Observing report - Moon passes Pleiades
Although I did not expect to be able to see the Pleiades just a few minutes after civil sunset, at 6:00pm I put a small 60mm refractor on the Moon and was rewarded with a nice view of a shadow ray in Clavius on the Moon and 5 Pleiadan stars shining from a steel blue-grey sky. Taygetae 19 Tau, Mai 20 Tau, Electra 17 Tau, a fainter Celaneo 16 Tau and the Moon were visible in a 1.2 deg TFOV. One field away, Alycone 25 Tau and Merope 23 Tau could be seen. At 6:03pm, Taygeta winked off during ingress behind the dark limb. Celaneo 20 was a lunar grazer that passed a few arc minutes below the south pole and terminator, but was never obscured. The sky color was quite pleasing and I think in the future I will look at the Moon under similar conditions instead of waiting for it to get dark. By 6:15pm, Maia 20 Tau was just beginning its own lunar south pole graze. I packed it up for while. At 6:55pm, I again set up the small refractor to watch egress of two Pleiaden stars on the bright limb. Mai 20 Tau was ending its wide-field graze-pass of the south pole. At about 7:00pm, I took a break from the eyepiece, looked up and there was a great pass by the ISS at about -2 mags from the northwest to the south east at about 35 degs alt. (Checked and it shows up on the NASA ISS Sighting Calculator. I had not thought to check for ISS overflights tonight.) A few minutes later, fainter 5.6v 18 Tau egressed on the bright limb. With 60mm of aperture, I did not see the moment of egress. It was overwhelmed by bright limb. About five minutes after egress it was sufficiently far (2 or 3 arcminutes) from the bright limb to be detected. This was a rare nice observing day for me: At 5am, I went out and took a look at Comet Lulin, a peak at Saturn and the "Y" shaped Struve 761-762 system around sigma Orion. Around 11:30am, a quick peak for small prominences off the Sun's limb with the PST. 6pm - Moon and an occulted star ingress. 7pm - Satellite overpass and an occulted star egress. I decided to pass looking for Comet Kushida in Tau. The Moon was within 20 degrees and it did not seem to be worth the trouble, but I see Patrick got an image. Overslept on the 1:22am Vandenberg launch. - Kurt Some background reading: Weaver, H.R. 1947. The Visibility of Stars without Optical Aid. (Visibility of stars near sunset.) http://adsabs.harvard.edu/abs/1947PASP...59..232W
On 04 Feb 2009, at 02:33, Canopus56 wrote:
Overslept on the 1:22am Vandenberg launch.
You get a reprieve. :) This just showed up in my inbox: +++++ DELTA II LAUNCH DELAYED Vandenberg AFB News Release 2009 February 4 VANDENBERG AFB, Calif. - The launch of a Delta II rocket from Space Launch Complex-2 has been rescheduled due to a problem with the launch pad. The next launch attempt is scheduled for Thursday at 2:22 a.m., weather permitting. +++++ patrick
I found a good spot on the front yard. But I noodled over my blog until less than an hour before the event was to start, then tore around wildly setting up the telescope on the tripod and wedge. I had a great deal of trouble getting the two secondary bolts in, among those that hold the telescope to the wedge. By the time I finished I had no time to get the camera going before the start of the event. Looking through the finder scope, I saw that the moon and atmosphere were bright and thought they obscured the stars even on the moon’s darker side. (Obviously I was wrong and the finder didn't give enough detail, judging from Kurt's report.) Maybe I should try for the egress, when the sky will be dark, I decided. Cory and I had supper and I went back to work. But when it was dark I thought I couldn’t photograph anything because the moon’s neighborhood seemed too washed out. I decided to relax a bit, then show the Orion Nebula to Cory and, later, take some more photos of that nebula to add to my mosaic. When I went back outside my first clue something was wrong was that my flashlight set off glitters in the grass. A heavy frost had descended from the clear sky and covered everything. My equipment bags were soggy and the telescope’s corrector plate was covered with white frost. I asked Cory if she had a hair-drier so I could get rid of the frost. She didn't. (She has no hair-drier and I have no hair.) For a time I tried to evaporate the rime with my space heater, but that only turned the frost to water. I gave up and hauled everything back inside, dragging my telescope upstairs via hand truck. Now I'll have to clean the plate because the frost left crud all over it.