Another week out (I take the series in counterattacking the weather). Another successful night. A part of the plain, to Conegliano, was under a dense fog. The foothills But it was free, so light pollution was not as small as possible. However we have found what for me is the night record, with the SQM rose to 21.83 (average of several readings with peaks at 21.86-21.88). SQM The two basic (and that of my Mars4ever) were quite in agreement, to ToolMaynard (an SQM-L) gives some more pessimistic reading (typically one tenth) but perhaps in part because of the night in which felt more was used the weight of the Milky Way overhead. Darkness is in fact increased as they went down the Milky Way, reaching a maximum at night with the galactic center at the zenith.
Light pollution was quite visible on the horizon Minimum only some slight glimmer in a sky that was more transparent in very low (allowing you to see many constellations Australia). The
Gegenshein, between Leo and Cancer, it was immediately apparent, almost easy. The first to notice it was ToolMaynard, before knowing the location where it should be. Looking a bit 'better you could also track the zodiacal band, although this was more difficult to see.
We spent some time looking to see M81 with the naked eye. I followed the method of Brian Skiff http://www.observers.org/tac.mailing.list/2001/July/0592.html. In particular, first identifying the star HD 83489 (mv 5.7) and HD 89343 = EN UMa (Mv 6). In the line that unites them, a quarter of the distance from the side of EN, was visible in the star HD 87703 mv 7.11. This star has been obvious to all, I would say that was visible at least 50% of the time. At half the distance from EN to the HD83489, there was another "thing" Skiff said to correspond to a trio of stars. To me it seemed (according to Skiff) more uncertain of the star of 7.11 even though the integrated magnitude of these is 6.8 (Skiff also reported as the most difficult of 7.11). There were other "things" around, but not along the line joining EN-HD83489. Along these lines, however, a quarter of the distance from the side but there had to be HD83489 M81. I had the impression of seeing her at the time which moved a bit by changing the eyes' diverted the direction of observation. In practice, when I observed in the distracted but maintain the angle at which I observed in diverted saw nothing, but suddenly the eye moving and moving slightly the point on the retina seemed to me to see an extended object, which then gradually disappeared from view.
Mars4ever ToolMaynard and did not see (but I'm the one who insisted more). In any case I can not be sure of seeing it as something that is really the limit and could also be suggestive. So far there are only very few people in the world who claim to have seen her, more or less with descriptions like this (in fact I did as Skiff http://www.seds.org/messier/xtra/supp/m81naked.txt ).
store this observation to the limits of the incredible (do not bet on that) here is a list of other objects observed and the progression of SQM and temperature. I searched for pictures if you like to see what the telescope (or at least not overly rich in detail that the telescope had not seen).
Haro 3-75 (Planetary Nebula in Orion), at 00:06. Not seen (but I was hasty, perhaps I have not identified educational purposes, since it is declared as an easy subject to a 24 "http://observing.skyhound.com/archives/jan/H_3-75.html).
21.68 SQM. Gegenshein the Visible between Cancer and Leo.
ngc2997 (Spiral Galaxy in Antlia), at 00:14. Front view. Bright nucleus and alone with traces of spirals.
IC 421 (Spiral Galaxy in Orion), at 00:24. It appears as a faint circular glow. An observation with a 20 "is shown here: http://www.visualdeepsky.org/logs/msg00195.html
NGC 2022 (Planetary Nebula in Orion), at 00:26. Observed at 265x. It looks like a elliptical disk (not distinguished the middle).
Abell 12 (Planetary Nebula in Orion), at 00:44. It looks like a small bubble immersed in the halo of light do mu Orionis (265x).
Unfortunately I suffered through the night a fluctuating situation of halos of light around the brightest stars, in part due to the fact that my expensive Ethos (otherwise excellent) have the vocation to condense inside (despite the anti bands Condesa), partly due to the fact that I have to redo the aluminizing of the primary (but here the discussion would be long).
21.71 SQM
NGC 2174 (Bright Nebula in Orion), at 01:06. Great nebula surrounding a star. Visible light than dark and dark nebulae in overlap (160x).
21.69 SQM, temperature -5 ° C
Observations of M81 with the naked eye.
21.72 SQM.
IC 342 (Spiral Galaxy in Camelopardalis), at 01:48. One can sense a vague swirl about half the field in 35 mm (100x). You see maybe a little 'better with UHC-S.
IC 356 (Spiral Galaxy in Camelopardalis), at 02:09. Small elliptical visible with 160x.
NGC 1560 (Spiral Galaxy in Camelopardalis), at 02:18. Cutting thin galaxy. Observed at 265x.
21.76 SQM, temperature -8 ° C
NGC 2146 / A (Spiral Galaxy in Camelopardalis), at 02:22.
NGC 2715 (Spiral Galaxy in Camelopardalis), at 02:43. "It looks like a spiral of three quarters."
21.80 SQM
NGC 2655 (Spiral Galaxy in Camelopardalis), at 02:48. I think we have seen the supernova (but did not know in advance where he was, but it was a very bright star on the edge of the galaxy).
Other observations of M81 with the naked eye.
NGC 2403 (Spiral Galaxy in Camelopardalis), at 03:09. He realized the spiral and an emission zone.
21.82 SQM
Messier 68 (Globular Cluster in Hydra), at 03:35.
Messier 100 (Spiral Galaxy in Coma Berenices), at 03:43. Spirals visible at 160x. Visible two smaller companions.
Coma Pinwheel Galaxy - Messier 99 (Spiral Galaxy in Coma Berenices), at 03:51. We see three spiral arms in 160x. At 265x you can see very well.
Abell 35 (Planetary Nebula in Hydra), 04:11 hours. Uncertain vision to the limit. OIII 100x.
21.83 SQM
Messier 83 (Spiral Galaxy in Hydra), at 04:15. Bar visible and dark between two bar loops and spirals, although a bit 'washed out due to the high horizon.
Note: when I seemed to see M81 also had the impression that it was still a floppy disk or an extended object. But I do not believe it myself because I would be among the few people in the world. As Brent says Archinal in response to Brian Skiff:
Congratulations on the naked-eye observation of M 81
. By my count, this Brings to four the number of people who
Been Able to do so, Including Stephen O'Meara, myself, and Aristides
Tzarellas (Webb Society Deep-Sky Observer, "Oct., 1996, p. 1). Could you also see
SAO 15100 (V = 7.2) to the east? This Was The faintest star visible
in the area (10 degrees above the horizon!) When I managed my
observation from Colorado.
Brent
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