Vern’s Weblog

Highlights

Early October is a great time for observing the heavens especially here in Colorado.  The mosquitoes are gone, the nights are long and cool, but not yet too cold.  There are many great objects to observe. We can still see many of the summer favorites in the early evening, all the fall and winter objects, and even a few early spring ones if we can stay awake until dawn.

• Bright passes of the ISS on Tues 8:15 pm, Thurs 7:30 pm, Fri 7:53 pm and Sat 8:13 pm MDT
• The comet (C/2007 F1 Loneos) in constellation Coma Berenices brightens from magnitude 10 to 9 this week.

International Space Station

There are a number of bright ISS passes this week which are visible in the early evening:

Tues. Oct 2 the ISS rises in the SSW at 8:14:30 pm MDT and disappears in the SSW at 8:15:34 pm (magnitude -0.3)
Thurs. Oct 4 the ISS rises in the SSW at 7:26:07 pm MDT and disappears in the ENE at 7:30:31 pm (magnitude -1.7)
Fri. Oct 5 the ISS rises in the WSW at 7:49:13 pm MDT and disappears in the NE at 7:53:25 pm (magnitude -2.0)
Sat. Oct 6 the ISS rises in the W at 8:13:07 pm MDT and disappears in the N at 8:16:08 pm (magnitude -0.2)

Sun

This week the Sun rises at 6:57 am to 7:03 am MDT and sets 6:48 pm to 6:38 pm MDT.  Only one small region, 10971 is visible today (Sunday). It is located west (right) of the center of the Sun’s disk.  See solar map at http://raben.com/maps . Solar activity is expected to remain at very low levels this week.

Moon

The Moon transitions to third quarter on Wed. Oct. 3rd at 4:06 am MDT.

Planets

Mercury still very low in the SW  early in the week and sets about a 45 minutes after sunset. It is getting dimmer, the magnitude is +0.3 and 7.6 arc sec in diameter.

Venus shines brilliantly at magnitude -4.4 before sunrise, high up in constellation Leo; it rises around 3:30 am.  It appears in a telescope as a thin crescent.

Mars rises shortly before 11 pm MDT in constellation Gemini.  By Saturday it will -0.15 magnitude in brightness, 10.1 arc sec across, and 87% illuminated. The best time to view Mars is when it is high up after 3 am.  Early in the week the martian features the features Mare Erythraeum, Vallis Marinerius, and Solis Lacus are in our view around that time.   Later in the week  Solis Locus, Olympus Mons, Mare Sirenum, and Mare Cimmerium are visible. See Sky and Telescope’s Mars profiler for other times and additional information.  By Saturday there will only be 79 more days till opposition on Christmas eve!

Jupiter is the brightest object in the SW  after sunset at magnitude -1.8.  For us in the Denver area, its down low in the turbulence over the mountains so its tough to see much detail other than a band or two. It sets before 10 pm. Jupiter’s Great Red Spot  crosses the center of the disk at the following times: (it is visible about an hour before and after the central meridian crossing).

Sept. 30 at 10:08 pm
Oct. 3 at 7:39 pm
Oct 5 at 9:18 pm

Saturn rises low in the ENE just before 4 am is located just below and left of star Regulus in constellation Leo. It is magnitude +1.1 in brightness.

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.

Dark Sky

The Moon rises after midnight after Wednesday and not till after 2 am by Saturday so we can get some time in the dark late this week.

Galaxies
M31 (mag 3.4), M32 (mag 8.1), M110 in Andromeda
M33 in Triangulum (mag 5.7)
NGC 7331 in Pegasus (mag 9.5)
Near NGC 7331 is Stephan’s quintet in Pegasus. You’ll need at 10 inch or larger scope to see them all. The quintet of galaxies is NGC 7317 (mag 14.7), 7318A (mag 14.3), 7318B (mag 14),  7319 (mag 14.2),  & 7320 (mag 13.3).
NGC 7479 (mag 11)

Nebula
The ‘Ring Nebula’ M57 (mag 8.8) in Lyra
The ‘Snow Globe Nebula’, NGC 6781 in Aquila (mag 11.4)
NGC 6804 (mag 12) in Aquila
The ‘Blinking Planetary’, NGC 6826 in Cygnus
The ‘Dumbbel Nebula’, M27 (mag 7.3)  in Vulpecula
NGC 6894  (mag 12.3) in Cygnus
The ‘Helix Nebula’, NGC 7293 in Aquarius
The ‘Blue Snowball’, NGC 7354 in Cygnus

Globular Clusters
M2 in Aquarius (class 2)
M15 (mag 7.3) in Pegasus
NGC 6981 (mag 9.2) in Aquarius
M30 (mag 6.9) in Capricornus

Meteor Showers

Activity picks up this month a bit compared to September. Early in the evening expect to see about 4 per hour and about 15 per hour around 5 am. Sporadic rates (meteors not associated with a particular radiant) peak this month.  There are active radiants such as the Taurids, Draconids, Delta Aurigids which provide 1 or 2 per hour each. The Draconids peak on Oct 9 and the Orionids meteor shower peak on Oct 21. The Moon interferes during the best to time to observe meteors which is an hour or two before dawn. The weekend (Oct 11-12) will be an ideal time for watching meteors.

