This week we have a look at the young variable star LX Mon. It is situated in the NGC2264 cluster, also known as the Christmas Tree cluster.

In the light curve above we show about 120 days of V, R, and I-band data, from a few years back. The object is classified as a T-Tauri star, and indeed behaves like one. It generally remains constant in its average brightness on year to year time scales. However, in the short term, there are variations of up to one magnitude.

These variations range from short (days) dips to mid-term (weeks) variations. They are typically caused by occultations from disk material and sometimes changes in the mass accretion rate onto the star. The changes in colour in this case hint that most of the variations are due to changing line of sight extinction,i.e. disk material causing the variability.

Note, many of the T-Tauri stars do vary much less – but we tend not to show them as these light curves look quite boring 🙂