Vern’s Weblog

The following is a list of some things to see in the sky this week, Aug 5 thru Aug 11, 2007. Some of the events and times given are specific to the Colorado front range (40° N and the MDT timezone).

Highlights

• Perseid meteor shower late this week and early next (Aug 11 to 15)
• Dark sky weekend!
• The 17th annual Weekend Under the Stars (WUTS) star party near Fox Park, WY this Thursday Aug 9 through Saturday Aug 11

International Space Station

The ISS passes over each night this week, however all passes are low in the NW and not bright.

Sun

The Sun rises 6:04 am to 6:10 am MDT and sets 8:13 am to 8:06 pm MDT. Solar activity is expected remain at very low levels this week.

Moon

The Moon is new on Sun, Aug 12 at 5:02 pm MDT.

Planets

Mercury is getting closer to the Sun this week and won’t be favorably placed until November for us in the northern hemisphere (September for those in the southern hemisphere).

Venus will no longer be visible in the evening sky by the end of the week. It will appear again before dawn towards the end of this month.

Mars rises 0:45 to 0:34 am MDT in constellation Taurus. It is +0.4 magnitude in brightness, 7.4 arc sec across, and 86% illuminated.
Currently, the best time to view Mars is just before sunrise when it is high up (around 5 am). The martian feature Syrtis Major is visible early in the week but rotates from our view midweek. By the weekend the prominent features are Mare Cimmerium, Mare Sirenum, and Olympus Mons. The following are the Mars center longitude at 5 am on days indicated:
Mon Aug 6: 255
Tues Aug 7: 245
Wed Aug 8: 236
Thur Aug 9: 226
Fri Aug 10: 216
Sat Aug 11: 206
Sun Aug 12: 197
(See the annotated Mars map by Damian Peach).

Jupiter is directly south after dark in constellation Ophiuchus.
The Great Red Spot crosses the center of Jupiter at the following times this week.

Mon Aug 6 1:38 am
Mon Aug 6 9:30 pm
Wed Aug 8 11:08 pm
Sat Aug 11 0:47 am
Sat Aug 11 8:38 pm

Saturn sets about a half hour after sunset and is lost in bright twilight. It will reappear in the morning before sunrise in early September.

Uranus is in constellation Aquarius, magnitude 5.7, and 3.6 arc-sec in diameter.

Neptune is in constellation Capricornus, magnitude 7.8, and 2.5 arc-sec in diameter.

Pluto is in constellation Sagitarrius, magnitute 13.7, and 0.1 arc-sec in diamter.

Comets

No reasonably bright comets are in good position this week.

Asteroids

There are 6 asteroids brighter than magnitude +10 this week. Locations are for Sat. Aug 11 at 10:30 pm MDT.

Name Const RA Dec Mag
1 Ceres Cetus 03:18:36 +09 05′07″ 8.9
2 Pallas Pegasus 22:42:45 +08 07′04″ 9.2
4 Vesta Scorpio 16:17:38 -19 28′09″ 6.9
8 Flora Cetus 03:09:51 +10 22′36″ 10.0
40 Harmonia Capricornus 20:47:08 -23 00′16″ 9.6
194 Prokne Aquarius 21:44:50 -02 13′01″ 9.7

Dark Sky

It is dark sky weekend on Aug 10-12! Here are some Messier objects I’m planning on visiting this upcoming weekend.
M4 Globular cluster in Scorpius
M7 naked eye open cluster in Scorpius
M8 Lagoon Nebula in Sagittarius is a large, bright emission nebula
M13 Globular Cluster in Hercules is an amazing sight in a large aperature scope at a dark site
M17 Omega or Swan Nebula in Sagittarius.
M20 Trifid in Sagitarius is a reflection and emission nebula
M22 in Sagittarius is a class 7 globular cluster and magnitude 6 in brightness
M27 Dumbbell Nebula in Vulpecula
M16 Eagle Nebula in Serpens
M54 in Sagittarius is a magnitude 7.5 class 3 globular cluster
M57 Ring Nebula in Lyra
M80 globular cluster in Scorpius

Meteor Showers

The annual Perseid meteor shower should peak around 3:00 am on Aug 13 as the Earth passes through debris from comet Swift-Tuttle. The typical peak rate for the Perseid meteor shower is about 60 per hour. The rate varies through the evening starting with around 50% the peak rate (30 per hour) around 9 pm and increasing to around 90% the peak rate by midnight, to 100% the peak rate by 3 am. The meteor display should be good for a couple days before and after the peak on Aug 13.

This entry was posted on Saturday, August 4th, 2007 at 9:57 pm and is filed under Astronomy, Sky this Week. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.