Sent: Friday, February 23, 2007
Subject: Observing Note Omission 2007 Feb. 22 UT
Hi Guys,
My “Observing Note for 2007 Feb. 22 UT” had an omission. Let me add
4.A. MESSIER 50 in Monoceros, an open star cluster, was seen by me for the first time using the 635mm Obsession at 84x and the 120mm refractor at 20x.This is a rather loose cluster seen against a fairly rich Milky Way starry background. In the larger telescope the background tended to distract from the foreground star cluster; in the refractor M50 was better seen as a whole. There is value in having both larger and smaller in exploring the deep sky!
Sent: Thursday, February 22, 2007 12:16 AM
Subject: Observing Notes – 2007 Feb. 22 UTObservations at Hodgson Observatory conducted by Dick Hodgson working alone.
2007 Feb. 22, 01h 32m to 03h 11m UT Seeing fair, ~ 5-6/10;
Transparency fair due to bright crescent Moon on snow ~ 5.0 limiting magnitude.
Temperature +2 C. (36 F) falling to + 1 C. (34 F).
Wind moderate ~ 5 to 10 > m.p.h. from west.
Sky Clear of Clouds but a little hazy near horizon.OBSERVING LIST follows in order and with brief descriptions: 1. SIRIUS in Canis Major, initial check star, seen with 120mm refractor (20x > with 50mm Orion Optilux eyepiece all evening). 2. MESSIER 79 in Lepus. Very good view of this globular cluster. Primarily used 635 mm Obsession Newtonian (84x, 124x). Some of the outermost stars were resolved. Also good in 120mm refractor at 20x.3. SATURN with three satellites, from 02h 05m to 02h 35m UT. Tried 84x, 124x, and 201x but the seeing was not nearly as good as last night; image detail was degraded compared to the clarity of last night. The wind rose to ~ 10 m.p.h. briefly at this time; quite possibly a weak weather front was passing through the area.
QUICK VIEWS: Because of the moonlight I thought it best to focus on stars or open clusters rather than galaxies that easily “wash out.”
4. First quick target was Variable star R LEPORIS, with both 635mm (at 84x) and 120mm telescopes, distinctly red but not as deep red as a month ago.
5. M41, open cluster in Canis Major, was beautiful in both telescopes.
6. Then on to M67, a very old open cluster in Cancer with 120mm refractor. Its stars are fainter but well seen in the 120mm refractor in spite of moonlight.7. This was followed by M44, Praesepe also called the Beehive Cluster, a beautiful, brighter (and much nearer) open cluster almost as impressive as the Pleiades in Taurus, viewed with the 120mm telescope.8. M48, an open star cluster in Hydra, then followed — the 120mm refractor gave an excellent view. 9. Then I turned to the bright star Regulus in Leo for the first time in six months and observed it with both telescopes.
10. The evening closed a test to see if I could see a moderately bright galaxy, NGC 2903 in the head of Leo with the 120mm refractor at 20x. I really expected that due to moonlight it would be invisible or barely visible, but it was easily seen and its spiral shape was evident. I did not try looking at it in the 635mm Obsession — I was about to close down. Perhaps I should have, but I think a high power inspection of this galaxy,
a favorite of mine since the early 1970′s, deserves a darker night to be worthwhile. I ceased observing with the 120mm refractor at 03h 11m UT.
In summary, while the Saturn view was disappointing, the stars and especially the star clusters were fairly good, their images only a little spread. Seeing, however, was only fair so it was not a night for really good high power views. Dew was not a problem at all. If there were no Moon present I would have observed longer.
Sent: Wednesday, February 21, 2007 12:06 PM
Subject: Saturn’s Satellite ID for Feb. 21 UTHi Guys,Just a quick identification of Saturn’s satellites observed last night (Feb. 21 UT):
I have checked with the Astronomical Almanac this morning. As suspected the satellites seen were Titan, Rhea, Dione and Tethys, from brightest and outermost to innermost and faintest. They are a nice series of tests. The fifth object seen only very briefly was not Enceladus which was elsewherein its orbit, but may well have been Mimas which was at that location in its tiny orbit at the time! I have not seen very faint Mimas since the 1980′s with my 410mm (16-inch) Newtonian in the mid-1970′s. (Mimas orbit lies inside of that of Enceladus, and just outside the rings.)
