This week we have had the first submission of new images for some of the Winter fields. In particular the not so well observed field around the target ASAS-SN-13db, which sits about five degrees west of the Orion nebula in an unremarkable field of stars. This object is an eruptive variable young star – exactly the kind of object our project was set up to investigate in the first place. The start of HOYS coincided with the last major outburst and we managed to observe the star during the last half year of the burst all the way back to its normal brightness. Indeed this object was the focus of the first ever paper using data from HOYS – The 2014-2017 outburst of the young star ASASSN-13db. A time-resolved picture of a very-low-mass star between EXors and FUors.

In the light curve we show the I-band magnitude of the star. As one can see, the brightness has dropped by about 3.5mag since the peak and remained at 16-17mag since. The variation since is what we usually see from many young stars. Prior to the 2014-17 burst, the object had a much shorter, less strong eruption in 2013. This kind of behaviour is usually classified as EX-Ori outburst – interestingly named after the prototype EX-Lupi (the reasons for this confusing naming is a whole other story). So the object could have another outburst at some stage.

It is always interesting to observe these objects as soon s they are appearing again from behind the Sun to see if they have changed. Indeed, as mentioned above, we have some new data for the source now. Unfortunately no I-Band data, and the images in the other filters are not deep enough to measure the brightness. However, looking at the images in detail, we can at least say the object has not increased by more than one magnitude from its normal brightness. But keep en eye on his field every few weeks to see if things change…..