V838 Monocerotis is located 20,000 light years away in the constellation Monoceros. It’s one of the most interesting red variable stars (variable star is a star whose brightness fluctuates as seen from Earth) because at first astronomers thought this was a classic case of a nova but in fact it’s something completely different and to make matters even juicier, they aren’t even sure why! This red star is 5-10 times the mass of our own Sun and has been seen rapidly heating up and expanding in matter of months! This is rarely seen with stars and is telling about how fast this is all happening.