American Association of Variable Star Observers (AAVSO)
Wed, 12/12/2018 - 22:36

This isn't a well observed star with only 24 observations in the past 2 years. 

It's right next to T Ori which is well observed, almost 2,800 observations in the past 2 years. 

Any reason observers are looking at one and not the other? 

Both stars are a bit of a challange as they both sit behind the same nebulosity from the Trapezium. 


American Association of Variable Star Observers (AAVSO)
I will pick it up...

I observe T ORI this time of year as often as possible.  I'm familiar with the star but didn't know it was variable. M42 is such a rich field for YSOs!

Ori comparison stars

Because the Orion nebula is our nearest star-forming region, it contains lots of new stars, many of which have not yet reached the Main Sequence, and most of which vary in an irregular fashion.  The hard part is to find non-variable stars to use as comparison stars!  Visual observers have it a bit easier, because many of the variables change by less than 0.1mag and could be used as visual sequence stars.  However, the sequence team generally avoids these low-amplitude variables, and so the sequences you find in this field may be more limited than elsewhere.  The nebulosity interferes as well, both due to the bright background it contributes as well as in obscuring background stars that could be used.  It is a very interesting area to study!

There are often more than one variable in a field that observers could measure and submit, not just in Orion.  Multiple clusters have several eclipsing binaries or pulsating stars, for example.  Limited submissions could be due to ignorance of the other variable or lack of a good sequence for its magnitude range.  That said, it is an efficient use of your time to report on these secondary targets.

I remember participating on a campaign for V471 Tau, in a similar star-forming region.  The only way I could get a comparison star in my 20arcmin field of view CCD camera was to put the variable in one corner of the field, and then one comp star showed up in the opposite corner.