Vern’s Weblog

On a clear, dark, summer night I always love taking a look at the great globular cluster Messier 13 when its high overhead. It looks good in small scopes, but the view in a large scope such as my friend Gary’s 30″ dob is stunning. So many worlds, hundreds of thousands of suns in close orbits. Their skies must be filled with bright stars — maybe so many and so bright that their view of the universe is limited.

Image taken around 1 am Sunday morning May 27, 2007 from Louisville, CO with a Celestron Nexstar11 telescope, a F6.3 focal reducer, and a Canon Xti camera. Camera was set to ISO 800 and a 30 second exposure. Registax4 was used to align, stack, and enhance brightness. Sky was mostly clear, temperature 58° F, turbulence between 5 and 6/10, no wind, and transparency was quite good.

Messier 57, the Ring Nebula, is fairly high up in the sky around midnight in late May. It is one of the summer objects that nearly everyone takes a look at if they have a scope and a clear sky. M57 is beautiful to look at and is also one of our best examples of a planetary nebula. The star in the center has expelled envelopes of gas and dust and has collapsed to a white dwarf. Intense radiation causes gases surrounding the star to ionize and glow. The ionized oxygen glows a greenish color and the ionized hydrogen a redish color.

The image above was taken early Sunday morning May 27, 2007, with a Celestron Nexstar11 telescope, a F6.3 focal reducer, and a Canon Xti camera. Camera was set to ISO 800 and a 25 second exposure. Registax4 was used to align and stack 16 images. Sky was mostly clear, temperature 58° F, turbulence between 5 and 6/10, and no wind. Transparency was quite good although the humidity was high and dew was on about everything. Location was Louisville, CO.

Here is above M57 in desktop wallpaper or screen saver size (1280×1024). Send me a note if you would like another size.

The following is a list of some interesting things to see up in the sky this week, May 27 thru June 2, 2007. Some of the events and times given are specific to the Colorado front range (40° N and the MDT timezone).

International Space Station

All ISS passes this week are low in the north, only magnitude +2 or 3 in brightness, a few seconds in duration, and early in the morning.

Sun

Sunrise is 5:38 am to 5:35 am MDT this week. Sunset is 8:21 pm to 8:25 pm MDT. Not much activity on the Sun lately, there are no regions visible. Solar activity is expected to remain at very low levels this week.

Moon

The Moon is full on Thurs. May 31 at 7:04 pm MDT. The following features should have good contrast for viewing on the days indicated:

Sun May 27 Doppelmayer, Encke, Gassendi, Montes Jura, J. Herschel, Hippalus
Mon May 28 Aristarchus, Vallis Shroteri, Billy, Schickard, Reiner Gamma
Tue May 29 Grimaldi, Wargentin
Wed May 30
Fri May 31 Full moon, look for rays!
Sat Jun 1 Promotorium Agarum

Planets

Mercury moves from constellation Taurus into Gemini this week. Its visible in the WNW after sunset at magnitude +0.5 and has a 7.1 arc sec wide disk.
Venus is in constellation Gemini magnitude and -4.1 magnitude brightness and 20.7 arc sec wide. It is visible in the WNW after sunset.
Saturn is in constellation Leo and is +0.5 magnitude and has a 17.6 arc sec disk. It is high up in the WSW after sunset.
Jupiter is in constellation Ophiuchus and rises before 9 pm in the SE. It is magnitude -2.6 and is currently 45.6 arc sec across.

The Great Red Spot (GRS) crosses the center at the following times this week:
Mon May 28 at 3:47 am
Mon May 28 at 11:38 pm
Wed May 30 at 5:25 am
Thurs May 31 at 1:16 am
Thurs May 31 at 9:07 pm
Sat Jun 2 at 2:54 am
Sat Jun 2 at 10:45 pm
The GRS is visible about an hour before and after the central meridian crossing.

