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iTEL 18 and Vphot gave CG Dra at 16.71 very early this morning.
Check star 147 (14.674 ) estimated at 14.679. Airmass 1.04.
Stewart
IX Dra has been observed by AAVSOnet New Mexico scope, in combination with Vphot, as follows.
2021/07/09 03:45 14.57 V
2021/07/10 04:44 14.7 V
These are values consistent with a superoutburst. There has been a week of no observations so the start of the outburst is not yet clear.
Stewart
iTEL 18 and Vphot report CG Dra, 2459405.55119, 16.693 V filter
So a short outburst that I have just missed. Still all results are useful. iTEL subscription get refreshed on the 12th so will try again.
Stewart
Tim, At the MAST site there is one 27 day photometry measurement for RX And in the TESS data. this record suggests there may be a period of 0.21 days. However there seems to be a lot of short term variation that makes pulling out the 0.21 period really difficult.
MAST is at STScI | Mikulski Archive for Space Telescopes (MAST) Portal
type in “rx and” into the “and enter target” box and hit RETURN. Click on the uppermost “Timeseries Viewer” icon in the second row down. Up pops the photometry record which you can zoom into.
Stewart
Using iTEL 18 (Spain), Vphot gave a V filter mag of 16.86 ( three 300s images stacked) this morning. Stewart
The present superoutburst seems to have been recorded first by Graeme Coates and Tim Haymes on the evening of the 23rd June. This translates to a superoutburst period of 51 +-1 day which is right in the middle of the range of values from 45 to 55 days discussed in VSSC188.
Thanks again to Graeme and Tim and all other contributors.
This target is now really difficult and June has previously marked the end of the observing season. In October the whole cycle begins again with a possible superoutburst around Oct 1. Can this one be observed?
Stewart
I used iTEL 18 last night to get a time series. VPhot reports the V filter magnitude dropping from 13.15 to 13.3 over 13 minutes. The variation may be related to the orbital period of 90 min or the change in skyglow in the dusk sky. Going to repeat tonight but starting a bit later. Stewart
Ken Menzies (AAVSO) has helped me upload images with the clear filter as CV into the AAVSO database. All fit with the existing results from other observers so I seem to have done it right. Stewart
Definitely in outburst and possibly this will trigger the superoutburst. The last superoutburst was recorded, at its brightest at 12.2 visual, by OJR (AAVSO) on 2459339. So we are ~50 days later right now. Could well brighten over the next day or two.
Stewart
ER Uma was at quite dim last night at 15.0 V mag. It is also approaching time for the next superoutburst as the last one started around JD 2459338. With a super outburst period of 55 +_ 5 days, this minimum may be the last before a normal outburst triggers the superoutburst. A few extra observations in the next 5 days could capture the event nicely.
Thanks in advance.
Stewart
IX Dra at 14.6 V mag last night (with distinct variations over 15 minutes) which is typical for superoutbursts. Timing is consistent with expectations as described in VSSC 187. Data is at the AAVSO site.
IX Dra does seem fairly well behaved around its 60.5 days super cycle period.
Only 18.0 V filter last night ( New Mexico AAVSOnet) . Probably the minimum before the superoutburst.
They look good to me. Variation of about 0.15 mag is about right for superhumps, i think. So it all fits.
Thanks , Stewart
V mag 12.4 and 12.88 would suggest a superoutburst has started about 53 days from the previous start.
Jose Ripero Osorio (AAVSO) also reports 12.2 on May 4th.
If anyone can collect time resolved photometry to record super humps that would be good.
Stewart
ER Uma is expected to start a superoutburst shortly (due date May 5th) so if anyone can help with observations that would be great. ER Uma is a reasonably bright target when in outburst, at about V mag 13, and is high in the sky in the evenings during May. Yesterday it was down at Vmag 15 so that may have been the minimum before a rise to superoutburst.
Stewart
According to the recent trend of 60 days between superoutbursts, IX Dra is due to start its next outburst on May 9th – give or take a few days.
Last night it was at V mag 16.7 and the day before at 17.8 (AAVSO BSM-NM). So it may have one more normal outburst before the super starts.
All contributions welcome to try to capture the time of the next superoutburst.
Stewart
