Marc Murison's Amateur Astronomy Weblog http://www.alpheratz.net/observing/ Marc Murison's Amateur Astronomy Weblog en murison@alpheratz.net Copyright 2006 2006-05-10T17:10:00-05:00 M3 on May 06, 2006 http://www.alpheratz.net/observing/m3_on_may_06_2006/ deep sky objects M3 (NGC 5272).  Total integration time 160×10.0 sec = 26.7 min. The extent of this image is shown by the box on the image of M3 in the May 3 observing session. M3 is 10.4 kpc from the Sun. The V magnitude of the horizontal branch is 15.7.

]]> 2006-05-10T17:10:00-05:00 M53, M3, and NGC 4631 on May 03, 2006 http://www.alpheratz.net/observing/m53_m3_and_ngc_4631_on_may_03_2006/ deep sky objects M53 (NGC 5024).  Total integration time 122×15.0 sec = 30.5 min. M53 is 17.8 kpc from the Sun. The V magnitude of the horizontal branch is 16.8.  This is the inaugural image of my new Meade DSI Pro II CCD camera.

M3 (NGC 5272).  Total integration time 149×11.3 sec = 28 min. The box shows the extent of the image of M3 shown in the May 6 observing session. M3 is 10.4 kpc from the Sun. The V magnitude of the horizontal branch is 15.7.

NGC 4631.  Total integration time 243×15.0 sec = 61 min.

]]> 2006-05-04T20:48:00-05:00 h Per, NGC7331, M56, and NGC281 on September 28, 2005 http://www.alpheratz.net/observing/h_per_ngc7331_m56_and_ngc281_on_september_28_2005/ deep sky objects h Per on September 28, 2005.  Prime focus (f/8.0).  Total integration time 164×8.53 sec = 23 min.  This is central core of h Per, an open cluster of about 320 stars that is stunning in a pair of binoculars or at low magnification in a telescope.  It is about 2,230 pc distant.

NGC 7331 on September 28, 2005.  Prime focus (f/8.0).  Total integration time 430×8.53 sec = 61 min.

M56 (NGC 6779).  Total integration time 424×8.53 sec = 60 min.  This globular cluster lies roughly 9,800 pc distant.  The horizontal branch (HB) of this cluster is at V magnitude 16.3, which is the magnitude at which large numbers of cluster stars become visible.

NGC 281 on September 28, 2005.  Prime focus (f/8.0).  Total integration time 209×8.53 sec = 30 min.  NGC 281 is the nebulosity associated with the open cluster IC 1590

]]> 2005-10-04T02:20:21-05:00 Veil Nebula, M92, and NGC6229 on August 24, 2005 http://www.alpheratz.net/observing/veil_nebula_m92_and_ngc6229_on_august_24_2005/ deep sky objects NGC 6992 (Veil Nebula) on August 24, 2005.  Prime focus (f/8.0).  Total integration time 486×8.53 sec = 69 min.  This is a small section in the NNE part of the Veil Nebula.

NGC 6229.  Total integration time 446×8.53 sec = 63 min.  This is a faint globular cluster, roughly 91,000 to 103,000 light years distant — clear across the Galaxy from us.  The V magnitude of the horizontal branch is 18.0, so we’re mainly seeing the brightest cluster members in this image.  (The brightest cluster star is V=15.5.) Note the faint "stars" NE of foreground stars HD151651 and HD151689.  I suspect these are due to internal reflections from the minus-violet filter (and perhaps the CCD cover glass).

M92 (NGC 6341).  Total integration time 185×8.53 sec = 26 min.  This globular cluster lies 24,000 to 33,000 light years distant.  The core in this image is overexposed.  The horizontal branch (HB) of this cluster is at V magnitude 15.2, which is therefore the magnitude at which large numbers of cluster stars become visible.  This HB magnitude is only slightly brighter than the brightest star in NGC 6229!

]]> 2005-08-24T15:08:37-05:00 M29 on August 2, 2005 http://www.alpheratz.net/observing/m29_on_august_2_2005/ deep sky objects M29 (NGC 6913).  Total integration time 316×8.53 sec = 45 min.  This is a sparse open cluster of about 80-100 stars (integrated magnitude 6.6) whose brightest star is mag. 9.0.  It lies 4380 light years distant.

]]> 2005-08-02T19:46:34-05:00 M71 on July 31, 2005 http://www.alpheratz.net/observing/m71_on_july_31_2005/ deep sky objects M71 (NGC 6838).  Total integration time 390×8.53 sec = 55 min.  This is a relatively sparse globular cluster whose brightest star is mag. 12.1 and whose horizontal branch is at mag. 14.5.  It lies 13,000 light years distant.

]]> 2005-07-31T19:32:29-05:00 AR0789 on July 12, 2005 http://www.alpheratz.net/observing/ar0789_on_july_12_2005/ solar images

]]> 2005-07-28T02:03:55-05:00 List of Known Exoplanets http://www.alpheratz.net/observing/list_of_known_exoplanets/ other I have compiled a list of known exoplanets, including a SkyTools 2 observing list.

]]> 2005-07-11T15:56:02-05:00 Venus and Mercury Appulse http://www.alpheratz.net/observing/venus_and_mercury_appulse/ planets I managed to observe the 4 arcminute separation between Venus and Mercury today.  See the full report for details, images, and a movie!



]]> 2005-06-28T13:15:12-05:00 M13, M27, M57, and NGC 5466 on 17 June 2005 http://www.alpheratz.net/observing/m13_m27_m57_and_ngc_5466_on_17_june_2005/ deep sky objects
M13.  Total integration time 137×8.53 sec = 19.5 min.



M27 (the Dumbbell Nebula).  Total integration time 419×8.53 sec = 60 min.



M57 (the Ring Nebula).  Total integration time 280×8.53 sec = 40 min.  The V magnitudes shown are from photometry of M57 field stars taken by Arne Hendon (USNO-Flagstaff).  See Brian Skiff’s page on M57 field star photometry for more information.



NGC 5466 on June 17, 2005.  Prime focus (f/8.0).  Total integration time 349×8.53 sec = 50 min.  This is a faint, sparse globular cluster, roughly 52,000 light years distant.


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