:08 am the ISS appears in SSW and disappears in ENE at 6:13 am reaches -0.6
Wed. morning Aug 27 at 5:28 am it appears in SSW and disappears in ENE at 5:33 am
Thurs. morning Aug 28 at 5:55 am the ISS appears in WSW and disappears in NE at 6:00 am
Fri. morning Aug 29 at 4:50 am it appears in SSE and disappears in ENE at 4:53 am

The International Space Station is bright and usually very easy to see but it moves quickly and is only visible for a few minutes so it is also easy to miss. Whether it is visible or not, its position, and when it appears varies widely depending on your location.

Hubble Space Telescope

In the Denver area the Hubble Space Telescope can be seen low in the southern sky. It appears in southern part of constellation Scorpius and crosses to Sagittarius.

Wed. Aug 27 at 9:05 pm in the SSW and disappears in the south at 9:06 pm (magnitude 3.8)
Thurs. Aug 28 at 9:03 pm in the SSW and disappears in the south at 9:05 pm (magnitude 3.6)
Fri. Aug 29 at 9:01 pm and disappears in the south at 9:03 pm (magnitude 3.5)
Sat. Aug 30 at 8:59 pm and disappears in the south at 9:02 pm (magnitude 3.5)

Check www.heavens-above.com for times when the Hubble or ISS are visible at your location.

Sun

On Sunday Aug 24 sunrise at 6:23 am and sunset at 7:46 pm mdt
On Saturday Aug 30 sunrise at 6:29 am and sunset at 7:37 pm mdt

There are no sunspots visible on the solar disk as of Sunday. See www.swpc.noaa.gov for more current information about solar activity (or the lack thereof).

Moon

The moon is at lunation 23.8 on Sunday Aug 24 and is new on Saturday Aug 30 at 1:58 pm mdt

Planets

Mars, Venus, and Mercury are low in the west in bright twilight about a half hour after sunset. Venus is quite bright at magnitude -3.8 and is 10.8 arc sec across. You'll probably need binoculars to spot Mars and Mercury.

Jupiter is straight south and about 25 degrees above the horizon around 9:20 pm. It is the brightest object in the sky at that time at magnitude -2.4. It is 44 arc sec across as viewed by telescopes here on Earth. It is 4.52 astronomical units or 420 million miles away. The Great Red Spot is a giant storm that has been raging in the atmosphere of Jupiter for perhaps hundreds of years. It crosses the center of the disk at the following times this week Tues morning Aug. 26 at 1:30 am (low)
Tues evening Aug 26 at 9:22 pm (high up, excellent position)
Thurs. evening Aug 28 at 11:00 pm
Sun. morning Aug. 31 at 12:38 am

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 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

Dark Sky Objects - Planetary Nebula

IC5146 is located in the northeastern part of Cygnus. Althogh its 10th magnitude this is a tough object to view in the eyepiece. It appears as round diffuse haze even in larger telescopes. A hydrogen-beta filter may improve contrast and make some of the dark lanes visible. You need quite dark skies to view this object.

Much easier to see is another planetary in Cygnus, NGC 6826. This is a great object to view, especially in scopes in the 10-12 inch range. The brightness of the central star overwhelms your view causing the surrounding nebula to disappear. Look away from the central star and the nebula re-appears giving this object its descriptive name, "the blinking planetary"

Comets

C/2007 W1 Boattini is in constellation Aries. It is magnitude 8.9 in brightness so you may be able to see it in binoculars and small telescopes. Its coma is 11 arc min across.

6P/d'Arrest is in constellation Capricornus. It is magnitude 11 in brightness. Coma is only 1 arc min across so it may be difficult to identify.

C/2008 J1 Boattini is constellation Ursa Minor. It is magnitude 10.8 in brightness and coma is 4 arc min across

19P/Borrelli is in constellation Cancer. It is magnitude 10.9 in brightness and coma is 1 arc min across.

15P/Finley is in constellation Gemini. It is magnitude 11.8 in brightness and the coma is 3 arc min across

C/2007 N3 Lulin is in constellation Ophiuchus. It is magnitude 11.3 and coma is 1 arc min across

C/2006 OF2 Broughton is in constellation Camelopardalis it is magnitude 11.2 and coma is 2 arc min across

17P Holmes magnitude 7.5 and com is 1 degree degree across. It is still low and due to large size it will be difficult to view.

See www.aerith.net or www.skyhound.com for charts and more information about comets. Also check the Astroleague's Comet club at http://www.astroleague.org/al/obsclubs/comet/comet.htm

Summary

This week you can observe the International Space Station in the early morning; view the Hubble Space Telescope in the evening; observe Jupiter's Great Red Spot cross the planets disk; and observe faint nebulas, galaxies, and comets.