-- Best wishes, Joe --- On Wed, 2/4/09, Canopus56 <canopus56@yahoo.com> wrote: From: Canopus56 <canopus56@yahoo.com> Subject: [Utah-astronomy] Observing report - Moon passes Pleiades To: "Utah Astronomy List Serv" <utah-astronomy@mailman.xmission.com> Date: Wednesday, February 4, 2009, 2:33 AM Although I did not expect to be able to see the Pleiades just a few minutes after civil sunset, at 6:00pm I put a small 60mm refractor on the Moon and was rewarded with a nice view of a shadow ray in Clavius on the Moon and 5 Pleiadan stars shining from a steel blue-grey sky. Taygetae 19 Tau, Mai 20 Tau, Electra 17 Tau, a fainter Celaneo 16 Tau and the Moon were visible in a 1.2 deg TFOV. One field away, Alycone 25 Tau and Merope 23 Tau could be seen. At 6:03pm, Taygeta winked off during ingress behind the dark limb. Celaneo 20 was a lunar grazer that passed a few arc minutes below the south pole and terminator, but was never obscured. The sky color was quite pleasing and I think in the future I will look at the Moon under similar conditions instead of waiting for it to get dark. By 6:15pm, Maia 20 Tau was just beginning its own lunar south pole graze. I packed it up for while. At 6:55pm, I again set up the small refractor to watch egress of two Pleiaden stars on the bright limb. Mai 20 Tau was ending its wide-field graze-pass of the south pole. At about 7:00pm, I took a break from the eyepiece, looked up and there was a great pass by the ISS at about -2 mags from the northwest to the south east at about 35 degs alt. (Checked and it shows up on the NASA ISS Sighting Calculator. I had not thought to check for ISS overflights tonight.) A few minutes later, fainter 5.6v 18 Tau egressed on the bright limb. With 60mm of aperture, I did not see the moment of egress. It was overwhelmed by bright limb. About five minutes after egress it was sufficiently far (2 or 3 arcminutes) from the bright limb to be detected. This was a rare nice observing day for me: At 5am, I went out and took a look at Comet Lulin, a peak at Saturn and the "Y" shaped Struve 761-762 system around sigma Orion. Around 11:30am, a quick peak for small prominences off the Sun's limb with the PST. 6pm - Moon and an occulted star ingress. 7pm - Satellite overpass and an occulted star egress. I decided to pass looking for Comet Kushida in Tau. The Moon was within 20 degrees and it did not seem to be worth the trouble, but I see Patrick got an image. Overslept on the 1:22am Vandenberg launch. - Kurt Some background reading: Weaver, H.R. 1947. The Visibility of Stars without Optical Aid. (Visibility of stars near sunset.) http://adsabs.harvard.edu/abs/1947PASP...59..232W _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com
Hi Joe, Sorry to hear about your problems. Are you using a dew cap? I use one on my scope year round to keep frost off in the winter and dew off the rest of the year. Nothing fancy, BTW, with my C-8 I used to use a paper grocery bag I cut the bottom out of. For the C-14 I use foam padding material I got in a roll from Sears (they sell it for lining the bottoms of tool box trays). Rule of thumb is to make it at least as long as the scope is wide. But even that isn't enough for all-night protection. Eventually you'll need to use one of the dew zappers being made for scopes or a hair drier (they make 12VDC hair driers for use in the field). If you look at my light curves you'll see breaks in the data every hour or so where I took the scope off line for a few minutes to remove frost or dew. And don't be too concerned about the corrector plate. I clean mine maybe once a year. It's pretty much impossible to keep it clean all the time and you don't want to risk messing up the coatings. Plus you'd be surprised how bad it can look but still be ok. patrick On 04 Feb 2009, at 09:32, Joe Bauman wrote:
I found a good spot on the front yard. But I noodled over my blog until less than an hour before the event was to start, then tore around wildly setting up the telescope on the tripod and wedge. I had a great deal of trouble getting the two secondary bolts in, among those that hold the telescope to the wedge. By the time I finished I had no time to get the camera going before the start of the event. Looking through the finder scope, I saw that the moon and atmosphere were bright and thought they obscured the stars even on the moon’s darker side. (Obviously I was wrong and the finder didn't give enough detail, judging from Kurt's report.) Maybe I should try for the egress, when the sky will