Could there be another mysteriously dimming star in our galaxy?
Another cosmic mystery has been discovered in our vast universe. A nearby star was caught dimming, but that isn’t what caught our attention. It was the fact that the star, named EPIC 204376071, dimmed by up to 80%. This event surpasses the dramatic dimming of the Boyajian’s star also known as Tabby’s star when it dimmed by 22%. However, EPIC 204376071 gets even more interesting. This particular star did not only dim quite suddenly, hitting a record of 80%, it also brightened again as if whatever was blocking the light from reaching Earth moved on.
The New Star
EPIC 204376071 is a red dwarf, which makes it quite different from the Sun. It’s only about 16% of the Sun’s mass but around 63% of the Sun’s size. The star is dim, according to the researchers it is only 3% as luminous as the Sun and has an effective temperature of around 3,000 Kelvin. For comparison, the Sun’s temperature is around 5,777 Kelvin. This star has turned out pretty strange based on these results. It’s small, it’s dim, it has a low mass, and it has a low temperature.
It’s also been classified pretty young for a star, only around 10 million years old. However, these are all typical characteristics of a red dwarf which should mean that this star isn’t too strange, right? Well, EPIC 204376071 may be hiding a few secrets. One of these secrets centers around why the star suddenly dimmed by 80% before returning to normal and researchers are determined to find out why.
What Could Be The Cause?
There are a few explanations for why this new star suddenly dimmed as if something passed in front of it. The asymmetric dip in light and the age of the star led researchers to consider two different scenarios; either the star is orbited by dusty material that blocked the light (called the dust sheet model), or the mysterious dip was caused by the dusty disk of an orbiting ringed planet. Both scenarios can explain the feature, but they still don’t seem to fit. Having dust material orbiting around the star like a sheet seemed unlikely to the researchers especially since the star is only 10 million years old. At that age, it would still be absorbing material for its neighborhood. So, this could have just been a one-time event.
In terms of the ringed planet scenario, the team expected the dusty disk to have a diameter of at least 4.2 times the radius of the host star. The planet that hosts the ring would have to be about three times the mass of Jupiter and the ring itself would need to be roughly the same size as Saturn’s. The problem with this scenario is that the timing of the object doesn’t match up. The model called for an orbital period of 28 days at a distance of around 10% of that between Earth and the Sun, but the event was only observed once in 160 days. This could only mean that whatever is orbiting the star can’t have an orbital period shorter than 80 days.
Just Another Mystery
Both scenarios created a small dilemma for the research team. One didn’t make sense due to the age of the star while the other didn’t match up with the model the team created. This star may end up being just another mystery that may never be solved. Although the last option is not entirely impossible, it was still very unlikely. Nothing seems to fit when it comes to EPIC 204376071, it seems to be set apart from the other stars we have discovered. The research team doesn’t expect the star to be studied again in any planned short- or medium-term planet-hunting campaigns. It all comes down to the funding and whether EPIC 204376071 will get a chance in the spotlight or if it will fade into the background like so many other stars did before it.