Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 08/03/2020 - 23:52
OBJECT | DATE(UT) | MAG | MAGERR | FILTER | COMMENT
2MASS J00100609+5813196 | 20200802.93 | 14.32 | 0.03 | R |
2MASS J00100609+5813196 | 20200803.91 | 15.67 | 0.05 | R | Lost almost 1.5 mag.
In the data base of variable stars of the ACAC-SN survey, this star is known as ASASSN-V J001006.10+581318.6, type SR with a period of 543.78d and range 15.6-16.2Vmag. But in this case, the star behaved strangely, in one day, it lost almost 1.5mag brightness in the R filter.
Due to the full moon, it was not possible to carry out photometry in filters V and B today.
Nikolay.
This object is a Gaia discovery. I have added it to VSX. Its corrected range is 15.8 - 16.7 in V.
Keep observing it to confirm this fading.
Cheers,
Sebastian
Yes, I will certainly try to observe this star. After all, the loss of brightness per day is almost 1.5mag. the SR star has unusual behavior. This drop in brightness is within the range of brightness variation, but it should occur in half the period (272 d), not one day.
It would be nice if someone else confirmed my observations.
https://asas-sn.osu.edu/variables/dcead603-4105-543f-9a42-416d0efbb543
The star regained its brightness yesterday. The brightness dropped again today. I checked my archive for August 2019. This star did not show such activity and was stable.
OBJECT | DATE(UT) | MAG | MAGERR | FILTER | COMMENT
Gaia DR2 422872584363095808 | 20200804.85 | 14.30 | 0.02 | R |
Gaia DR2 422872584363095808 | 20200805.90 | 15.67 | 0.04 | R | Lost 1.37 mag.
Observations are needed.
For photometry, comparison stars for the MQ Cas can be used.
I have uploaded photometry Gaia DR2 422872584363095808 to the AAVSO database. Very interesting and incomprehensible.
At the moments of the brightness drop, in the V filter, I cannot "get" this star with my equipment. This means that the brightness may fall below the catalog value.
Everything could be explained by the presence of a companion star if it had shown the same behavior last year in August. And during this period I have 9 days of observations from 5 to 31 August.
This star continues its incomprehensible activity. Changes brightness literally every night by almost one and a half magnitudes. It would not be bad to observe the moments of rise and fall of brightness, but this requires observations from different latitudes. Maybe there are people who want to observe this interesting star?
In the next few days, the weather will not allow me to make observations.
Hi Nikolay,
Your observations show a 0.15 mag. scatter at minimum but no changes at all over more than 2 hours around a mean 15.6 Rc (you are using an Rc filter, aren't you?). This is strange because if the star drops 1.3 mag. in less than a day, some change would be expected.
When you observe the star at 1.56 Rc you can't detect in in V, is that correct?
Have you checked your images? These variations do not seem real. Try to rule out any issue with your setup.
I would also consider the possibility of one of the comparison stars being variable (EA) but the fact that you caught so many events in so few observations is too suspicious.
Anyway, can you check survey data on your comparison stars to rule out variability?
Cheers,
Sebastian
I have sent you an e-mail animation for four days in the Rc filter. It can be seen that there is no error. I use comparison stars for MQ Cas (130, 138, 141). Now I am making observations in two filters Rc and V. Today the star is again at its maximum brightness.
I apologize for pointing out the wrong star in the subject line.
I want to clarify. In the V filter I find a star, but because of the full moon for my equipment, it was too weak for high-quality photometry. Now the Moon is not so bright, so I can already do a normal photometry.