Asteroids

Here is a list of asteroids brighter than magnitude +11, positions are for Oct 6 at 10:30 pm.

     Name      Const      RA        DEC     Mag
   1 Ceres       CET   03:32:34 +09 00′43″  7.9
   2 Pallas      AQR   22:06:45 -02 58′41″  9.3
   6 Hebe        HYA   08:44:00 +10 53′34″ 10.6
   8 Flora       TAU   04:09:36 +10 49′35″  8.9
  10 Hygiea      PSC   00:25:43 +08 42′43″ 10.2
  12 Victoria    AND   00:40:21 +15 56′36″  9.3
  13 Egeria      PSC   01:30:30 -03 22′14″ 10.3
  15 Eunomia     GEM   07:28:12 +28 13′43″  9.8
  29 Amphitrite  TAU   03:51:32 +26 58′04″  9.6
  30 Urania      AQR   22:22:26 -07 30′19″ 10.6
  40 Harmonia    CAP   20:35:16 -23 37′44″ 10.9

Comets

Comet C/2007 F1 (Loneos) is visible at magnitude 10 and will brighten to magnitude 9 this week. It may become as bright as magnitude +4 next week.  It is in constellation Coma Berenices and maybe found very low in the northeast before dawn, the best time is around 5:30 am. The comet is far enough north that it is visible in the northwest after sunset as well, it sets around 8:20 pm.  For more information, finder charts etc, see http://www.cometchasing.skyhound.com/ . It passes near the Coma Berenices cluster early Saturday morning. Around 5 am it is within 16 arc minutes of the 5th magnitude star 14 Berenices and 27 arc minutes from the 5th magnitude star 16 Berenices.

Fall has arrived, the autumn equinox occurred at 4:37 am MDT this morning. Our nights are getting longer, the Sun rises before 7 am and sets before 7 pm as well. It is fairly dark around 8. If we look to the east we can see that the great square of Pegasus is already high up and the stars in the northern cross of Cygnus are overhead. The Moon interferes with our views of the night sky this week. That is no excuse though, to not to get your scope out of the garage. The Moon is a wonderful object to explore. I’d suggest starting your exploration of the Moon by locating the targets listed in the Astroleague’s Lunar Club program. For those more advanced, the Astroleague Lunar II program is challenge that only 3 people have accomplished.

International Space Station
There are a number of good ISS passes this week but all are in the early morning. Here is a list of the brightest ones:

Sept. 25 the ISS rises in the NW at 5:48:59 am and disappears in the ESE at 5:54:24 am (magnitude -1.1)
Sept. 26 the ISS rises in the WNW at 6:10:42 am and disappears in the SE at 6:16:19 am (magnitude -2.3)
Sept. 27 the ISS rises in the ENE at 5:00:43 am and disappears in the ESE at 5:02:56 am (magnitude -0.7)
Sept. 28 the ISS rises in the SSE at 5:22:32 am and disappears in the SE at 5:24:52 am (magnitude -2.0)
Sept. 29 the ISS rises in the SSW at 5:44:31 am and disappears in the S at 5:45:43 am (magnitude -0.4)

Sun

This week the Sun rises at 6:51 am to 6:57 am MDT and sets 6:59 pm to 6:49 pm MDT. No regions are visible today (Sunday), in fact none have been visible since Sept. 4. Solar activity is expected to remain at very low levels this week.

Moon

The Moon is full on Wed. Sept 26 at 1:45 pm MDT. Since it occurs close to the autumn equinox, it is called a “Harvest Moon”. The following are some Lunar II Club targets for this week:

Sun Sept 23: Mons Rumker, Wargentin
Mon Sept 24: Bailly, Cruger, Grimaldi Basin, and Rima Cauchy
Tues Sept 25:
Wed Sept 26:
Thurs Sept 27: Mare Undarum, Montes Corillera, Mare Spumans
Fri Sept 28: Messier, Vallis Rheita
Sat Sept 29: Sinus Concordiae, Taruntius

Planets

Mercury appears very low in the SW early in the week and sets about a 50 minutes after sunset, magnitude -0.0 and 6.2 arc sec in diameter. It is at its greatest elongation on Saturday but sets earlier (7:38 pm) and will be very difficult to locate.

