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The following is a discussion of some of the astronomical objects that may
be seen up in the sky this week, Aug 3 to Aug 9, 2008.

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You may subscribe at the iTunes store (640x480 pixels, 85 megabytes) or download a HD 720P high resolution version of this astronomy video from the Astroleague website (1280x1024 pixels, 280 megabytes). NOTE - uploaded incorrect low res version; that has been corrected Aug 7, 2008 9 pm - VR

International Space Station

The ISS makes some bright passes over the Denver area each night this week
through Friday.
Sun. Aug 3 at 9:45 pm ISS appears in the NW and disappears in the earth shadow in 9:49 pm in the east (reaches magnitude -2.2)

Mon.Aug 4 at 8:36 pm ISS appears in the north-northwest and disappears at
8:41pm in the east (reaches magnitude -0.6)


at 10:11 pm it appears in the
west-northwest and disappears in west-southwest into the earth shadow at
10:14 pm (reaches magnitude -0.8)

Tues Aug 5 at 9:02 pm it appears in the
northwest and disappears at 9:07 pm in the east-southeast (reaches
magnitude -2.3)

Wed Aug 6 at 9:28 pm ISS appears in west-northwest and
disappears in the south into the earth shadow at 9:32 pm (magnitude -0.9)

Thurs Aug 7 at 8:18 pm it appears in the northwest and disappears in the
southeast at 8:24 pm (magnitude -0.4)

Fri Aug 8 at 8:44 pm it appears in
the west-northwestand disappears at 8:49 pm in the south-southeast
(magnitude -0.5).

Check www.heavens-above.com for times that the ISS is
visible over your location.

Sun

On Sunday Aug 3, 2008 sunrise is at 6:03 am sunset is at 8:14 pm MDT>

On Saturday Aug 9, 2008 sunrise is at 6:09 am sunset is at 8:07 pm MDT

As of Sunday evening there are no active regions visible on the solar
disk.

For more information about the sun and space weather see www.swpc.noaa.gov

Moon

On Sunday the moon is at lunation 2.7 and will appear as a thin crescent
visible low in the west near the planet Mars

Mon Aug 4 Lunation 3: Endymion, Cleomedes, Mare Crisium, Picard,
Vendelinus, Petavius, Petavius Wall, Furnerius

Tues Aug 5 Lunation 4: Atlas, Macrobius, Proclus, Palus Somni, Messier,
Messier A, Fabricius

Wed Aug 6 lunation 5: Lacus Mortis, Posidonius, Mare Tranquillitatis,
Theophilus, Mare Nectaris, Fracastorius, Piccolomini

Thurs Aug 7 lunation 6: Aristoteles, Eudoxus, Mitchel, Mare Serenitatis,
Plinius, Cyrillus, Catharina, Gemma Frisius, Maurolycus

Fri Aug 8 lunation 7: First quarter moon at 2:20 pm MDT. Cassini, Cassini
A, Aristillus, Mons Piton, Montes Alpes, Vallis Alpes, Autolycus, Palus
Putredinis, Mons Hadley, Manilius, Mare Vaporum, Hipparchus, Albategnius

Sat Aug 9 Lunation 8: Lunar1 targets: Mare Frigoris, Mare Imbrium,
Copernicus, Bullialdus. Longomontanus

Planets

Venus, Mars, and Saturn are all very low and difficult to see in the bright western sky after sunset. Look for them with binnoculars around 8:40 pm

Jupiter is still in great position for viewing. It may be seen the
twilight in the southeast after sunset. Around 11 pm it is nearly
straight south and may be easily found as it is the brightest object
visible at that time.

The great red spot crosses the center of the disk at the following times
this week: Monday morning Aug 4 at 3:20 am (very low) Monday evening Aug
4 at 11:12 pm (excellent)

Thursday morning Aug 7 at 00:50 am Thursday evening Aug 7 at 8:40 pm

Saturday morning Aug 9 at 2:28 am (low) Saturday evening Aug 9 at 10:19 pm

Use a high magnification eyepiece and a light blue filter to increase
contrast and make the giant spot more visible.

Tues morning Aug 5, Jupiter's moon Io transits the disk starting at 2:26 am followed by its shadow at 3:04 am MDT

Thursday evening Aug 7, Europa may be seen crossing the disk from 10:21 pm to 11:05 pm MDT

For more information about Jupiter red spot and moon transits see
www.skyandtelescope.com

Neptune is in constellation Capricornus and is at opposition next week on
Friday Aug 15. It is magnitude +7.8 in brightness. On Thursday it is
located 9 arc minutes south of star 42 Capricorni. Neptune is currently
2.7 billion miles from Earth. Its disk is 2.3 arc sec across as seen by a
telescope here on earth.

Comets

Easiest to find comet this week is C/2007W1 (Boattini). It is magnitude
8.1 in brightness so you can see using your finder or binoculars. It is
beautiful to view through your scope and is quite recognizable as its coma
is around 11 or so arc minutes across. It is in the constellation Aries
so look for it before morning twilight begins (around 4:30 am).

A bit more difficult to find is the second comet discovered
Boattini , C/2008J1 (Boattini). It is
magnitude +10.5 and located 4 degrees southeast of Polaris in
constellation Cepheus on Aug 9. The coma is about 5 arc minutes across.

C/2006 OF2 (Broughton) is in constellation Perseus. It is magnitude +11
and coma is 2 arc minute across. Use imaging techniques as the coma may be
difficult to recognize. Best time to locate it is in the early morning as
well.

Look for C/2007 N3 (Lulin) early in the week just after moonset in the
constellation Sagittarius. The comet is magnitude +11.6 and the coma is
1.5 arc minute across. Use imaging techniques as the coma may be difficult
to recognize.

For charts and more information about comets see cometchasing.skyhound.com and aerith.net

Meteors

The Perseid meteor shower intensifies this week and will provide a great
show from dark sky locations. Best time to watch for them is in the early
morning say 2 to 4:30 am. The Perseid meteor shower began July 27th, will
peak on Aug 12, and continues through Aug 24. Perseid meteors are usually
quite bright, fast moving, and occasionally leave trains that are visible
for a second or two.

Meteoroids are dust and small debris from a comet which continues along
the orbital path. When the debris strikes the Earth's atmosphere at very
high speed a shock wave is created in front of the debris body by rapid
compression of the air in front of it (ram pressure). This shockwave heats
the air and produces the streak of light we observe here on earth which
are called meteors. The heat from the highly compressed air in front of
the meteor quickly melts the surface and is removed by air flowing over it
by an ablation process. If the meteors observed here on earth are from the
same debris cluster, their movement across the sky will all point back to
a common point called the radiant.

The Perseid meteor shower is caused by from debris left by comet Swift-
Tuttle.The radiant is currently two degrees south of the double cluster,
NGC 869/884.

For more information about meteors see www.amsmeteors.org

Summary

To learn more about the many fascinating objects you may observe, stop by
a meeting your local astronomy clubs such as the Longmont Astronomical Society
see www.longmontastro.org for upcoming meetings and other events.