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It should still be visible in 10 x 50’s if your skies are good enough to show M33 in same. I could still see it in my 7 x 50’s a few nights ago. Have you got the latest coordinates? It’s 1 degree 16 mins to the right (NE) of Omicrom at 10pm tonight.
Andrew
Just checking my binary calculator Gary, at the start of 1978 it would have been at a separation of 10.8″ and PA 53 degrees. Ditto 1979, sep 10.5″ PA 51 degrees. Brilliant getting it back then, think I only had a 60mm refractor back in the 70’s and no I didn’t see it with that 🙂
Andrew
I note the author did not answer Owen’s question on the source of the ‘credible observations’ but simply removed the word credible from the article. You never said John whether or not you had observed the pup yourself, I would like to think you had before writing such an article and suggesting or implying what aperture scope it might be visible in from UK skies.
Andrew
I would concur Peter. I have been observing double stars for about 30 years now using a variety of high quality, high contrast telescopes including a 7″ F8 Mak-Newt with 1/10th wave quartz optics and 13% obstruction, an 8″ F6 Mak-Newt with 18% obstruction, 1/9th wave astro sitall optics and an OMC 200 Mak-Cas, F20, 4,000mm FL with 22% obstruction. I’ve failed to see it in all of those scopes despite numerous attempts. I have seen it twice in my Takahashi Mewlon 300, a 12″ high contrast Dall-Kirkham design and once in my 18″ F4.5 Newtonian which has a superb mirror. The first time in the Mewlon was back in October 2007 when it was just below 8″ separation. The seeing was excellent, the E & F stars in the trapezium stood out like there was always 6 on show but even so, the pup was just momentary glimpses in the glare of Sirius A but consistent in it’s position. A check the next day confirmed I had the correct PA. The next time was a couple of years later in the 18″ at Kelling Heath. Skies were claggy but seeing good so I changed my targets. Again the E & F stars stood out so I gave Sirius a go but first being a Dobsonian which always has some flexure I collimated the scope for that altitude. The observation was similar to that I’d had with the Mewlon previously. Then last month in the Mewlon, again E & F stars steady and tight (I think this is a pre-requisite in my book – if you can’t see them well, don’t even bother going for Sirius B). This time of course the seperation is 11″ and I had an almost continuous view of the pup for about half an hour, a faint spec just below the diffraction spike from the spider. Even so the pup was very faint and almost averted vision in the glare of Sirius B. It’s altitude in the UK does not help, even when the seeing is very good high up, it rarely is at the altitude of Sirius. I know an occulting bar would help but for me the beauty of observing this is seeing it against the glare of the primary and not in isolation.
Andrew
My sketch from this morning attached. Location Haw Wood, Suffolk, 18″ F4.5 Dobsonian, 13mm Ethos e/p, x160.Thanks to Owen for alerting me (I had no e-mail) and Nick for the latest accurate co-ordinates.
Andrew
Hi Callum,
Thanks for your reply. I do understand the difficulty with bookings especially when using educational establishments for venues. I mention it merely as a reminder to avoid conflict wherever possible. The original date for the Winchester w/e was fine but I know you had to change it through no fault of your own so no problem. March 23rd for the DSS meeting is fine – full moon is on the 21st. As Owen points out I will miss this and Kelling in April 2019 anyway as I’ll be in New Zealand – I’ve booked two new moon periods to maximise my chances of seeing the Southern constellations/stars (I’ve never seen the LMC, SMC, Eta Carina or 47 Tuc – will be taking a travel scope with me.) It will be the first Kelling I’ve missed ever but hopefully will be well worth it. Ironically I would have been back in time for the original Winchester date.
Re September, this is the one to avoid a new moon event if possible. The Autumn Kelling is invariably over the new moon period in September. About once every 4 years it occurs in the first week in September and occasionally gets pushed into October to avoid school holidays, this year was a close call.
Regards, Andrew
Had another good visual view last night. I reckon it’s dropped by about a magnitude from previous night.
Observed it with my 12″ D-K Mewlon and my large 28 x 110 binoculars. It was just detectable in the 11 x 70 finder. It was distinctly reddish in the 12″ but too small a FOV to make magnitude comparisons. The best overall view was in the 28 x 110 binoculars which I used to make magnitude estimates.
2nd May 2018, 21:30 hrs UT:Now dimmer than SAO 39696 (mag 7.97) but brighter than SAO 39704 (mag 9.3) In a ratio of 4 parts I put it -1 and +3 roughly = mag 8.3. Looked slightly brighter than SAO 39710 (mag 8.77) but midway between SAO 39734 (mag 8.88) and SAO 39742 (mag 8.14) which equates to approx mag 8.5. I would plum for mag 8.5.Forecast looking good for the weekend so an opportunity to see this plummeting each night, it will soon be fainter than the mag 9.33 star next to it. Great stuff.