Venus shines brilliantly at magnitude -2.8 before sunrise, high up in constellation Leo; it rises around 3:30 am. It appears in a telescope as a thin crescent.

Mars rises shortly after 11 pm MDT and moves to constellation Gemini this week. By Saturday it will -0.1 magnitude in brightness, 9.7 arc sec across, and 87% illuminated.
Best time to view Mars is when it is high up after 3 am. Early in the week the martian features the features Solis Locus, Olympus Mons, Mare Sirenum, and Mare Cimmerium are in our view around that time. Later in the week are Mare Erythraeum, Vallis Marinerius, and Solis Lacus. See Sky and Telescope’s Mars profiler for other times and additional information. By Saturday there will only be 88 more days till opposition on Christmas eve!

Jupiter is the brightest object in the SW after dark in constellation Ophiuchus. For us in the Denver area, its down low in the turbulence over the mountains so its tough to see much detail other than a band or two. It sets before 10:30pm. Jupiter’s Great Red Spot crosses the center of the disk at the following times:

Sept. 23 at 9:19 pm
Sept. 26 at 6:50 pm
Sept. 28 at 8:29 pm

Saturn rises low in the ENE around 4 am just below and left of star Regulus in constellation Leo and is magnitude +1 in brightness.

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.

Dark Sky

Not this week!

The following is a list of some astronomical objects and events to watch this week, Sept. 16 thru Sept. 22, 2007. Some of the events and times given are specific to the Colorado front range (40° N and the MDT timezone).

Highlights

• Timothy Ferris film “Seeing in the Dark” airs on PBS Wed. Sept 19 at 7:00 PM for us in the Denver area, and at 8:00 PM in most locations. Check your local pbs listings in your area.
• This week is an excellent time to view craters, domes, rilles, and other lunar features

International Space Station
There are 4 visible passes this week but none are very bright. All are low in the NNE, and early in the morning around 4:30 to 6 am.

Sun

This week the Sun rises at 6:44 am to 6:50 am MDT and sets 7:11 pm to 7:01 pm MDT. No regions are visible today (Sunday). Solar activity is expected to remain at very low levels this week.

Moon

The Moon is in first quarter on Wed. Sept 19 at 10:48 am. The following are some Lunar II Club targets for this week:
Sun Sept 16 the moon sets 9:16 pm, lunation 5.7: Arago, Baco, Cauchy, Censorinus, Dorsa Lister, Posionius, and Dorsa Smirnov, Lacus Mortis, Lamont, Rabbi Levi, Rima Janssen, Ritter and Sabine, Sinus Asperitatis
Mon Sept 17: sets 9:53 pm, lunation 6.7 craters Hercules, Julius Caesar, Linne, Sacrobosco and Rima Ariadaeus
Tues Sept 18: sets 10:38 pm, lunation 7.7 Alpetragius, Cassini, Muller, Regiomontanus, Rima Hadley, Triesnecker, Sinus Lunicus, Thebit, and Vallis Alpes
Wed Sept 19: sets 11:33 pm, lunation 8.7 Beer, Feuillee, Clavius, Hesiodus A, Sinus Amoris, Stadius, Timocharis, and Wolf
Thur Sep 20 sets after midnight 21st at 0:23, lunation 9.7: Buillialus, Hrotensius dome field, Kies, Mare Cognitum, Mare Insularum, and Sinus Aestuum, Montes Recti, Teneriffe, and Spitzenbergen, Rima Hesiodus and Hippalus
Fri Sep 21 sets after midnight 22nd at 1:41 am, lunation 10.7: Hainzel, Dome Milichius PI, Mons Gruituisen, Montes Focault and Jura.
Sat Sep 22 sets after midnight on 23rd at 2:53 am, lunation 11.7: Aristarchus Plateau, Mairan, Marius Hills, Mersenius, Montes Agricola, Schiller, Segner, and Zucchius

Planets

Mercury appears very low in the WSW and sets about an hour after sunset, magnitude -0.1 and 5.7 arc sec in diameter

Venus is visible in the early morning in constellation Cancer. It rises around 4 am and is quite bright at magnitude -2.

Mars rises 11:29 pm to 11:18 pm MDT in constellation Taurus. By the end of the week it will +0.0 magnitude in brightness, 9.2 arc sec across, and 86% illuminated.
Best time to view Mars is when it is high up (around 4 to 6 am). The martian features Mare Cimmerium, Mare Tyrrhenum, and Syrtis Major are visible early in the week at that time. Later in the week the features Olympus Mons, Mare Sirenum, and Mare Cimmerium are in our view. See Sky and Telescope’s Mars profiler for other times and additional information.

