Comprising many hours of RGB and H-alpha exposure, as well as many hours in processing all this data in a consistent way, the Parker/Carboni imaging team bring you a very busy region in the Constellation Cepheus – centred on the well known Cave nebula.  In this image you can see a lot of emission nebulosity, many dark nebulae, and dotted around the place several little reflection (blue) nebulae.  I think enough data has now been taken of this region for me to tick this one off the list and to move on to something new.

This image was taken with the Sky 90/M25C combination and is made up from 4 hours 10 minutes worth of RGB data and 6 hours and 25 minutes of H-alpha.  There is a great deal more emission nebulosity to be found off the right hand side of the frame, and I will probably try to capture this later in the year using the Hyperstar III.  This should hopefully take a lot less time than the 10 and a half hours the Sky 90 image required.

In 1980 (yes as late as that!) Lucian J. Kemble told Walter Scott Houston (see “Deep-Sky Wonders” in the books list) about a grouping of stars he had discovered.  Using 7 x 35 binoculars Kemble had found a cascade of stars in Camelopardalis that ended up on a little open cluster - NGC1502.  Houston called this asterism Kemble’s Cascade and the name stuck.  It is strange that the asterism does not show up on starmaps or planetarium programs, but clearly stands out when viewed through low-power binoculars.  It also takes some processing effort (as Noel will attest) to make the asterism appear in CCD data.  Clearly the eye-brain system applies some subtle contrast-enhancing wetware that non-discriminating cameras and photometric equipment do not apply!  This is not as strange, or unique as you might imagine.

 Take a pair of low-power binoculars, 10 x 50 are fine, and look at the Double Cluster in Perseus.  You will see an amazing ring of stars looking like a bracelet.  The Double Cluster is linked to the bracelet like a charm attached to a charm bracelet.  Now look at the same region of space on a star map or planetarium program – no bracelet.  Take a wide field CCD image of the region, the bracelet is barely distinguishable – yet go back to the binoculars again and it clearly stands out against all the background stars in the area.  Most strange!

La Superba or gamma Canum Venaticorum appears amazingly red to the observer.  It is a semi-regular variable star with a visual magnitude range of 4.8 to 6.3 and a period of 158 days.  It is amongst the brightest of the giant red carbon stars, this is the phase of a star’s life where energy generation is from helium-to-carbon fusion reactions.  There is an abundance of carbon compounds in the star’s outer atmosphere and these molecules tend to absorb short wavelength radiation leading to the star’s very red appearance.  The temperature of La Superba is very low at only 2200K which makes it one of the coolest true stars.

One of the brightest carbon stars (4400 times the luminosity of the Sun), and yet one of the coolest stars too (a rare J class carbon star at only 2200K) - try and find La Superba lying below the handle of the Plough (Ursa Major,Big Dipper).  R.A. 12h 45m 07.83s Dec. -45deg 26min 24.92sec.

It is extraordinary that by chance I imaged this one almost at the peak of its maximum and minimum about 18 months apart.  I was saying recently that I don’t believe in coincidence – I’ve just changed my mind on that! 

This star varies between something like magnitude 7 (brightest) and magnitude 14-15 (dimmest).  I had absolutely no idea that stars varied over this enormous range – thank you Roger Pickard at the BAA for educating me

Click on the image below for a larger version showing the “flashing” variable star.

 Looks like it may actually start off clear tonight, would do wouldn’t it with work tomorrow – but I must give this brilliant new system a trial if at all possible.  I’ll aim for a cluster in the Milky Way so I can keep to short subs and a short overall exposure time. I’m  now going to try and grab an hours kip.