This week we look at V591Ori. This is another of the young stars situated in the L1641N cloud in Orion.

At a distance of 293pc, this objects is relatively nearby, as are several of the young stars in that target area. The object is known as an Orion variable, indicating seemingly random brightness variations. As the object is near the ‘edge’ of the field, i.e. it lies outside most of the very few images of this field that have been submitted to our database, we do not have any long term data.

However, the newly submitted data shown in the light curve indicate that the source exhibits clear periodic variability in all filters. The period of the variations is about six days. Amplitudes are larger at shorter, bluer wavelength, thus indicating hot/warm spots on the surface of the young star. These could be caused my mass accretion columns onto the surface, that move in and out of view with the rotation of the star.

A detailed look at the light curve also shows that the amplitudes and shape of the magnitudes in each period do differ slightly. This indicates potential variability in the mass accretion rate and the position of the accretion column. One of the objectives of an ongoing PhD thesis is to investigate these variations statistically using our HOYS data. Stay tuned for more detail on this in the future.