Date: Mar 5th 2011 Saturday
Observation Time: 7pm to 11:30pm (observing time ~3:30 hrs),
Location: Jon's Home, Boulevard, CA
Weather: not great.. partly cloudy so looking thru patches. No wind. Seeing wasn't great 5/10.
Instruments: Jon's new 25" f/5 Obsession telescope
Buddies: Jon & Ashwin
Lot of new things to begin with for this observing session.
- Jon's new 25" obsession scope. Its massive. Need to climb 8 foot ladder to observe at zenith.
- First session of 2011
- Welcome Gogol session.
- Finished all 110 messier objects.. not in one night, but in 3 years period :). All messier objects are observed atleast once now. It was sort of 3-year messier marathon.
Ashwin joined for this session, first time at Jon's place.
Recently Jon purchased 25" obsession telescope. It is a used telescope and has a chip on the back side of the mirror. Jon got an excellent deal for the scope without much compromise. Its obsession scope #511.
Irrespective of the massive size, the scope movement is very smooth from the top of the ladder. It shows really nice views.
Mirror: 25"
Focal Length : f/5 3110mm. With parracor : ~3658mm
So now a 31mm Nagler low mag eyepiece from 16" scope, suddenly gives 100x view in 25" scope. Its not low mag eyepiece anymore.
Can clearly show 500x zooming with sharp images. Can easily go to 800x with decent views.
The Collimation took longer than expected. Jon is still getting familiar with the movement of secondary mirror screws. Primary alignment was quick. Also, the collimation stayed fine whole observing session. Considering the amount of scope movement, its indeed stable.
For such a big scope, generally it makses sense to observe all the objects in the vicinity and then to move on to the next location in the sky. But becasue of clouds, we ended up jumping from one location to opposite one and moved the scope and ladder a lot. We ended up doing ~10-15 circles/360deg rotations with the scope, during the night. Still, I am listing the objects per constellation and with the flow of the observing sessions.
Perseus
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M76 - little dumbbell nebula: Started the night with M76. not a object that will impress immediately, but details on M76 was nice. Can clearly see two lobes, sort of in hourglass shape. The brightness was enough. Considering mirror cool-down time and cloudy weather, it indeed showed more than enough details on the object.
Orion
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M42 - M43 orion nebula : Switched to Orion M42 masterpiece. In 31 Nagler @ 118x, the eyepiece was fully covered under the nebula. the saucer, the pillar and the trapezoid was fabulous. Very bright. More you look at it, can feel the depth.. Had3D effect. Trapezoid clearly shows 6 stars. Double speed focuser indeed gives pinpoint stars of #5 and #6 in trapezoid. With 20mm Nagler @ 182x, magnifies it to the dark pillar. In contrast, the trapezoid and the illumination of the gas around it was very bright. Because of bright nebulousity all around and the central pillar being so dark, sort of looses the typical shape. M43 itself shows lot of bright nebulosity. Talked about running man nebula nearby, but wasn't sure about the location. Next time TBD.
M78 - The nebulosity pops up because of bigger aperture. A Bright star in the view. Hard to remember, because of lack of discernible shape, but definitely filled ~10% of the eyepiece.
Rigel - Visited Rigel multiple times in the night. At 118x can clearly see the companion. Rigel was sharp, but the companion wasn't.. tried to focus, but it still seemed like blurry disk. companion ~9.8" separation. Very close to Rigel. Later visted it again with ~400x. This is to compare with Sirius. Just wanted to get a judgment on how 10" separation looks like at ~400x.
Canis Major
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M46-47 : with 20 Nagler, at 182x, the hwole view was filled with bright stars of M46. In reality, M46 has fainter stars than M47, but with large aperture of 25" makes M46 such a bright object. the planetory nebula is in the view on the right-bottom side. A faint star at the center of it is visible. not sure if its part of the cluster or the planetory star itself. At 182x, M47 is infact dull object, though it has bright stars its really sparse object. Hence nothing impressive in their. With 31 Nagler, 118x, both objects never fit in the same view and hence the beauty of observing both in wide-view is sort of lost. but 31 nagler still shows M46 as an impressive object.
M93 - This was yet another OC.
NGC 2467 - object opposite to M93. - The nebulosity in the object is very distinct in the big aperture. Sort of big C shaped nebulosity. Next to it is the Open cluster in V shape, similar to Taurus.
Sirius - Tried splitting Sirius. Difficult part here is Sirius is too bright compared to the companion and hence very difficult to observe the companion. Also its only 10" seconds apart. Only thing I knew tabout it is that its following sirius. Hence i kept Sirius barely out of the view and tried to look for the companion, but it was hard. Sirius light rays were causing trouble. Secondly wasn't sure how much 10" distance seems at 400x. So thought that another faint star is its companion. To get the judgment on 10" separation in 400x, tried Rigel. that proved that the faint star i was looking at was wrong. 10" is still too close in 400x. FAILED to observe the companion. Need better seeing/stability for this one.
Beta Monoceros - Observed the triplet, during the last session of observing. Triplet system with a tight bright pair. No colors, all three were yellow.
Ursa Major
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M81-M82 : M81 seemed like a big elliptical fuzzy object. Very bright. But M82 was more impressive, with distinct edge-on and some motteling on it at the center in Y axis.
M51 : Visited M51 probably 3 times during the night. The object moved from horizon - 5deg to -30-45 deg in 3 hrs. In the last session, the details on the object were clear, Can easily trace the spiral structure fomr the center to the connecting NGC galaxy. Actual Connector betn both of them was not visible. Some Nebulas or brighter regions in the spiral of M51 were visible. Don't remember the exact location of these regions. More eyepiece time + dark adaptation, gives more details on this object. Definitely saw more details on M51 visually for first time.
M101 : The brighter part at the core is visible. Jon mentioned that this is a big object and can not fit in the view itself.. I didn't see much in this one except the fuzziness at the core.
Canes Venatici
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Galaxy Quintet near M51 - Hickson 68 - NGC 5354 + 4 more : This is actualy in CVn and not in UMa. Jon pointed to this one.. Seemed like typical Jon object :). Very faint galaxy group, made up of 5 galaxies. Two of them were (relatively) bright, while remaining were barely visible. Very faint. The brighter NGC 5354 is of mag +11.38, while the lowest one on the left NGC-5358 is of 14.57. this is just to know that Jon's scope goes till +15 mag, without much trouble. Have I seen this one before? (YES, I have. check older observations)
Continued..
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