Andrew
I had visuals on it last night from 22:15 hours to 23:15 hours. It was a balancing act between the sky getting darker as astro dark approached (22:58) but getting brighter as the almost full moon rose higher (moonrise 21:52) combined with target getting lower! I first detected it (surprisingly) in 7 x 50 binoculars just getting to grips with the field as I was going to use small fully manual scopes on Alt-Az mounts so I could move around to clear horizon obstacles. I then switched to a 72mm ED with full erecting prism and various powers starting off with a 24mm Panoptic giving x18 with a 3.8 deg FOV. I then switched to an Intes-Micro Alter 500 127mm F10 Mak-Cass for more light gathering. I didn’t see the mag 9.3 star (SAO39704) very near to it in the bins but I did in the 72mm and 127mm scopes. It was much brighter than the mag 9.3 star and I thought it had a hint of a red tint to it but very difficult to be sure on faint-ish objects. I then compared it to nearby stars SAO 39724 (mag 7.26) and SAO 39696 (mag 7.97), these were the two stars at the bottom of the Rhombus pattern. It wasn’t quite as bright as the m7.26 star but brighter than the 7.97, I put it at a 1/3 to 2/3 so estimated the brightness of V392 at mag 7.50.
Great fun, Andrew
Thanks for the alert Gary. Typical however, we’ve had loads of rain here in East Anglia in the last few days and still raining. If it does stop we’ll still have a full moon to take the edge off. Hopefully it will still be shining promnently when conditions improve.
Andrew
Nick, I did get another visual about 3am this morning with the 24″. Unbelievably conditions were even better than the previous morning with SQM readings of 21.52 and glimpsing M13 N/E. So this time I could split it with a 13mm Ethos (x208) but still much clearer with 8mm (x340). The 4.7mm Ethos (x575) didn’t improve the view just seperated core and SN more but at the expense of crispness due to seeing conditions. I would still say it’s white to off-white and brighter than the core. If really pushed I would say a hint of greenish-blue along the lines of planetary nebula but this probably a combination of imagination because I was looking for any colour and that faint objects (relatively) always having a tendecy of being gray or ‘bluish’ to me. Andrew
No colour seen Nick but I’m never particularly good at detecting colour in DSO’s so doesn’t mean it’s not there to be seen. I’ll have another look tonight, all set up and off out now.
Andrew
Yes, thanks to Owen’s alert I got a visual on it this morning with my driven 24″ Dobsonian and managed a sketch. I had to go up to an 8mm Ethos e/p (x340) to seperate the SN from the core. I found the SN to be brighter than the core. I didn’t see as much of the outer halo as you captured in your image Nick. Skies were excellent with SQM readings of 21.44 in direction of target and a NELM of 5.8 to my old eyes. Seeing about ant III.
I was at Kelling Heath and had 3 clear nights in a row on the Thur/Fri/Sat. Very poor display this year, only saw a handful, most in the early hours of Friday morning (17th) but did see a leonid fireball in the early hours of Sunday morning. I was facing the opposite direction and thought a car headlight was driving onto the field, turned around in time to see it brighten then explode. Must have been at least mag -10 as far brighter than the brightest irridium flare which can reach about -8. Left a trail about 2 degrees long which lasted for about 10 seconds – Brilliant! Gain Lee saw it also.
Andrew
I just typed a long reply, hit the wrong key by accident and lost it all! Can’t type it all out again – too slow! But basically I reckon East Anglia, in particular Suffolk and Norfolk has the best of it. I live 12 miles West of Lowestoft. Near RSPB Minismere is good.
Andrew
Hi Nick,
I did try and reply to Gary’s comment (but we had a thunderstorm and my internet went down) to say, ‘agree with Gary and of course what Andrew does is Astronomy and in fact making pretty good use of his skies as you yourself do Nick. I just thought Woolley’s comments was a good take on my pretty much minority pursuit these days. And of course you are a lot more productive than me. I fully accept I’m the dinosaur here.
Andrew
Andrew
Well his comments are certainly my take on amateur astronomy. I enjoy being under the stars and actually enjoy looking at the stars wether naked eye or through the telescope (I know that’s a rare thing in these days of imaging everything). And yes I hardly ever pack up observing whilst it’s stll dark and clear, would consider myself a lightweight otherwise – have to make the best of any clear window in this country.
Andrew Robertson
I managed a brief 5 minute visual view of it last night in my 12” F5 ultra-portable dob from Norfolk. It had been clear all evening and forecast to be clear most of the night but with a bit of cloud coming over early on. Issues were; Nautical dark commencing at 22:25 hrs, astronomical dark at 23:58 hrs and a 86% mon rising at 23:48 hrs. I decided about 23:30 hrs would be about the best time to get on it and had the scope set up by 22:30 hrs in preparation doing a few lollipops (M13, M5, M92 etc.) as a warm up. However shortly before 11pm I saw a cloud front slowly moving over from the SSW so thought I ‘d best have a look sooner. I found ngc 6939 easily enough but ngc 6946 was just detectable, a combination of it’s a low SB and a far from fully dark sky. I used the image by Wiggins (Owen Brazell had posted a link on the Webb Soc forum) to identify the star fields. I had a fully inverted view and quickly recognised that triangle of brightish stars just ‘above’ 6946. I was then looking for those two pairs of stars below 6946 but initially just noticed the brighter pair lower down. Another look at the image and I recognised the field. Had started off with a 24mm panoptic giving x62 but changed to a 13mm T6 Nagler giving x115. Going back to the eyepiece I then located the two pairs of stars. They were very faint in that relatively brightish sky but were direct vision – just! The pair with SN were slightly brighter than the other pair. I enjoyed the view for about 5 mins before the cloud came over. As I got my eye in, the SN became quite obvious. It did clear again but only just after the moon had risen.Very enjoyable,
Andrew Robertson
