In a small galaxy called Holmberg IX (about 12 million light years away), some Astronomers in Ohio have discovered a close binary pair of yellow supergiant stars. Yellow supergiants are rare enough (supergiant stars are unstable when they’re yellow, and tend to turn red or blue), but these two orbit so closely together that they actually share material, forming one big bright peanutty looking object.
This odd fish was discovered as a variable, which on closer inspection turned out to be an eclipsing binary (in case you don’t know, an eclipsing binary is exactly what it sounds like it should be – two stars in a close orbit that periodically eclipse one another causing apparent brightening and dimming). Interestingly enough, it’s not the first one to be discovered, but it is the first to be recognised as such. The team checked through archives and found a similar stellar peanut in the small magellanic cloud, a satellite galaxy of the Milky Way.
A small puzzle might well be solved by the appearance of these weird objects, in that supernovae have been observed, in the past, to come from yellow stars. Yellow stars though, should not have a dense enough iron core to go supernova. However, as a star expands as it turns into a red giant, having such a close neighbour could disrupt the process, causing a buildup of iron, until that critical mass is reached and — KABOOM! Stellar peanut butter!