After preparing the figure for this week’s post, I realised it is an old friend of this feature, and we looked at it a few times – most recently in August last year. Nevertheless, 2MASS J20505039+4450115 has a very interesting and unpredictable light curve. Thus, it is always worth to check back after several months, to see what has been happening.

The object sits at the northern edge of the IC5070/Pelican Nebula star forming region. I would like to use this opportunity to remind all the observers that we aim to observe this field in all filters in every night for the entirety of August each year. In particular we are interested in deep Halpha data during those periods, to study long term accretion variability of the stars. So please note this in your diaries 🙂 .

The light curve of the source is showing very long term dimming events, interspersed with shorter term variations. Over the last two years the average brightness of the source has been steadily rising. However, it has still not returned to the bright state it was in ~4.5yr ago, before the first deep dimming started. Also note the occasional very deep and very short dimming event, such as the one visible roughly half way between the two large minima. The two or three data points look like outliers or photometric errors. But they are apparent in all filters and do trace a 2mag dimming event with a duration of less than two weeks.