Vern’s Weblog

The following is a list of some things to see in the sky this week, July 29 thru Aug 4, 2007. Some of the events and times given are specific to the Colorado front range (40° N and the MDT timezone).
Highlights

• International Space Station flies over Wed at 9:41 pm, Thurs 10:04 pm, and Fri 10:27 pm.
• Venus and Saturn disappearing into the sunset glare, last chance to see them for a while
• Comet C/2006 VZ13 (Linear) still visible, last chance this week as well

International Space Station
There are several bright passes of the ISS this week:

Tues July 31 at 04:53:534 am the ISS appears in the NW and disappears at 04:59:28 in the ESE (magnitude -1.4)

Wed Aug 1 at 05:16:44 am appears in WNW and disappears at 05:22:14 in the SSE (magnitude -2.1)
Wed Aug 1 at 9:41:29 10 pm appears in SSW and disappears in the Earth’s shadow at 9:44:01 pm in the SSE (magnitude -2.0)

Thurs Aug 2 at 04:04:36 am appears in NW and disappears at 04:10:02 am in the ESE (magnitude -1.4)
Thurs Aug 2 at 10:04:11 pm appears in WSW and disappears in Earth’s shadow at 10:09:10 pm in the NE (magnitude -1.5)

Fri Aug 3 at 04:30:08 46 am appears in SSW and disappears at 04:32:45 in the SE (magnitude -2.2)
Fri Aug 3 at 8:52:02 pm appears in SSW and disappears at 8:57:34 pm in the ENE (magnitude -1.9)
Fri Aug 3 at 10:27:40 pm in W and disappears at 10:32:21 pm in the NNE (magnitude 0.2)

Sat Aug 4 at 9:14:41 pm WSW and disappears at 9:20:24 pm in the NE (magnitude -1.5)

Sun
The sun rises at 5:58 am to 6:03 am and sets 8:20 pm to 8:14 pm this week. There is one small region, 10965, with 3 spots just east (left) of mid disk today (Sunday). The region will be at mid-disk tomorrow and will rotate around the west limb next Sunday. Solar activity is expected to remain at very low levels.

Moon
The moon is full on Sun July 29 at 6:48 pm. It will be in third quarter next Sat. Aug 5 at 3:20 pm. The following are some interesting features to view around 10:30 pm on the days indicated.

Sun Jul 29 Full Moon, look for rays and albedo features

Mon Jul 30 Craters Langrenus at the eastern edge of Mare Fecunditatis. Look for the twin central peaks and terraced walls. (See http://www.raben.com/weblog/2006/08/11/). Also in Mare Fecunditatis in the southeast, is Petavius. Petavius is a spectacular, complex crater with a fractured floor
terraces, and remarkable rilles.

Tues Jul 31 Mare Crisium, Vallis Rheita, Cleomedes, Endymon, Messier

Wed Aug 1 Cauchy, Taruntius, Atlas, Hercules

Planets

Mercury is low in the ENE about an hour before sunrise early in the week. It moves from constellation Gemini to Cancer and is -1 magnitude.

Venus is still visible but very low straight west and sets 45 minutes after sunset. It is -0.8 in magnitude in constellation Leo.

Mars rises 0:59 am to 0:47 am in constellation Taurus. It is getting closer and grows from 7 to 7.2 arc min across and is magnitude +0.5. The best time to view is just before sunrise when Mars is high up. The following lists the Mars center longitude at 5 am MDT on day indicated. The major features visible at that time this week are Mare Tyrrhenum, Syrtis Major, Hellas, and Mare Serpentis.

Mon July 30 323 deg
Tues July 31 313 deg
Wed Aug 1 303 deg
Thur Aug 2 294 deg
Fri Aug 3 284 deg
Sat Aug 4 274 deg

Jupiter sets 1:56 am to 1:30 am and is straight south in constellation Ophiuchus around 9pm. The Great Red Spot crosses the center of the disk at the following times this week:

Mon July 30 at 0:51 am
Mon July 30 at 8:43 pm
Wed Aug 1 at 10:21 pm

Saturn will be difficult to find low in the west. It is 9 degrees to the right (north) and slightly above Venus. It sets about an hour after sunset and is +1.1 in magnitude.

