View Nova Delphinus 2013 – A Limited Time Opportunity

nova and nebula

Nova Delphinus 2013 (left) and planetary nebula NGC 6905 (right), cropped at full scale from the same photograph taken on the evening of 24 August 2013. While I’m generally pleased with the images I took that evening, there is evidence of some problems on this 30 second exposure – the pulled out stars should all be points. More details follow below.

Although a lot has been made of two comets passing through our skies in 2013, August has given us an unpredictable and much rarer astronomical event: a nova, visible to the naked eye. Nova Delphinus 2013 has proven to be the brightest nova in five yeas – definitely worth a look. Novas are fleeting, however. There isn’t much time.

According to Space.com, Nova Delphinus 2013 was discovered on 14 August 2013 by Koichi Itagaki in Japan. Prior to brightening more than 100,000 times in its explosion, the star was a dim little 17th magnitude. It became as bright as 4th magnitude in the days since it was first spotted, and is now fading a bit. Over the coming days and weeks it will fade completely.

I set out on the evening of 24 August from our cottage in Bruce County to see if I could see it. Novas are exploding stars, and the initial flash doesn’t last too long. First, I had to find out the coordinates of this transient object.

The nova is located in the constellation Delphinus, the Dolphin, not too far from the “tip” of another constellation, the arrow, Sagita. The astronomical coordinates are RA. 20 h 23′ 31″, Dec. +20° 46′.

Some near-by land marks help, too:

  • Altair (α Aquilae), at 0.9 Magnitude, in Aquila, is the nearest very bright star.
  • Sualicin (α Delphini), 3.6 Magnitude, in the held of the dolphin, Delphinus, is the nearest named star.
  • A little blue planetary nebula, “The Blue Flash Nebula,” NGC 6905 is so close that it will appear in the same field of view through a wide-angle eyepiece. The 12th magnitude nebula is located at RA 20h 23m 02.52, Dec+20° 08’57.2″
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A wide-angle chart of the area of Nova Delphinus 2013, rendered with the freeware planetarium program Cartes du Ciel. This chart covers about 30° of the sky. The nova and the planetary nebula NGC 6905 are so close together that I’ve just indicated the nebula here.

chat2w

A narrow-angle drawing of the areas of Nova Delphinus 2013, prepared with Cartes du Ciel. This chart covers about 5°. The nova sits just within the boundaries of the constellation Delphinus (indicated by the faint purple lines).

As it will appear in most telescope mount “go to ” databases, finding NGC 6905 is a great way to get to the area of the nova quickly.

I set out to a gravel parking area near the Bruce Botanical Food Garden on the east side of Ripley, Ontario, at 8:30 PM on the evening of Saturday 24 August 2013 to see if I could spot the nova. I had found this site the night before, and it proved reasonably quiet, and fairly dark, although there are some near-by houses a few hundred yards away.

Some high clouds made the night of the 24th a little disappointing, and with moonrise set for 9:55 PM I knew I had to work fairly fast. I admit that I had trouble finding the nova with binoculars. I could see a fairly rich star field between Delphinus and Sagita, but really couldn’t decide if I was seeing my target or not.

I reverted to the aid of SynScan on my EQ6Pro mount to save the day, and wasn’t disappointed – eventually. I did found the nova, but only on photographs after the fact. Looking through a 28mm eyepiece on an 8” Newtonian, I couldn’t be sure at all what I was seeing. So, I re-reverted to imaging.

I set up a Nikon D800 body on the telescope, focused on a faint star using live view, and took a series of 30 second exposures at ISO 800. The nova turned out to be the brightest star in the frame, as expected. Actually, I spotted NGC 6905 first! The little blue ball was a charming sight on the photographs, and really stood out. I also have another admission, about NGC 6905. I didn’t know it was in the area of the nova until I saw my photos. At first I thought it was likely an artifact, but a quick check of the area on charts confirmed that in fact it was a planetary nebula, known as the Blue Flash Nebula. NGC 6905 is well worth a look on its own. It’s considered as a very lice planetary, and was discovered by William Herschel in 1782. This was another first for me – my first image of a planetary nebula. An added bonus for a night of nova hunting! The nova itself registered as a bright white star, bright enough to show faint diffraction spikes from the telescope’s secondary mirror spider.

photo1

Nova Delphinus 2013 (left) and the Blue Flash Nebula, NGC 6905 (right), photographed on the evening of 24 August 2013 at 9:51 PM EDT, from the east side of Ripley, Ontario. North is approximately toward the left. The single 30 second photograph was taken through a SkyWatcher 8” imaging Newtonian telescope with a coma corrector, and a Nikon D800 body, set to ISO 800, on an EQ6Pro mount. This copy has been reduced down in resolution and cropped from the original frame. The two smaller images at the head of the post are from the same frame, without reduction in resolution.

If weather and conditions permit, I recommend having a look for Nova Delphinus 2013. In the coming nights the moon will be rising later each night, and dropping in brightness, so this is a great time to try, while the nova is still bright. For southern Ontario Delphinus is nice and high in the sky after sunset. No reason not to go have a hunt for a truly rare sight!

Copyright © 2013 David Allan Galbraith
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