be dark, I decided. Cory and I had supper and I went back to work. But when it was dark I thought I couldn’t photograph anything because the moon’s neighborhood seemed too washed out. I decided to relax a bit, then show the Orion Nebula to Cory and, later, take some more photos of that nebula to add to my mosaic. When I went back outside my first clue something was wrong was that my flashlight set off glitters in the grass. A heavy frost had descended from the clear sky and covered everything. My equipment bags were soggy and the telescope’s corrector plate was covered with white frost. I asked Cory if she had a hair-drier so I could get rid of the frost. She didn't. (She has no hair-drier and I have no hair.) For a time I tried to evaporate the rime with my space heater, but that only turned the frost to water. I gave up and hauled everything back inside, dragging my telescope upstairs via hand truck. Now I'll have to clean the plate because the frost left crud all over it.-- Best wishes, Joe
Thanks, Patrick. This on looks so bad I really do need to clean it; it's just covered. There was a lot of gunk in the SLC inversion and that came out with the frost. Pretty ugly. Don't worry, I'll be really careful. Best wishes, Joe --- On Wed, 2/4/09, Patrick Wiggins <paw@wirelessbeehive.com> wrote: From: Patrick Wiggins <paw@wirelessbeehive.com> Subject: Re: [Utah-astronomy] Non-Observing report - Moon passes Pleiades To: "Utah Astronomy" <utah-astronomy@mailman.xmission.com> Date: Wednesday, February 4, 2009, 4:24 PM Hi Joe, Sorry to hear about your problems. Are you using a dew cap? I use one on my scope year round to keep frost off in the winter and dew off the rest of the year. Nothing fancy, BTW, with my C-8 I used to use a paper grocery bag I cut the bottom out of. For the C-14 I use foam padding material I got in a roll from Sears (they sell it for lining the bottoms of tool box trays). Rule of thumb is to make it at least as long as the scope is wide. But even that isn't enough for all-night protection. Eventually you'll need to use one of the dew zappers being made for scopes or a hair drier (they make 12VDC hair driers for use in the field). If you look at my light curves you'll see breaks in the data every hour or so where I took the scope off line for a few minutes to remove frost or dew. And don't be too concerned about the corrector plate. I clean mine maybe once a year. It's pretty much impossible to keep it clean all the time and you don't want to risk messing up the coatings. Plus you'd be surprised how bad it can look but still be ok. patrick On 04 Feb 2009, at 09:32, Joe Bauman wrote:
I found a good spot on the front yard. But I noodled over my blog until less than an hour before the event was to start, then tore around wildly setting up the telescope on the tripod and wedge. I had a great deal of trouble getting the two secondary bolts in, among those that hold the telescope to the wedge. By the time I finished I had no time to get the camera going before the start of the event. Looking through the finder scope, I saw that the moon and atmosphere were bright and thought they obscured the stars even on the moon’s darker side. (Obviously I was wrong and the finder didn't give enough detail, judging from Kurt's report.) Maybe I should try for the egress, when the sky will be dark, I decided. Cory and I had supper and I went back to work. But when it was dark I thought I couldn’t photograph anything because the moon’s neighborhood seemed too washed out. I decided to relax a bit, then show the Orion Nebula to Cory and, later, take some more photos of that nebula to add to my mosaic. When I went back outside my first clue something was wrong was that my flashlight set off glitters in the grass. A heavy frost had descended from the clear sky and covered everything. My equipment bags were soggy and the telescope’s corrector plate was covered with white frost. I asked Cory if she had a hair-drier so I could get rid of the frost. She didn't. (She has no hair-drier and I have no hair.) For a time I tried to evaporate the rime with my space heater, but that only turned the frost to water. I gave up and hauled everything back inside, dragging my telescope upstairs via hand truck. Now I'll have to clean the plate because the frost left crud all over it.-- Best wishes, Joe
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Remember, you don't need to keep optics warm to the touch to prevent condensation. Just a tad warmer than the dew point is sufficient.