Pluto is in constellation Sagitarius and is magnitude +13.9
Neptune is in constellation Capricornus and is magnitude +7.9 and 2.5 arc sec across
Uranus is in constellation Aquarius at magnitude +5.9 and 3.4 arc sec across.
Mars is in constellation Pisces. It is magnitude 0.8 and 5.8 arc sec across.

Comets
96P Machholz is moving rapidly from constellation Delphinius to Aquila. It is currently magnitude +12.9. (See image from Cactus Flats N. last week at http://www.raben.com/weblog/2007/05/23 )
C/2007 E2 (Lovejoy) is in constellation Draco. It is currently magnitude 11.1 and has a 3.4 arc-min wide coma (See http://www.raben.com/weblog/2007/04/30/)
C/2006 VZ13 (LINEAR) is in constellation Andromeda. Magnitude 13.5, getting brighter will be magnitude 9 by July. (See image from Cactus Flats N. last week at http://www.raben.com/weblog/2007/05/22 )

Asteroids
There are eight asteroids visible this week brighter than magnitude +11. Four may be seen early in the evening. Position and magnitude are for Fri June 1 at 10:30 pm MDT. Consult your star chart program for asteroid position on different days.

3 Juno is in constellation Virgo (RA 12:59:58, Dec +04 26′54″) magnitude +10.6
4 Vesta is in constellation Ophiuchus (RA 16:30:33 Dec -14 08′43″) magnitude +5.4
85 Io is in constellation Ophiuchus (RA 17:19:44, Dec -06 42′50″) magnitude +10.8
21 Lutetia is in constellation Ophiuchus at RA 16:28:50 Decl -20 43′37″ magnitude +9.9
9 Metis is in constellation Sagittarius at RA 18:27:12 Decl -25 58′25″ magnitude +10.2
192 Nausikaa is in constellation Sagittarius at RA 19:30:55 Decl -32 07′02″ magnitude +10.8
2 Pallas is in constellation Pegasus at RA 22:45:06 Decl +10 04′48″ magnitude +10.3
40 Harmonia is in constellation Capricornus at RA 21:15:48 Decl -17 45′05″ magnitude +10.9

Dark Sky
The moon interferes with our views of the dark sky this week.

The moon last evening at lunation 10.43, 11:50 pm MDT. The skies didn’t look promising last evening, it was mostly cloudy and light rain fell around 9. However, the skies cleared around 10:30 pm so I set up the scope to take a look at Sinus Iridium (the crescent shape near the left top in the below photo). Actually Sinus Iridium or the “Bay of Rainbows” is half of a 162 mile (260 km) wide impact crater whose southeastern side has disappeared.

Image taken with Celestron Nexstar11 telescope, F6.3 focal reducer, and Canon Xti camera (ISO 400, 1/500 sec shutter). Sky was mostly clear, temperature 58° F, turbulence between 5 and 6/10, no wind, transparency quite good, but dew and high humidity. Location was Louisville, CO. Images aligned and stacked with Registax4 (17/40 images, wavelet filters (12,8,1,1,1,1). Cropped, enhanced, unsharped mask with Photoshop Elements2.

And here is a view of Sinus Iridium through the Phillips Toucam at cassegrain focus on the Nexstar11.

Here  is another image of comet 96P Machholz from last Sunday morning between 2:45 am and 3:20 am.  It is getting less bright each day, currently about magnitude +12.5 to +13.  Its moving quite fast so its difficult to stack.  NGC 7003 was in the same field at the time the images were taken.

Image taken with Celestron Nexstar11 telescope, F3.3 focal reducer, and Stellacam II video camera.  Location was Cactus Flats North, 7 miles east of Briggsdale, CO.  Temperature was  46°F, no wind, sky was clear, and turbulence about 6/10. Transparency was good although humidity was high — dew everywhere. Registax4 used dark subtact, flat field correct, align, and stack approximately 4 minutes of video. Stellacam set to 10/14 gain, 256 integration (8 sec), and medium gamma.