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T05 New Mexico gave 17.27 this morning at 2459222.01.
So still in a low state. Graeme Coates measured it at 16.0 on the 5th which may have been the peak of the last normal outburst. So that may mean another 3 days wait.
Sorry Robin : DSS? I’m too new to this topic
I did get an image at 5:30am local from New Mexico and estimate V mag 17.1 +_0.33.
So we seem to observed a normal outburst at mag 16 on the 5th at 2459220.29 recorded by Graeme Coates.
Stewart
I am on a couple telescopes in New Mexico in few hours time. Had no luck with itel Spain owing to “roof closed”: clouded out.
Stewart
I also got Mag 15 on Jan4 from New Mexico AAVSO BSM NM2.
The only TESS record happens to show the approach to a superoutburst. The normal outbursts are ‘peaky’ or ‘trianglular’ at least compared to IX Da and RZ Lmi.
Last night’s result from AAVSOnet gave a V Mag of 13.5. Er Uma has displayed a series of gradually more intense normal outbursts. It is now 40 days since the start of the last superoutburst.
With a supercycle length of around 45-50 days in the present epoch the next superoutburst may occur shortly. The graph below shows how the supercycle period has varied over the last 200 cycles (27 years).
Previous superoutbursts have reached Mag 12.5.
Stewart
The next superoutburst is expected in the first half of January.
IX Dra is now quite a difficult object for the USA based AAVSOnet telescopes that I have been able to use so far, although a couple of AAVSO observers ( Sweden and Virginia, USA) do seem to have reasonable northerly aspects and continue to report. AAVSOnet SRO Arizona is out of service at this time with a failed camera.
UK observers benefit from their higher latitude compared to the USA, but IX Dra has a very low elevation at this time of year.
If anyone can help for the period from Jan 1st to Jan 15th to capture the start of the superoutburst it would be appreciated. The most likely date for the start is in the middle of the window above – with the usual uncertainties.
Stewart
ER Uma was at 14.7 last night down from 12.8 at maximum 13 days ago. So that superoutburst has been completed. The superoutburst period is around 40-50 days so about this time next month could be the next one.
RZ Lmi is in quiescence following a normal outburst on 3 Dec. The next superoutburst is due shortly as its super period is only about 20 days.
I was taught in Angstrom but adapted to nm in my professional life. You get used to anything in the end.
Stewart
The November superoutburst is over, a return to quiescence at mag 17 and then a rise to 15.9 has been reported by AAVSO observers.
RZ Lmi was 14.26 at 2020/11/24 11:06:56 UT
ER Uma was at 12.8 at 2020/11/24 11:13:38 UT
Both were measured using AAVSOnet.
SRO telescope , Arizona gave 15.3 at 1:33:8.35 UT on November 16, 2020.
Those recorded by TESS were about 10 days in duration from when the first superhumps appeared to getting back to quiescence at mag 17.
Stewart
IX Dra has been interesting for a newcomer like myself. It changes every five days or so and puts in a bright superoutburst fairly regularly. Following IX Dra might be a good New Years resolution.
I am going to follow ( from my desk as I do not have my own telescope) other UGER stars that are high in the morning sky: ER Uma, RZ Lmi, and DI Uma and are starting their observing season. These are also evolving fast enough to be rewarding. Gary Poyner recommended RZ Lmi as it is a good winter target and it has a superoutburst every ~20 days so there really is something happening every few days.
Stewart
The anticipated superoutburst has been detected. Superhumps are confirmed. I estimate the outburst started at 2459162.5 and should continue for another 10 days or so. I have updated the graph and hope it is fully inclusive for all those have contributed.
The timing of this superoutburst gives an average period for the last 8 outbursts of 59.5 days. This value is close to the last reported value of 58.5+-0.5 from 2010 and suggests that the super outburst period has not really changed in ten years. I will stick my neck out and suggest that the next outburst will start near January 7th.
I think this has been a worthwhile exercise and would wish to thank all who have contributed.
Regards
Stewart Bean
ASAS-SN reports IX Dra at magnitude 15.6 in its green channel for 2459162.6 : so back to a high state. When in superoutburst ASAS-SN has recorded magnitudes in the 14.5 to 15 range.
The UK weather forecast seems a bit Novemberish with cloud on all days this week for Cambridgeshire. Fortunately, there is good weather forecast for the AAVSOnet SRO, Arizona telescope for the week ahead.
I’ll keep you posted.
Stewart
The AAVSOnet SRO telescope in Arizona suggested a V mag of 17.7 last night – so a low state.
One week to 10 days to go before the super outburst.
Regards
Stewart
The V filter observations graph below shows the current status as we approach an expected superoutburst in roughly two weeks time. With the frequency of observations achieved during this campaign, it should be possible to time the the superoutburst to within one day. This in turn should allow a fairly precise value for the superoutburst period to compare with literature values. The literature graph below implies a supercycle length of about 65 days for 2020 whilst TESS results, from 2019, suggest 61 days.
The observations below may not be complete so apologies in advance. Six normal outbursts at 5 day intervals have been recorded. The superoutburst is expected to reach 14.5 during November.
Thanks to all contributing.
Today I noticed the graphs had gone from my posts . I have put the latest back into the 26th Oct post. Any thoughts on the reasons? Are some formats preferred?
Nick James, Gary Poyner and David Swan all report IX Dra at fainter than 17 over the weekend. So back to its low state for a day or so. We can expect a few more normal outbursts at 4-5 day intervals before the super outburst around Nov 14th ( I’m sticking my neck out a bit here, I know).
Stewart
Thanks . That fits with the normal outbursts being about 5 days apart before a superoutburst. In the attachment from TESS data you can see the normal outbursts become more intense and 4-5 days separation. IX Dra never really goes into quiescence. StewartThe graph summaries the results to date.
There seem to have been three normal outbursts at 3-5 day intervals reaching 16.5 magnitude (V) at peak. The project is trying to time the next superoutburst to check the apparently regular 61+-2 day period suggested by TESS results. The next superoutburst is likely in the middle of November. If we can maintain observations at this frequency then we will have an uncertainly of only a day of two. Thanks to all observers who have contributed. Bean data is courtesy of AAVSOnet.
Stewart and Jeremy
