This week we look at V1144Ori. It is situated in what used to be one of our least observed target regions – L1641N in Orion. It is situated just South of the Orion Nebula and thus, our most southerly target region. However, we have now obtained a new number of images from a participant with a telescope conveniently placed in the Atacama dessert in Chile.
The entire target region is full of very interesting objects related to star formation. For example it contains the two first objects in the list of Herbig-Haro objects, jets/outflows from young stars – HH1/2. It also contains the bright reflection nebula NGC1999 (which looks a little bit like a key-hole), surrounding the variable young star V380Ori.
In the light curve we show the B, V, R, and I data obtained roughly during December 2020. The magnitudes have been shifted slightly to improve the visibility of the features. In the literature, the object is known as an Orion variable, indicating it undergoes random variations in brightness. On the long term this might be true. In our short term data we can, however, also see more regular periodic patterns. A quick analysis shows a clear periodicity of 3.5days. This is most likely caused by spots on the surface. Given the larger amplitudes at shorter wavelengths, it seems to be hot spots associated with accretion.
A detailed look shows that the pattern is not strictly periodic, with amplitude variations indicating variable strength of accretion. In particular the peak at JD=2459210 seems to be higher and differently shaped than the others. It will be interesting to see what happens in the new year with this object.