Jupiter is in the SSW after dark in constellation Ophiuchus. Jupiter’s Great Red Spot crosses the center of the disk at the following times:
Sept. 16 at 08:31 pm
Sept. 18 at 10:10 pm
Sept. 21 at 07:40 pm
Sept. 23 at 09:19 pm

Jupiter is setting around 10:30 pm now so our views of it are limited, especially against the unstable air over the mountains to our west (from here in the front range in Colorado). Best time to look is during early twilight, shortly after sunset, when it is still high up.

Saturn rises very low in the ENE around 4:40 am just below and left of star Regulus in constellation Leo.

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 14, and 0.1 arc-sec in diameter.

Comets

Comet 29P/Schwassmann-Wachmann is in constellation Auriga and is magnitude 11.7 in brightness with a 2 arc-min coma. See finder chart on the Skyhound comet page.

Asteroids

There are 16 asteroids brighter than magnitude +11 this week. Locations below are for Sat. Sept. 22 at 10:30 pm MDT.

Name Const RA DEC Mag
1 Ceres CET 03:35:49 +09 20′03″ 8.2
2 Pallas AQR 22:13:09 -00 06′02″ 9.1
6 Hebe CNC 08:22:04 +11 56′27″ 10.6
8 Flora ARI 04:02:55 +11 13′53″ 9.2
10 Hygiea PSC 00:36:00 +09 46′30″ 10.3
12 Victoria AND 00:52:26 +18 10′32″ 9.5
13 Egeria PSC 01:43:34 -03 03′10″ 10.6
15 Eunomia AUR 07:07:34 +29 06′47″ 9.9
29 Amphitrite ARI 03:50:50 +25 58′21″ 9.9
30 Urania AQR 22:29:33 -06 52′44″ 10.2
115 Thyra PEG 22:19:06 +04 23′54″ 10.1
185 Eunike CET 23:58:37 -16 53′24″ 10.8
194 Prokne AQR 21:30:06 -14 16′14″ 10.4
230 Athamantis AQR 21:58:18 +04 11′45″ 10.4
349 Dembowska AUR 04:50:32 +26 02′30″ 10.6
511 Davida CET 02:25:56 -10 04′20″ 10.7

Dark Sky

Still some dark sky early in the week if you can get up early in the morning.

Meteor Showers

No major showers are currently visible, however the sporadic meteor rates are higher this time of year, around 3 might be seen per hour after dark and 14 per hour around 4 am. Visit the American Meteor Society for more information.

The image below is of a faint globular cluster in Sagittarius called Terzan 11. Dark area surrounding cluster is probably caused by obscurring dust which extinguishes light from an area that is rich with Milky Way stars (compare to star field on the left). The globular is listed as magnitude 16.4 so it is a tough object even for large aperature scopes. Tough to guess the classification as it so faint. Location was confirmed with DSS POSS2 image. I should have posted this before but I mis-filed the images and didn’t come across them until this afternoon.

Images were taken at Fox Park in Wyoming on July 15, 2007 at 03:35 am MDT with a Celestron Nexstar 11 telescope, F3.3 focal reducer, and Stellacam II video Camera. Stellacam set at 14/14 gain, medium gamma, and 256 frame integration (8 sec). Registax4 used to dark subtract, flat field correct, align, stack, end brightness enhance 30 frames.

Sky was mostly clear, some high thin clouds, transparency generally quite good despite the high humidity 70%, dew on everything, temperature about 38°F, and no wind.

Located in constellation Cygnus at RA 21° 14′ 09″ and Dec +47° 46′ 24″ is a faint (vmag 14.5), oblong-shaped planetary nebula known as the “Moth Nebula”. I only picked up the middle part of the “moth” with the Stellacam which may be seen at the center in the image below.  The Stsci Digitized Sky Survey image shows faint “wings” extending to the upper left and to the lower right.

Image above taken from “Cactus Flats North” in the Pawnee National Grasslands near Briggsdale, CO on Saturday morning, Sept. 8, 2007 around 2:33 am MDT. Celestron Nexstar 11 telescope with F3.3 focal reducer and Stellacam II video camera used to capture 30 images. Camera set at full gain (14/14), medium gamma, and 256 frame integration (8 sec).  Registax4 used to flat field adjust, dark frame subtract, align, and stack images. Cropped and brightness enhanced with PhotoShop Elements 2.

Sky was clear, 2-3 mph wind, transparency very good, turbulence about 6/10, temperature 51°.F.