NASA

Professional alien hunters are starting to investigate the mysterious 'alien megastructure'

It's happening!

JOSH HRALA
27 OCT 2016
 

Astronomers are about to start monitoring the mysterious 'alien megastructure' star - known as Tabby’s star - that we first noticed dimming erratically back in 2015.

The project will monitor the star using the 100-metre-wide (330-feet-wide) Green Bank Telescope in West Virginia, searching for any potential alien radio signals that could explain its strange behaviour.

 

"The Green Bank Telescope is the largest fully steerable radio telescope on the planet, and it's the largest, most sensitive telescope that's capable of looking at Tabby's star given its position in the sky," said the project’s co-director Andrew Siemion, from the SETI (Search for Extraterrestrial Intelligence) Centre at the University of California, Berkeley.

"We can look at it with greater sensitivity and for a wider range of signal types than any other experiment in the world."

In case you missed it, Tabby’s star – named after the initial study’s author Tabetha Boyajian – made headlines back in 2015 when astronomers noticed that its light dims by 15 to 22 percent for up to 80 days at a time.

Normally, a star might dim by 1 percent every so often, indicating that a planet is likely crossing between it and our telescopes. A drop of 22 percent, though, is unheard of, especially for such a long time period, which caused a debate to flare up as to what could be causing it.

One researcher even suggested that the dimming could be caused by a gigantic alien megastructure – like a Dyson sphere – that might be circling the star 1,500 light-years away from Earth.

Another, more plausible hypothesis is that there's a comet swarm orbiting the star, blocking the starlight in weird patterns, but no one's been able to find evidence to support that, either.

 

Now, SETI researchers hope to finally get to the bottom of the mystery once and for all by making it the first project in the Breakthrough Listen initiative, a US$100 million project funded by internet investor Yuri Milner and Stephen Hawking that aims to search for intelligent life in the cosmos.

It's not the first time the star has been studied.

"Everyone, every SETI program telescope, I mean every astronomer that has any kind of telescope in any wavelength that can see Tabby’s star has looked at it," Milner said.

"It’s been looked at with Hubble, it’s been looked at with Keck, it’s been looked at in the infrared and radio and high energy, and every possible thing you can imagine, including a whole range of SETI experiments. Nothing has been found."

But the new project will be using a much larger radio telescope to effectively 'listen in' to the star and see if they detect any unusual. It's hoped that the additional sensitivity of the Green Bank Telescope could provide brand new insight into Tabby's star.

To perform their new experiment, a team of SETI researchers, including Boyajian, will record 8 hours of observations for three nights over the next two months. During this time, the team plans on recording about 1 petabyte of radio data - that's a whopping 1 million gigabytes.

"The Green Bank Telescope is the largest fully steerable radio telescope on the planet, and it’s the largest, most sensitive telescope that’s capable of looking at Tabby’s star given its position in the sky," Siemion said.

"We’ve deployed a fantastic new SETI instrument that connects to that telescope, that can look at many gigahertz of bandwidth simultaneously and many, many billions of different radio channels all at the same time so we can explore the radio spectrum very, very quickly."

Basically, the team is searching for a signal of intelligent life in different radio signals, much like you search for music stations with a normal radio at home or in the car. Simeon explains in the video below:

Despite many claims about the star, the team has remained sceptical that the unique dimming is caused by an advanced alien civilisation.

"I don’t think it’s very likely – a one in a billion chance or something like that – but nevertheless, we’re going to check it out," said chief scientist Dan Werthimer.

"But I think that ET, if it’s ever discovered, it might be something like that. It’ll be some bizarre thing that somebody finds by accident ... that nobody expected, and then we look more carefully and we say, 'Hey, that’s a civilisation'."

There's no word yet on when the team hopes to have all of their data analysed and published, meaning we’re going to have to be patient before we see any sort of results of the study. Hopefully, though, the project will uncover more details about the star and possibly explain once and for all what's going on around it.

Just last month, researchers suggested that the strange dimming pattern might actually have nothing to do with the star, but interstellar junk between solar systems - so we have still have a lot to learn.

Check out the video below to hear the SETI team talk more about the project:

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