raben.com

The following is a discussion of just a few of the many fascinating astronomical objects to view this week, Oct. 5 to Oct. 11, 2008.

Sun

Sun. Oct.5 sunrise is at 7:03 am and sunset is at 6:39 pm mdt
Sat. Oct. 11 sunrise is at 7:09 am and sunset at 6:29 pm mdt

There are no active regions visible on the solar disk as of Sunday. For more information about the Sun and space weather, see www.swpc.noaa.gov

Moon

Sunday evening the moon is at lunation 6.7
First quarter is Tuesday at 3:04 am mdt.
Saturday the moon is at lunation 12.7

Planets

Venus can be seen naked eye, low in the west. It sets just before 8 pm this week. It very bright at -3.8 magnitude and its disk is 12.6 arc sec across.

Jupiter is straight south around 7:45 pm. It is magnitude -2.1 in brightness and the disk is 38.4 arc sec across. Jupiter sets from 11:44 to 11:23 pm this week. Jupiter's great red spot crosses center of the disk at the following times:

Oct 6 at 8:20 pm
Oct 8 at 9:59 pm
Oct 11 at 7:29 pm

Neptune is in constellation Capricornus; it is magnitude +7.9 in brightness; its disk is 2.3 arc sec across.

Uranus is in constellation Aquarius. It is magnitude +5.8 in brightness and the disk is 3.8 arc sec across as seen from telescopes on earth.

Saturn rises 4:48 to 4:27 am in constellation Leo. It is currently magnitude +1.2 in brightness and the planet's disk is 16.3 arc sec across.

Meteors

Activity from the Orionid meteor hour increases this week. Several minor radiants are active such as the Draconids, Delta Aurigids, and October Camelopardalids. Watch for them early in the morning this week after moonset.

The Orionids radiant is located 6 degrees northwest of Betegeuese. Orionid meteors move very fast. They peak on Oct. 21st but unfortunately the moon will interfere.

International Space Station

There are great passes of the International Space Station visible in the early evening this week:

Sun Oct 5 ISS appears in NNW at 8:13 pm and disappears in the earth shadow in the NNW at 8:16 pm (magnitude -1.6)

Mon Oct 6 ISS appears in the NNW at 7:05 pm and disappears in the East at 19:10 pm (magnitude -1)

Tues Oct 7 ISS appears in the NW at 7:30 pm and disappears in the earth shadow in the ESE at 7:35 pm (magnitude -2.4)

Wed. Oct 8 ISS appears in the WNW at 7:57 pm and disappears in the earth shadow in the South at 8:01 pm (magnitude -0.3)

Thur Oct 9 ISS appears in the NW at 6:47 pm and siapppears in the SE at 6:53 pm (magnitude -2.3)

Summary

This week you can view some bright passes of the International Space Station in the evening; view dazzling Venus low in the west after sunset; and watch the Orionids meteor shower. With a telescope you can watch Jupiters moons and view craters on the moon.

Discussion of some astronomical objects that may be seen during the week of July 20 to July 26, 2008.

You may subscribe at the itunes store (640x480 pixels, 55 megabytes) or download a HD 720P high resolution version of this astronomy video from the Astroleague website (1280x1024 pixels, 174 megabytes).

International Space Station

The International Space Station makes some bright passes over the Denver area early in the week.
On Sunday July 20 at 4:05 am the ISS appears in the NW and disappears at 4:11 am in the southeast. (magnitude -2.5)
On Sunday evening at 10:06 pm the ISS appears at 10:06 pm in the west and disappears in the north-northeast at 10:11 pm MDT (magnitude 0.0)
On Monday July 21st it appears at 8:55pm in the west-southwest and disappears in the northwest at 9:00 pm MDT (magnitude -2.2)
On Tue July 22 it appears at 9:18 pm in the west and disappears in the north-northeast at 9:23 pm (magnitude 0.1)
Other passes this week are much dimmer, low and quite brief. Check www.heavens-above.com for times specific to your location.

Sun

On Sunday July 20 sunrise is at 5:51 am and sunset is at 8:27 pm On Saturday July 26 sunrise is at 5:56 am and sunset is at 8:22 pm MDT For more information about the Sun see www.swpc.noaa.gov

Moon

As the week begins, the moon is at lunation 18.
It is in 3rd quarter on Fri July 25 at 12:42 pm.
It ends the week at lunation 24.
Thirty nine years ago this Sunday (July 20, 1969), Neil Armstrong and Buzz Aldrin set foot on the Moon's Sea of Tranquility.

Planets

You may be able to spot the planet Venus just barely above the western horizon around 9pm in constellation Cancer. It is currently magnitude -3.8. Around 9:30 pm you can see Mars and Saturn very low and nearly straight west in the constellation Leo. The semidiameter of Mars is 4.2 arc sec and it is +1.7 magnitude in brightness. Saturn is magnitude +1.2 in brightness and the semidiameter is 16.4 arc sec.

