September 9, 2012: four planetaries, on supernova, and one hedgehog

[michael.h.f.wilkinson]

Yesterday was clear again (apart from a persistent haze), but the skies were initially a bit better than the day before. I had set up the scope at dusk, so when I started observing around 10:00 PM, the scope was fully cooled. I had another bash at SN2012ei, and I could just make out some of the nearby mag 13.5-13.7 stars, and in their midst, the fitful twinkle of the SN. I think is was about mag 13.5. Very difficult, due to the hazy conditions (normally I can reach mag 14-14.2 with my scope under transparent conditions). The XW10 EP showed it most clearly. The host galaxy could not be seen.

Next I went to Hercules, to find NGC 6210 in Hercules. This is an easy star-hop from beta Herculi, and at mag 9, could be spotted in the 70mm finder scope. It is a planetary nebula of very high surface brightness, compact and easily seen without UHC filter. Best views at 203x with UHC filter in the Pentax XW10, which shows its extension (only 16") best. Some way below, still in Hercules, star-hopping southwards from gamma Herculi, I found IC 4593, also known as the White-eyed Pea. At mag 11, much fainter than the previous one, but still easily resolved (12", not 2'00" as listed in Stellarium).

I then moved to Ophiuchus, and got NGC 6572, sometimes called the Blue Racquetball. This was easy at mag 8.5 (visible in the finder scope) and at 14" diameter, has a high surface brightness. The blue-green colour was quite evident.

I briefly tried NGC 6886 in Sagitta, but I could not find it. It is near-stellar object, only 8" in diameter, so unresolved in my finder EP. At mag 12, there are just too many candidate stars to inspect without a very detailed finder chart (must prepare better, and draw them up in stellarium). I did spend quite some time pouring over my sky atlas, looking through the scope, switching filters. As I was doing this, there was a lot of rustling in the plants in the garden beside me, and a small creature came running out onto the garden path beside me. I had a look to verify it what it was, by turning on a little bit of light (pointed away from the creature so as not to startle it). It was a hedgehog, which froze the moment it realized there was something big just a few feet away. I walked away from the scope to my star charts, which instantly unfroze the little creature and it darted back into the safety of the flower bed.

Next up was NGC 6741, or the Phantom Streak. This is also very compact, but armed with a decent position estimate from my map, I located a near stellar object which did not fade wit the stars when the UHC filter was inserted. The XW10 showed hints of some extension, but I will need much better seeing conditions to properly resolve this 6"x8" object.

Two final attempts at bagging more PNs failed, as NGC 6842 at mag 13.0 and with an extent of 48" is beyond the scope under these conditions: I know I pinpointed the right position, but the haze was too bad. At least I know where to look. NGC 6884 is near stellar, in a rich star field, so I got lost looking for it. Again, I must draw up good maps for these objects before trying again.

Still: four more PNs bagged, so I retired to bed quite happily.

[Double Kick Drum]

Thanks for sharing another productive session.

Seven supernovae sighted already is really good going. It's not long since your first one, yeah?

I too thought I could see colour in NGC 6572. Both this and NGC 6210 are both bright and suitable for quite small scopes, all be it with a fair bit of magnification. Anyone wanting to expand their viewing list beyond Messiers should consider these two.

The others are beyond me for the time being.

[michael.h.f.wilkinson]

Thanks for sharing another productive session.

Seven supernovae sighted already is really good going. It's not long since your first one, yeah?

I too thought I could see colour in NGC 6572. Both this and NGC 6210 are both bright and suitable for quite small scopes, all be it with a fair bit of magnification. Anyone wanting to expand their viewing list beyond Messiers should consider these two.

The others are beyond me for the time being.

Cheers, Martin. My first SN (SN2011b) was bagged on January 28, 2011 in Camelopardalis, which makes about 3-4 SN per year. This has less to do with observing skill than with aperture: brighter SN are rarer. If I upgrade to a 16" Dob, I coud get far more!

[Mr Flibble]

Good stuff . I like the way you use the UHC to find the stellar-like objects. I'm still finding the easy stuff and haven't needed to do this yet. Just wondering, do you find it easier to screw the filter in or just hold it over the top of the eyepiece?

[michael.h.f.wilkinson]

I always screw it in. It is too reflective to use otherwise. I am thinking about getting a filter wheel.