Uranus is in constellation Aquarius and is magnitude +5.8.

Neptune is constellation Capricornus and is magnitude +7.8.

Pluto is in northwestern part of constellation Sagittarius and is magnitude +13.9.
 

Comets
C/2006 VZ13 (Linear) is magnitude +8.8 and passing through the constellation Virgo. Try for it early in the evening after Wed or Thurs before moonrise. It is in good position this week, but it will be very low by the end of next week. See http://aerith.net/comet/catalog/2006VZ13/2006VZ13.html for charts, etc.

Asteroids

Locations for Aug 3, 2007 at 10:30 pm MDT    

       Name       Const           RA    DECL        Mag
     1 Ceres      Cetus       03:11:48 +08 47'13"   8.9    

     2 Pallas     Pegasus     22:47:22 +09 08'41"   9.4    

     4 Vesta      Scorpius    16:11:33 -18 39'49"   6.8    

     8 Flora      Cetus       02:56:12 +09 48'03"  10.1    

     9 Metis      Ophiuchus   17:32:37 -27 26'58"  10.6    

    12 Victoria   Pisces      00:58:22 +18 18'04"  10.4    

    15 Eunomia    Auriga      05:31:01 +30 31'15"  10.1    

    27 Euterpe    Capricornus 21:32:40 -16 23'53"  10.4    

    29 Amphitrite Aries       03:08:15 +20 46'31"  10.7    

    30 Urania     Aquarius    23:08:43 -03 57'22"  10.7    

    40 Harmonia   Capricornus 20:55:05 -22 15'11"   9.4    

    71 Niobe      Sagittarius 20:16:22 -28 04'10"  10.7    

    80 Sappho     Aquila      19:50:54 -03 13'30"  10.1    

   115 Thyra      Pisces      23:05:51 +02 42'36"  10.7    

   194 Prokne     Aquarius    21:49:03 -00 05'48"   9.9    

   196 Philomela  Capricornus 21:43:45 -23 59'55"  10.9    

   230 Athamantis Pegasus     22:36:26 +08 11'36"  10.6    

   354 Eleonora   Capricornus 20:07:50 -12 23'00"  10.8    

   532 Herculina  Cetus       00:06:14 -18 42'11"  10.9    

   980 Anacostia  Sagittarius 19:52:53 -12 06'40"  10.9

Dark Sky
We can get in some early evening dark sky views this weekend as the Moon rises after 11 pm.

Mars is 1.3666 AU (127 million miles or 204.4 million kilometers) distant and appears to us on Earth as a gibbous disk about 6.8 arc-sec across and 0.58 magnitude in brightness. The next opposition is on Christmas eve of this year when it will be much closer (0.59 AU), -1.6 magnitude in brightness, and 15.8 arc-sec across, or just over double its present size. Central meridian was 38° so its probably Mare Erythraeum and Sinus Meridani which appear as the vague features on the disk. The bluish north polar cap appears as well.

Images taken with Celestron Nexstar11 telescope, Televue 2.5X Powermate, and Phillips 840K webcam, image in approximate NW orientation (north up, east to left). Image aligned and stacked with Registax4. Sky was mostly clear, turbulence around 6/10, transparency very good, 2-3 mph wind, and location was Louisville, CO.
Images taken with Celestron Nexstar11 telescope, Televue 2.5X Powermate, and Phillips 840K webcam, image in approximate NW orientation (north up, east to left). Image aligned and stacked with Registax4. Sky was mostly clear, 68°F, turbulence around 6/10, transparency very good, 2-3 mph wind, and location was Louisville, CO

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

Comet C/2006 VZ13 (Linear) was in great position in the upper part of Bootes when the following image was taken early Sunday morning July 15 at  0:42 to 1:02 am MDT. The core visually does not appear as pin point as it does here, an unfortunate result of brightness enhancement and other processing. Nonetheless it is bright and has a large coma. It was easily seen in my 80mm finder. I tried but wasn’t able to locate it with 7×50 binoculars. The ephemeris shows it to be about magnitude 9.8.

