There aren’t many stars like Tabby’s Star lurking in the Milky Way Galaxy. Hell, astronomers have never seen anything like it. Formally designated as KIC 8462852, the star made headlines after observations from the Kepler Space Telescope showed significant dimming.
Kepler is always on the hunt for dimming caused by planets moving in front of its host star, but this was something different. On one occasion, the star’s light output plunged roughly 20%. Astronomers hunting for exoplanets are always on the lookout for dips in brightness, but usually exoplanets only cause a dip of a couple of percent at the most. Not 20. That suggests something massive is passing in front of the star.
Here are the light curves from some of the first Kepler exoplanet discoveries. See how only the biggest planet caused a dip of one percent. The others were around a half percent or less.
Astronomers have struggled to explain what’s going on with Tabby’s Star. But that could be about to change.
ALERT:@tsboyajian‘s star is dipping
This is not a drill.
Astro tweeps on telescopes in the next 48 hours: spectra please!
— Jason Wright (@Astro_Wright) May 19, 2017
Astronomer Jason Wright called on telescopes from around the world to focus on the star in the hopes of cracking its mystery. When the star first made the news, Wright’s suggestion that the strange dimming could be the result of an alien megastructure grabbed the headlines. Wright was pointing out just how stumped astronomers are about the star.
SETI sat down to chat with Wright after Tabby’s Star started dimming again yesterday. Give it a watch to learn more.
Spectra data could help them solve the mystery
Multiple observatories spent Friday night watching the latest dimming happen in real time. These observations also include the all-important spectra data. If astronomers are going to figure out what’s going on, it’s with this data. Spectra data shows the light output in a variety of wavelengths.
Say if the data shows high absorption in blue and ultraviolet wavelengths. That would lead scientists to believe there’s a huge cloud of dust causing the dimming. Extra infrared radiation would point the finger at a family of comets.
As for an advanced alien civilization building stuff around their sun? It makes for a good headline, but we won’t see any evidence of that. Not this weekend. Still, Tabby’s Star is unlike anything we’ve seen so far. Real-time observations might give the answers astronomers have been looking for since first discovering the weird dimming. Or, it could raise even more questions.
Yesterday, the star was dimming by 2%.
— Tabetha Boyajian (@tsboyajian) May 19, 2017
Not the 20% seen before, but it could be just the beginning. Telescopes positioned around the world will keep watching the star to see how long this event lasts.