I took out my Zhumell 8" dob to take a look at the event in my backyard in Orem. Temperature was actually quite nice to begin with, but got colder as the evening progressed. My 2" 25mm eyepiece gave some very pleasing views of the dark limb with some of the Pleiades in the background. If I kept the lit part of the moon out of the eyepiece I could see a number of stars in the cluster next to the dark limb, I don't know the sky well enough to be able to tell you which ones they were :-). This was maybe 6:30, 7pm or so. Switching over to my 9mm ep, I was able to watch the dark limb swallow up a couple of the members of the cluster. That was fun to watch. Either the seeing was better last night than previous nights in the last month, or I did a better job of collimating this time around. I recently collimated my laser collimator so maybe that helped in that department. This scope is proving oh-so-much nicer to use than the 4.5" Bushnell reflector on an eq mount I used to have to fight with :-). Dan On Wed, Feb 4, 2009 at 2:33 AM, Canopus56 <canopus56@yahoo.com> wrote:
Although I did not expect to be able to see the Pleiades just a few minutes after civil sunset, at 6:00pm I put a small 60mm refractor on the Moon and was rewarded with a nice view of a shadow ray in Clavius on the Moon and 5 Pleiadan stars shining from a steel blue-grey sky. Taygetae 19 Tau, Mai 20 Tau, Electra 17 Tau, a fainter Celaneo 16 Tau and the Moon were visible in a 1.2 deg TFOV. One field away, Alycone 25 Tau and Merope 23 Tau could be seen. At 6:03pm, Taygeta winked off during ingress behind the dark limb. Celaneo 20 was a lunar grazer that passed a few arc minutes below the south pole and terminator, but was never obscured. The sky color was quite pleasing and I think in the future I will look at the Moon under similar conditions instead of waiting for it to get dark.
By 6:15pm, Maia 20 Tau was just beginning its own lunar south pole graze. I packed it up for while.
At 6:55pm, I again set up the small refractor to watch egress of two Pleiaden stars on the bright limb. Mai 20 Tau was ending its wide-field graze-pass of the south pole.
At about 7:00pm, I took a break from the eyepiece, looked up and there was a great pass by the ISS at about -2 mags from the northwest to the south east at about 35 degs alt. (Checked and it shows up on the NASA ISS Sighting Calculator. I had not thought to check for ISS overflights tonight.)
A few minutes later, fainter 5.6v 18 Tau egressed on the bright limb. With 60mm of aperture, I did not see the moment of egress. It was overwhelmed by bright limb. About five minutes after egress it was sufficiently far (2 or 3 arcminutes) from the bright limb to be detected.
This was a rare nice observing day for me:
At 5am, I went out and took a look at Comet Lulin, a peak at Saturn and the "Y" shaped Struve 761-762 system around sigma Orion.
Around 11:30am, a quick peak for small prominences off the Sun's limb with the PST.
6pm - Moon and an occulted star ingress.
7pm - Satellite overpass and an occulted star egress. I decided to pass looking for Comet Kushida in Tau. The Moon was within 20 degrees and it did not seem to be worth the trouble, but I see Patrick got an image.
Overslept on the 1:22am Vandenberg launch. - Kurt
Some background reading:
Weaver, H.R. 1947. The Visibility of Stars without Optical Aid. (Visibility of stars near sunset.) http://adsabs.harvard.edu/abs/1947PASP...59..232W
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Zhumell is a brand-name. I believe their scopes are manufactured by the Guan Sheng Optics company (Taiwan), which also manufactures for other brands. The scope I got is detailed and sold here: http://www.telescopes.com/telescopes/dobsonian-telescopes/zhumellz8deluxedob.... I was originally looking at an Orion XT8, but the better accessory package from the Zhumell, free shipping, and the good reviews won me over to Zhumell. I been very pleased with the purchase so far. For $379 you get: - 8" aperture - A RACI 8x50 finder scope - Crayford focuser - Primary mirror battery-powered cooling fan - 2 eyepieces (2" 30mm and a 1.25" 9mm) (I mis-remembered the mm size of the 2" in my observation report) - A "moon filter" for the 1.25" ep - A laser collimator (which I had to collimate) - Knobs for collimating the primary mirror (no wrenches or screwdrivers required) - They throw in a nice-quality green laser pointer as well for free. - The alt and az tension systems are adjustable and provide very nice movement. I think some of the images on the website are from the non-deluxe model. All-in-all, for the price it's a really nice package to get going in astronomy. I've been really happy with it thus far. Small enough to be fairly portable (Fits assembled in the back of our Honda Odyssey), but enough aperture to give some really nice views. Now I just need to learn the sky a bit better. Down the road, I'm hoping to get a Telrad finder and to expand my eyepiece collection. So far, though I have plenty to keep me busy for a while. I hope to write up a full review if I can find the time. Dan On Wed, Feb 4, 2009 at 7:00 PM, Chuck Hards <chuck.hards@gmail.com> wrote:
Dan, what is a "Zhumell" Dob? Never heard of it. Is it an optical configuration, or a manufacturer?
On Wed, Feb 4, 2009 at 5:41 PM, Dan Hanks <danhanks@gmail.com> wrote:
I took out my Zhumell 8" dob
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participants (5)
-
Canopus56 -
Chuck Hards -
Dan Hanks -
Joe Bauman -
Patrick Wiggins