Image acquired with Celestron Nexstar11 telescope, F6.3 focal reducer, and Canon Xti camera at Cassegrain focus. Sky was mostly clear, some high thin clouds (about half of the 30 images were rejected), transparency generally quite good despite the high humidity 70%, dew on everything, temperature about 38°F, and absolutely no wind. Location was near Fox Park, WY. Fox Park is the location for next months Weekend Under the Stars (WUTS) star party. See http://home.bresnan.net/~curranm/wuts.html

Thirty images were acquired but only 15 were usable due to thin clouds. Registax4 and ImagePlus were used to dark subtract, flat field correct, align, and stack (8 of 15) images. Composite with Photoshop Elements2.

The following is a list of some things to see in the sky this week, July 15 thru July 21, 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 (Linear) easily spotted in small scopes
• Sunday July 15 spot the thin crescent Moon low in the WNW
• Monday July 16 the Moon, Saturn, Venus, and Regulus will grouped together after sunset
• Wednesday July 18 both Io transit and the GRS cross the disk 1 to 2 am

International Space Station
There are a number of bright passes this week, all in the early morning. The best ones are:

• Mon Jul 16: magnitude -0.9 rises 04:17:06 in S, disappears in the ENE at 04:20:27 am MDT
• Tues July 17: magnitude -2.5 rises in SW 04:36:08, disappears in the NE at 04:40:32
• Wed July 18: magnitude -1 rises in W at 04:55:06 and disappears 05:00:07 am in NE
• Thur July 19: magnitude -2.0 rises in ENE at 03:42:47 disappears in the NE at 03:45:11 am
• Fri July 20: magnitude -1.2 rises in the WNW at 04:01:35 and disappears in NE at 04:04:44am

Sun
Sunrise is 5:46 to 5:51 am MDT and sunset is 8:31 to 8:37 pm this week. Region 10963 is still quite large and now about midway between center and the west limb (right). It was active for a while but is now decreasing in size. It will rotate over the west limb on Thurs.

Moon
The thin cresecent moon will be beautiful to view in the western sky after sunset early in the week.
Sun July 15 the Moon sets at 9:37 pm so there should be time to spot the thin crescent in WNW.

Mon July 16 the Moon and Saturn will be within 2 degrees of each other after sunset. Venus and star Regulus nearby as well.
Locate Promotorum Agorum in the southeast Mare Crisium

Tues July 17 Mare Crisium, Cleomedes, Langrenus, Vallis Rheita

Wed July 18 Mare Fecunditatis Picard, Petavius Wall,

Thur July 19 Theophilus and Cyrillus, Rupes Altai, Lacus Mortis, Mitchell

Fri July 20 Maurolycus, Vallis Alpes, Appenines, Mons Hadley, Palles Putredinis
Locate the Apollo 11 landing site in the southwest part of Mare Tranquillitatis just south of crater Lamont. July 20 is the 38th anniversary of Apollo 11 landing in 1969.

Sat July 21 Hipparchus, Cassini, Mons Piton, Vallis Alpes

Planets
Venus is low in the west after sunset but still quite bright at -4.4 magnitude. It sets 10:04pm to 9:42 pm this week.

Saturn is low in the west after sunset as well. It is +1.1 magnitude and sets 10:01 pm to 9:43 pm.

Jupiter is magnitude -2.3 in brightness and is straight south at 9:45 pm in constellation Ophiuchus. It sets 2:41 am to 2:20 am.

The Great Red Spot (GRS) crosses the center at the following times:Sun July 15 11:19 pm
Wed July 18 0:46 am
Wed July 18 8:47 pm
Fri July 20 02:35am (Jupiter sets 02:32)
Fri July 20 10:25 pm

The shadow from Jupiter’s moons may be seen crossing the disk at the following times:
Wed July 18 0:54 Io transit starts
Sat July 21 01:50 am Europa transit starts
Sat July 21 21:48 pm Ganymede transit starts

Pluto is in the northern part of constellation Sagitarrius. It is magnitude +13.9 so you’ll need at least a 10 inch scope and accurate charts to locate.