The planet Jupiter may be seen low in the southeast in the constellation Sagittarius as the sky darkens in the early evening. It is magnitude -2.6 in brightness and the semidiameter is 46.9 arc sec. The great red spot crosses the center of Jupiter at the following times this week:

Mon morning July 21 at 1:39 am
Mon evening July 21 at 9:31 pm
Wed morning July 23 at 3:17 am
Wed evening July 23 at 11:09 pm (excellent)
Fri morning July 25 at 3:55 am (low)
Sat morning July 26 at 00:46 am (excellent)
Sat evening July 26 at 8:38 pm (low)

On Monday July 21st, Jupiter's moon Io starts its transit across the disk at 10:55 pm followed by its shadow at 11:14 pm. Transit ends around 01:12 am.

Comets

Here are some comets to locate in the evening sky before the moon rises. C/2008 J1 Boattini is in constellation Cepheus and is magnitude +10.2
C/2007 N3 Lulin is in constellation Sagittarius and is magnitude +11.8?
C/2007 G1 Linear is in constellation Lupus and is magnitude 11.3
C/2007 W1 Boattini is in constellation Aries but the Moon may make it difficult to spot.

Meteor Showers

The annual Perseid meteor shower continues this week. Unfortunately the moon will obscure most of them, though a few of the brighter ones may be visible. The Perseid meteor shower began on July 17, peaks on Aug 12, and continues through Aug 24. Best time to view meteors is in early morning, about two to three hours before sunrise. See www.amsmeteors.org for more info. Also checkout the Astroleague Meteor Club at http://www.astroleague.org/al/obsclubs/meteor/metrcl.html

Summary

This week you can see the International Space Station, take a look at Jupiter's Great Red Spot, view some comets, and maybe some meteors. Join the Longmont Astronomical Society www.longmontastro.org or other astronomy club near you to learn more about the many great objects visible in the night sky.

Some objects to checkup up in the sky, this week May 25 to May 31, 2008

International Space Station

The ISS passes over in the late evening this week. Unfortunately, all passes are low in the NW (more or less) and not bright.

The Sun

There are no active regions currently visible on the Sun's disk.

On Sunday May 25 the Sun rose at 5:39 am and set at 8:20 pm MDT

On Saturday May 31 sunrise is at 5:36 and sunset is at 8:25 pm MDT

The Moon

The Moon will be at 3rd quarter on Thursday May 27 at 8:57 pm MDT

The Planets

Mars is visible in the west after it gets dark about 30 degrees above the horizon in the constellation Cancer. It is magnitude +1.5 in brightness and is 92% illuminated. It now only 5 arc sec in diameter.

Saturn is visible in the west after it is dark as well in the constellation Leo. It is magnitude +1.1 in brightness and is 18 arc sec in diameter.

Jupiter is in constellation Sagittarius and rises around 11:15 pm. It is -2.4 magnitude in brightness and the disk is 45 arc sec in diameter. Jupiter's Great Red Spot (GRS) may be seen about an hour before and after the central crossing which occurs at the following times this week:
Tue May 27 at 01:26 am
Thur May 29 at 03:04 am Sat May 31 04:42 am Sun Jun 1 00:33 am

Comets

Only a couple comets to view this week that are less than magnitude 12. Both will appear nearly stellar and will be difficult to find visually.

C/2006 Q1 (McNaught) is in constellation Antila and is magnitude 10.8 in brightness and the coma is 11.8 arc min in diamter.

C/2007 B2 (Skiff) is in constellation Virgo and is magnitude 12 in brightness and the coma is 1.3 arc min in diameter

Dark Sky

The Moon rises just before 1 am as the week begins and around 3:30 am as the week ends. That must mean its time for some time out in the dark. The Western Nebraska Star Gaze III sponsored by The Panhandle Astronomy Club starts this Thursday near Bridgeport, NE.. Unfortunately, the weather is not looking good at the moment, though that can change.

Some early summertime favorites are now visible in the evening sky. Globulars M13 and M92 are in great position for viewing in the constellation Hercules. Just barely visible for us in the Denver area, only 2 degrees above the southern horizon, is the largest globular cluster visible orbitting our Milky Way Galaxy NGC 5139 or Omega Centauri. Take a look for it this weekend around 10 pm. M3 in Canes Venatici and M5 in Serpens Caput are fine globulars to view as well.

Messier 57, the Ring Nebula, is fairly high up in the sky around midnight in late May in the constellation Lyra. It is one of the summer objects that nearly everyone must check if they have a scope and a clear sky. It is easy to locate about midway between Beta and Gamma Lyrae. M57 is beautiful to look at and is also one of our best examples of a planetary nebula. The star in the center has expelled envelopes of gas and dust and has collapsed to a white dwarf. Intense radiation causes gases surrounding the star to ionize and glow. The ionized oxygen glows a greenish color and the ionized hydrogen a redish color.