Sent: Tuesday, February 20, 2007 10:44 PM
Subject: Southern Deep Sky Observing
2007 Feb. 21, 01 h 35m to 02h 20m UT (Feb. 20, 7:35 to 8:20 p.m. CST) using the 635mm (25-inch) Obsession reflector & the 120mm f/8.3 refractor.
INTRODUCTION. Here is a brief observing report from Hodgson Observatory of tonight’s viewing. RG Hodgson observed alone. A crescent Moon in the west on largely snow-covered ground negatively impacted any galaxy searches; some thin diffuse cloud began to cover the western & southern sky after about half an hour’s viewing.
Seeing was good ~ 8 on a 10 scale, due to Moon etc.
Transparency was ~ 5 magnitude at best.
Wind was very light (~ 2 to 3 m.p.h.?) out of the south;
Temperature 32 degrees F. (0 C.) throughout.
Initially at 1h 35m SIRIUS the Dog Star in Canis Major was briefly observed at 84x with the 38mm ocular, presenting a very good view in both telescopes. Argo Navis pointed right to it. At 84x Sirius initially appeared in the Obsession’s field of view at , ~ 1/3rd of the radius from the center of the field of view! Bravo! That alignment done in mid-January before all the cold weather hit is still working just fine! Sirius looked beautiful in the 120mm refractor too.
At 1h 40m MESSIER 79, a globular cluster in the constellation of Lepus, the Hare, just south of Orion, was located by the Argo Navis. M79 was exactly in the center of the field of view — I could not improve on its position in the ocular at 84x. It was a very good view. I do not believe that I have ever seen it before in my life. It is definitely worth a look, but is not as close or as spectacular as some globulars. It was also
At 1h 47m I attempted to observe the galaxy NGC 1744 in Lepus, but thin cloud and moonlight on snow hindered me. I think even a crescent Moon on snow gets too bright for most galaxy hunting — the sky is just not dark enough. Open clusters and globular clusters fare better. I think it glimpsed NGC 1744 in the center of my view, but not with certainty.
At 1h 52m I turned to Hind’s Crimson star, a famous deep red colored variable star, also in Lepus. It was visible a little off center in the field of view. It seems to have brightened somewhat since it was well seen in the 635mm Obsession five weeks ago, and its red color is quite obvious, although not quite as extreme as previously noted. At 1h 56m I had a brief view of MESSIER 41, a well-known open star cluster south of Sirius. The view was good in the Obsession at 84x, but I think the wider field of the 120mm (20x with the 50mm 2-inch diameter Orion Optilux eyepiece) was most impressive! A chest of gleaming diamonds could not look more beautiful. I am really glad to have both telescopes available for comparisons, and driven by the Argo Navis / ServoCAT system.
At 2h 00m, with the western half of the sky and the far southeastern sky clouding up with high, thin diffuse clouds, I turned to Saturn near the Cancer-Leo border. Used 84x and 124x (the 2-inch Astrola eyepiece) on the Obsession. The view was very good, especially initially. Four satellites were seen, and I am sure they were the usual suspects: Titan, Rhea, Dione, and Tethys. At one brief moment I glimpsed faintly a fifth, close to the
ball of the planet at ~ — possibly Enceladus. I have not yet had time to check the Astronomical Almanac for satellite positions. The rings appeared clearly with Cassini’s Division well seen; on the planet the tan equatorial belt was clear. I also looked at Saturn with the 120mm refractor (using 20x) and found Saturn’s disk and ring evident but the image far too small for satisfaction. On Saturn (and other planets) the big Obsession has all of the advantages, unlike the case of some of the brighter open star clusters.
At 2h 20m cloud began to thicken near Saturn and over much of the rest of the sky so I closed up. Although abbreviated by cloud, it was a very satisfying observing session. Dick Hodgson
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