Vern’s Weblog

The following is a list of some things to see in the sky this week, July 22 thru July 28, 2007. Some of the events and times given are specific to the Colorado front range (40° N and the MDT timezone).

Highlights

• Comet C/2006 VZ13 is only 40 arc-min away from Messier 3 in Canis Venatici at 10pm MDT this evening (Sunday). If you haven’t found VZ13 yet, here’s your chance! If you can spot it before then, it will be even closer.
• Straight Wall on the Moon can be seen in your telescope tonight (Sunday).
• Great Red Spot and shadow from moon Io in same telescope view on Wed morning July 25 2:42 am

International Space Station
The ISS passes over us early in the morning all week. All passes are short, low in the NNW, not very bright, and won’t be impressive.

Sun
The Sun rises 5:51 to 5:57 am MDT and sets 8:26 to 8:21 pm MDT. No regions are currently visible on the disk. Solar activity is expected to be at very low levels this week.

Moon
Moon was at first quarter, early this morning at 0:29 am MDT. The Moon will transition this week to full phase on July 29. This week is an ideal time to view many lunar features with binoculars or telescope. As the terminator (transition from light to dark) passes near a lunar feature such as a crater, rille, or a dome the rising Sun projects long shadows which makes the details more apparent.

Sun July 22 : Terminator is west (left) of crater Plato, Beer, and Archimedes in the north. Toward the south check out craters Ptolemaeus, Tycho, amd Maginus. Also view the impressive Rupes Recta (the Straight Wall).

Mon July 23: Terminator is west of crater Copernicus near the Moon’s center and craters Longomontanus and Clavius in the south.

Tues July 24: Terminator is west of Sinus Iridium (the Bay of Rainbows) in the north. Locate Promontorium Herculides and Laplace overlooking each side of the bay (see Rukl chart 10).

Wed July 25: Terminator is near crater Aristarchus and Doppelmayer. Explore the Gassendi region for its smaller craters and rilles.

Thurs July 26: Check out crater Shickard and Vallis Schroter.

Fri July 27: The terminator is near craters Grimaldi and Wargentin.

Sat July 28: The Moon is almost full, look for rays and bright albedo features.

Planets

Mercury rises about an hour and a half before sunrise in constellation Gemini. Late in the week look for it around 5am low in the ENE. It is quite bright at -0.4 in magnitude.

Venus sets early at 8:47 pm to 8:28 pm. It will be just barely above the horizon about a half hour after sunset. It is still bright at magnitude -4.3.

Mars rises 1:12 to 1:01 am this week. It moves from constellation Aries into constellation Taurus. Mars is 7 arc-min wide across and +0.55 in magnitude.

Jupiter is straight south in constellation Scorpio around 9:30 pm this week. It sets 2:24 to 2:00 am this week. The Great Red Spot GRS crosses the center of the disk at the following times this week:
Tues July 23 0:04 am
Wed July 25 1:43 am (Io transits at 2:42 am)
Wed July 25 9:34 pm
Fri July 27 11:13 pm
The GRS is visible about an hour before and after the times indicated.

The shadow from Jupiter’s moon Io may be seen crossing the planet’s disk at the following times:
Wed July 25 2:42 am Io starts transit (GRS still visible)
Thur July 26 9:18 pm Io starts transit

Saturn will be difficult to spot very low to the horizon in the WNW a half hour after sunset. It is magnitude +1.1.

Uranus is in constellation Aquarius and is magnitude +5.8.

Neptune is constellation Capricornus and is magnitude +7.8.

Pluto is constellation Sagittarius and is magnitude +13.9.

Asteroids

     Name           Const           RA      Decl       Mag
     1 Ceres        Cetus        03:06:10 +08 30'29"   9.0
     2 Pallas       Pegasus      22:50:11 +09 45'26"   9.5
     4 Vesta        Scorpius     16:08:10 -18 04'05"   6.7
     8 Flora        Cetus        02:45:33 +09 16'58"  10.2
     9 Metis        Ophiuchus    17:34:48 -27 26'19"  10.5
    12 Victoria     Pisces       00:53:47 +17 34'35"  10.5
    15 Eunomia      Auriga       05:17:51 +30 24'37"  10.1
    27 Euterpe      Capricornus  21:38:06 -15 53'14"  10.6
    29 Amphitrite   Aries        03:00:27 +19 59'48"  10.7
    30 Urania       Aquarius     23:10:30 -03 55'52"  10.8
    40 Harmonia     Capricornus  21:01:02 -21 37'34"   9.4
    71 Niobe        Microscopium 20:23:46 -28 42'23"  10.6
    80 Sappho       Aquila       19:56:17 -02 55'43"  10.0
   115 Thyra        Pisces       23:08:19 +02 02'22"  10.8
   194 Prokne       Pegasus      21:51:35 +01 15'16"  10.1
   230 Athamantis   Pegasus      22:39:27 +08 00'26"  10.7
   354 Eleonora     Capricornus  20:12:38 -11 36'20"  10.7
   532 Herculina    Cetus        00:07:07 -17 55'26"  11.0
   980 Anacostia    Sagittarius  19:58:57 -12 34'12"  10.8

Comets

Comet C/2006 VZ13 (Linear) should still be fairly bright around magnitude 9. It moves from constellation Bootes into Coma Berenices.
See http://aerith.net/comet/catalog/2006VZ13/2006VZ13.html for charts and more info. It will pass within about 40 arc-minutes of Messier 3 in Canes Venatici Sunday evening at 10 pm (south of M3 in declination or left of M3 in azimuth).

Comet 29P Schwassmann-Wachman is in constellation Auriga low in the eastern sky just before 5am. It is magnitude +11.9 and has a 1.8 arc-min wide coma.

Dark Sky
Early in the week you can still get some early morning dark sky views as the Moon sets just after midnight.

Meteor showers
If you stay up after midnight, you may see about 4 sporadic meteors per hour (those not associated with any radiant). The sporadic rate increases during July and August. Meteors from the Alpha Capricornids and Delta Aquarids radiants peak at the end of the month (about 1 to 2 per hour each). There may be a few from next month’s Perseids as well. Early in the week will be the best time to avoid moonlight obscuring the dimmer meteors

This entry was posted on Sunday, July 22nd, 2007 at 4:39 pm and is filed under Astronomy. 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.