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Salyk said she was familiar with the activity surrounding this star because it had previously been captured by a telescope at the Keck Observatory in Hawaii. “I had observed this source at other wavelengths,” she explained, “so I was brought in as an expert to discuss the properties of this source and how it’s similar to or different from other protoplanetary disks that have been observed with Keck.”

Salyk is a co-author of a paper explaining this curious phenomenon that will be published in Astrophysical Journal, a leading astronomical publication. The lead author of the paper is Klaus Pontoppidan, an astronomer at the Space Telescope Science Institute in Baltimore, MD. “The shadow moves. It’s flapping like the wings of a bird!” said Pontoppidan. He said the phenomenon may be caused by a planet pulling on the disk and warping it.

This disk casts one of the largest known shadows, and it’s the only one known to “flap its wings,” Salyk said, adding that the shadow the disk casts magnifies small details, enabling astronomers to see something 1,400 light years from Earth that would normally be too small to detect. She said the “flapping” of the shadow provided the team of scientists with two possible scenarios. “Either the disk must have a saddle-like shaped structure with two bumps, which might be caused by a planet’s gravitational influence, or the star is bobbing up and down, which would also be caused by a planet's gravitational influence,” she said.

Sakyk said the team hopes to take more images of the “bat shadow” using the Hubble Space Telescope in the coming months “so we can measure the frequency of the ‘flapping.’” And while this “flapping” has never been seen before, Salyk said she and some of her Vassar students have been involved for several years in searching for other disk motions caused by the planets, using data from the Keck Observatory. Mit Patel ’20 wrote his senior thesis on the topic this spring, and Adam Moses ’21 is working with Salyk this summer under the auspices of Vassar’s Undergraduate Research Summer Institute (URSI). 

Salyk said the images—brought back to Earth by the Hubble Space Telescope, which was launched into low-earth orbit in 1990—continue to provide astronomers with a wealth of new material to study. “What I really like about the Hubble is that it shows you that a really good general-purpose telescope can provide us with images to do cutting-edge work for many years,” she said.

More information about the team’s publication is available on the NASA Hubblesite.