Vern’s Weblog

Summary of some things to check out in the sky during the week of Feb. 24 to Mar. 1, 2008

Note the planetary diameters are stated in the video as being “arc minutes” across; they should of course be “arc seconds” across!!!

The following is a brief list of some things to see in this sky, this week Feb 17 to Feb 23, 2008.

International Space Station

No bright passes this week.

USA 193

Sun Feb 17 at 5:56:59 appears in the SE and disappears in the ESE at 5:58:24, magnitude 3.8
Mon Feb 18 at 5:49:02 appears in the South and disappears in the ENE at 5:52:17, magnitude 3.1

Iridium 32

Flare at the Eclipse, Feb 20 7:28:22 pm, magnitude -4, essentially straight north (2 deg azimuth), altitude 52 degrees.

MOON

There is a total eclipse of the Moon this week on Wednesday, Feb 24th. The eclipse begins when the pale outer fringe of the Earth’s shadow touches the Moon’s edge at 6:05 PM MST. The shading will be subtle and won’t be very noticeable until the Moon reaches the Earth’s inner shadow at 6:43 PM. From about 7:30 to 8 PM is perhaps when the lunar eclipse will be the most impressive. The curved dark edge of Earth’s shadow will be seen creeping minute by minute across the lunar landscape. The Earth’s shadow will totally engulf the Moon from 8:00 to 8:52 pm MST. After totality ends at 8:52 PM, events unwind in reverse order; the Moon’s edge reappears in sunlight and gradually returns to full at 11:17 PM.

SUN

The Sun rises at 6:53 am on Sun Feb 17th and sets at 5:53 pm for those of us at 40 degrees north latitude. On Saturday, Feb 23rd it rises at 6:45 am and sets at 5:45 pm. There are no active regions visible on the solar disk.

PLANETS

The planet Mercury is visble low in the southwestern sky about an hour before sunrise. It is in constellation Capricornus; it brightens in magnitude from +1 to +0.5 and is 8.4 arc sec across.
The planet Venus is visible to the lower right of Mercury in the constellation Capricornus. It is -3.8 magnitude and 11.5 arc sec across.
Jupiter is visible in the morning sky as well. It is in the constellation Sagitarius and is -1.8 magnitude in brightness and 33.9 arc sec across.
The planet Mars is high overhead in the southwest in the constellation Taurus early in the evening. It is dims this week to magnitude +0.02 and is 9.7 arc sec across.
The planet Saturn is in the constellation Leo. It will be at opposition on Sunday Feb 24th. It is visible in the eastern sky as soon as it is dark. It is +0.56 magnitude in brightness and the disk is 20 arc sec across.

DOUBLE STARS

Our view of dark sky objects such as galaxies and nebulas is restricted during bright moon lit nights. Thats no reason to leave your scope in the basement. You can still observe the planets and double stars. For example, over in the constellation Orion double stars include Beta Orionis or Rigel, Mintaka or Delta Orionis, Iota Orionis, Zeta Orionis or Alnitak and Lambda Orionis or Meisa. Sigma Orionis is a triple system and Theta1 Orionis has 4 components. There are of course, many others. Check the Astroleague Double Star Club for a list of some great double and multiple stars to observe.

Saturn will be at opposition on Feb 24 so now is a good time to photograph the ringed planet. Image below taken last night just after 11 pm.

Sky was clear, turbulence varied between 5 and 6/10, transparency was fair (inversion), temperature around 24°F, location was Gary’s observatory near Niwot, CO using Pete’s scope, a Celestron C11, F6.3 focal reducer, Televue 2.5X Powermate, and DMK 21AF04.AS video camera 1/30 sec shutter, 30fps.

Comet C/2008C1 (Chen-Gao) was passing through a beautiful star field with several small clusters when these images were taken. It showed up quite well through the eyepiece of 14 inch dob. The comet was in Cassiopeae. Estimated brightness is around magnitude 13.

Image was taken at dark sky site we call Roland’s Astro Corral on a private ranch in the Pawnee Grasslands about 40 miles east of Fort Collins, CO with Celestron Nexstar11, F3.3 focal reducer, and Astrovid Stellacam II video camera at 14/14 gain, integrate 128 (4 sec), acquired 40 frames for each image. Temperature was around 25°F, no wind, transparency was excellent, and turbulence was 6/10.

The following is a brief summary of some things to see in the sky this week, Feb 10 to Feb 16, 2008.

International Space Station

Tue Feb 12 at 6:20:28 pm the ISS appears in the NNW and disappears in the NE at 6:23:25 pm (-0.4 magnitude)
Wed Feb 13 at 6:40:29 pm the ISS appears in the NW and disappears in the NE at 6:43:32 pm (-1.4 magnitude)
Thurs Feb 14 at 7:00:44 pm the ISS appears in the NW and disappears in the SE at 7:03:45 pm (magnitude -2.5))
Fri Feb 15 two passes at 5:46:25 pm it appears in the NNW and disappears in the east at 5:51:25 pm (magnitude -1.3)
and at 7:21:27 pm it appears in the WNW and disappears in the SSW at 7:24:070 (magnitude -0.3)
Sat Feb 16 at 6:06:31 it appears in the NW at 6:06:31 pm and disappears in the SE at 6:12:08 (magnitude -2.5)

Sun
For us at 40 degrees north, the sunrises Sunday morning at 7:01 am and sets 5:32 pm. Next Saturday it rises at 6:54 am and sets at 5:39 pm. No regions are currently visible on the Sun’s disk.

Moon
Sun Feb 10 lunation 4 days: Craters Atlas, Hercules, Macrobius and Taruntius
Mon Feb 11 lunation 5 days: Craters Posidonius, Theophilus, and Picollomini. Luna Mara Tranquillatis
Tue Feb 12 lunation 6 days: Crater Aristoteles, Eudoxus, and Maurolycus
Wed Feb 13 lunation 7 days: in first quarter at 8:34 pm mst: Craters Casini, Aristillus, Hipparchus, Albategenius, and Werner. Check out the Montes Alpes and Montes Caucasus.
Thur Feb 14 lunation 8 days: Crater Plato, Archimedes, Alphonsus, Arzachel, and Tycho. Observe Rupes Recta, the straight wall.
Fri Feb 15 lunation 9 days: Craters Copernicus, Bulliardus, Fra Mauro, and Longomontanus.
Sat Feb 16 lunation 10 days: Check out Sinus Iridium, “the Bay of Rainbows” and Montes Jura.

Planets
Mars is up high in constellation Taurus in the early evening. By Saturday it will be 10.3 arc sec and -0.16 magnitude in brightness.
Saturn is in constellation Leo and is visible in the eastern sky as soon as its dark. It is 0.6 magnitude in brightness and the disk is 20 sec across. By 9 pm is it in good position for viewing and imaging.
Jupiter is in constellation Sagittarius and is visible in the eastern sky before sunrise. It is magnitude -1.77 in brightness and 33 arc sec across.
Venus is sinking lower each day. It is just barely visible above the southeastern horizon as the sky brightens before sunrise. It is -3.8 magnitude in brightness and 11.8 arc sec across.

Dark Sky
The moon interfers with our evening dark sky views this week.
Comets
17P Holmes is in constellation Perseus. It is currently 1.5 degrees or so across. It is still easy to spot in binoculars at a dark sky location.
46P Wirtanen is in constellation Aries and is magnitude 9.2 in brightness
29P Schwasmann-Wachmann is in constellation Auriga and is magnitude 11.4 in brightness
C/2008 C1 (Chen-Gao) is in constellation Cassiopeia and is magntiude 12.7 in brightness