Browsing Archive: December, 2008
Posted by Mark Ashley on Wednesday, December 31, 2008,
In :
Galaxies
There are, I'm sure, plenty of contenders for the biggest and brightest object not included by Charles Messier in his famous catalogue of faint fuzzy objects which might have been mistaken for comets. Lying around 4 ° west of the nose of Leo, NGC 2903 must surely be near the top of the list. At around magnitude 10 (according to SEDS) and 13.3' along its major axis, this is a large and bright Sb+ spiral galaxy some 20.5 million light years from us. Despite NGC 2903 being missed by Messier, Gian... Continue reading ...
In late November and early December I imaged the dwarf planet Eris on several nights. Using Cartes du Ciel to help me pinpoint where she should be and the apparent movement of a faint object over the different nights I was fairly confident I had located the magnitude 18.7 dwarf planet. Here's my earlier post.
On the 28th December I tried again. With clearer skies I was able to image for longer to improve the signal-to-noise ratio. I'd also downloaded the Hubble Guide Star Catalogue to allow Ca... Continue reading ...
Discovered in 1994, Comet 144P/Kushida orbits the Sun every 7.6 years and is approaching its next perihelion on 26th January 2009 when it will be close to the Hyades in Taurus. This sequence, taken on 26th December 2008, shows the comet having just left Aries, moving into Taurus. Each frame is a 120s exposure, separated by 8 minutes. 144P/Kushida in Taurus. 10 120s exposures, 8 minutes separation Continue reading ...
On 23rd December the asteroid 2008 EV5 passed within 8.4 lunar distances of the earth. Its size (thought to be around 400m based on radar observations) and its orbit has led to it being designated a potentially hazardous object by the Minor Planet Centre (MPC).
Unfortunately 23rd December was cloudy in my location so I had to wait. When a clear night presented itself on Boxing Day, there was a problem with my ephemeris predicition and I missed my target! Finally, using emphemeris from the JPL ... Continue reading ...
At magnitude 16.6, this quasar in Lynx is probably the most distant object which average amateur setups can image. Despite being so faint, the object is actually very luminous, but also very distant. It has a red-shift of 3.87 which puts it at around 12.9 billion light years away from us. Although not visible on this monochrome image, the red-shift leads to a very deep red hue to the quasar. For a while this led people to believe it was a carbon star in our own galaxy. When its red-shift was ... Continue reading ...
Here is an image of the Type Ia supernova SN2008hv in NGC 2765, a magnitude 12.2 lenticular galaxy in Hydra. It was discovered on 2nd December 2008 by the CHASE project. Type Ia supernovae are a result of the catacylismic explosion of a white dwarf star.
At around magnitude 15, SN2008hv was an easy target and stands out clearly on this 2 hour, 40 minute image (taken from 5 minute subs) through my f/3.3 LX90 on an SXV-M7C camera.
 Continue reading ...
Posted by Mark Ashley on Friday, December 26, 2008,
In :
Galaxies
The Pegasus I cluster is dominated by the two elliptical galaxies NGC 7626 and NGC 7619, both 11th magnitude. NGC 7619 (centre) exhibits an X-ray tail and it is believed that this may be because there are two smaller galaxy clusters in the process of merging. Continue reading ...
Posted by Mark Ashley on Wednesday, December 24, 2008,
In :
Galaxies
The type Sb spiral galaxy NGC 772 lies in the constellation of Aries high in the Autumn skies when this image was taken on 24th November 2008. There is some distortion to its spiral shape which has led to its inclusion in the Arp catalogue of peculiar galaxies. The distortion is due to the tidal interactions between NGC 772 and its neighbour NGC 770, the dwarf elliptical galaxy to the south.  In 2003 two supernovae were discovered in NGC 772 within 3 weeks of one another, but these have long ... Continue reading ...
Posted by Mark Ashley on Sunday, December 21, 2008,
In :
Galaxies
This latest image is of the magnificent galaxy cluster Abell 426, part of the Abell Catalogue. There are at least 25 other galaxies visible in this image but in total the cluster has 400 members across 4 degrees of sky. Its brightest members are NGC 1272 and NGC 1275 (centre left and right). NGC 1275 is some 235 million light years away and is a type 1.5 Seyfert galaxy. In actual fact it is two galaxies, one in front of the other, although you can't see that on this image (click for an annota... Continue reading ...
During the Autumn there have been numerous modest comets traversing the skies (see the Comet Chasing website for a list of current comets). Two particularly well-placed comets for northern hemisphere observers have been C/2006 W3 (Christensen) and C/2006 OF2 (Broughton), the first and second images below.   Christensen, at magnitude 9.9, could be found moving quite rapidly across Cepheus during late November when this picture was taken and exhibited a 1' coma. Slightly larger with a 2' coma, Br... Continue reading ...
Here is a short sequence showing 9 Metis nudging northwards across the southerly regions of Aries last night, the 17th December 2008. There are 3 frames in the sequence, 10 minutes apart, each frame comprising a 60 second exposure. The motion isn't spectacular - I worked out that its motion would be about 2' in 10 hours, so you may struggle to detect 4-5" of drift in the elapsed 20 minutes of this sequence.

9 Metis (the '9' denoting that Metis was the 9th asteroid discovered) is 366km along ... Continue reading ...
Some may say the Horsehead nebula is over-used as a subject, however I find this iconic object so pleasing to image that I make no apologies. This is my latest attempt and suffers a little from some noise introduced due to occasional wispy high cloud. I've had to use a median filter to blur the worst bits of noise which resulted in a little loss of image sharpness. Nevertheless there's some reasonable definition around the nebula. I think also that there is more 'depth' to the nebula below th... Continue reading ...
Having taken three sets of images of Eris during November and early December, I think I've located her. At magnitude 18.7 this would be fair achievement with my 8" LX90. There's no way one image would be conclusive as the dwarf planet is only just above the background noise. But three images, corroborated by where Cartes du Ciel says she should be, means I'm reasonably confident. See the Minor Planets page for more on this.
 Continue reading ...
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About Me
| Mark Ashley |
| Dorset, United Kingdom |
Avid amateur astro-imager and sportsman.
I own an 8" Meade LX90 housed in a modest roll-off roof observatory in rural Dorset in the south-west of England. I've been astro-imaging since 2004 and particularly enjoy imaging galaxies.
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