Uranus is in constellation Aquarius and is +5.8 magnitude .

Neptune is in constellation Capricornus and is magnitude +7.8. It rises after 9:42 pm.

Mars is in constellation Aries. It is magnitude +0.6 and rises 1:20 am to 1:10 am this week. Dust storms in the southern hemisphere are reducing the atmospheric opacity and affecting landers and orbiting spacecraft. See http://www.skyandtelescope.com/news/8454732.html
Mercury rises 04:26 am in the northeast in constellation Gemini. It brightens from +1.1 to 0.34 this week.

Comets
C/2006 VZ13 (Linear) moves from constellation Bootes into Canes Venatici. It is magnitude 8.8 in brightness and is easy to spot in a small telescope, 60 mm or larger (if you know where to look). It has a large, bright coma. See http://aerith.net/comet/catalog/2006VZ13/2006VZ13.html for charts, etc.

Asteroids
There are 17 asteroids magnitude +11 or brighter. The locations below are for July 21 at 10:30pm MDT.

        Name               Constellation        RA            Decl        Mag 

  1 Ceres Cetus 02:58:05 +08 04′00″ 9.1

     2 Pallas Pegasus 22:52:58 +10 21′58″ 9.6

  4 Vesta Scorpius 16:05:20 -17 18′09″ 6.5

  8 Flora Cetus 02:30:56 +08 29′12″ 10.3

  9 Metis Ophiuchus 17:39:21 -27 24′16″ 10.3

  12 Victoria Pisces 00:46:15 +16 26′34″ 10.6

  27 Euterpe Capricornus 21:44:22 -15 15′35″ 10.8

  29 Amphitrite Aries 02:49:35 +18 54′41″ 10.8

  40 Harmonia Capricornus 21:08:20 -20 45′42″ 9.7

  71 Niobe Microscopium 20:34:00 -29 26′12″ 10.6

  80 Sappho Aquila 20:03:46 -02 45′20″ 10.1

  192 Nausikaa Sagittarius 18:44:02 -33 11′09″ 10.1

  194 Prokne Pegasus 21:53:47 +02 41′07″ 10.3

  230 Athamantis Pegasus 22:42:02 +07 32′08″ 10.9

  354 Eleonora Capricornus 20:19:07 -10 36′45″ 10.7

  980 Anacostia Capricornus 20:07:20 -13 13′59″ 10.7

 1166 Sakuntala Sagittarius 18:49:28 -24 51′22″ 10.9

Meteor Showers
Sporadic meteor rates (those not associated with any radiant) increase during July and August. In a dark site about 4 per hour can be seen after midnight.
Meteors from the Alpha Capricornids and Delta Aquarids radiants increase mid-July and 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.

Dark Sky Objects
The moon sets before midnight all week so we can still get some dark sky views.

M51 sprial galaxy in Canes Venatici is still high enough for early evening summer views
M101 face on spiral galaxy in Ursa Major is well positioned as well
M64 Blackeye Galaxy in Coma Berenices is bright spiral galaxy with dark lanes
M13 Globular Cluster in Hercules is an amazing sight in a large aperature scope at a dark site.
M16 Eagle Nebula in Serpens
M57 Ring Nebula in Lyra
M4 Globular cluster in Scorpius
M80 globular cluster in Scorpius
NGC 6231 open star cluster in southern Scorpius
M7 naked eye open cluster in Scorpius
M20 Trifid in Sagitarius is a reflection and emission nebula
M8 Lagoon Nebula in Sagittarius is a large, bright emission nebula.
M17 Omega or Swan Nebula in Sagittarius.
M27 Dumbbell Nebula in Vulpecula
NGC 6992 Veil Nebula (east) in Cygnus
IC 5146 Cocoon Nebula in Cygnus
NGC 6826 Blinking Planetary
NGC 6543 Cats Eye Nebula in Draco