NASA Found a Strange Clock-Like Shadow Around a Distant Star

It’s easy to be hypnotized by the swirling shadow that shrouds TW Hydrae, a young star in massive Hydra constellation.

Scientists at NASA’s Hubble Space Telescope believe the clock-like work of gas and dust around the star might be caused by a nearby planet using its gravitational force to lock in the rotation.

Discovering a new planet is always exciting, especially because they are so difficult to spot in deep space. But Hubble has a bird’s-eye view of this star, and scientists are hoping it reveals a planet between its gaseous layers soon.

The image is a composite of several shots taken by Hubble over the course of a year and is being used to track the rotation of the disc. Scientists found that it moved about 20 degrees, meaning it would take 16 years for the disk to complete a full rotation around TW Hydrae.

“This is the very first disk where we have so many images over such a long period of time, therefore allowing us to see this interesting effect,” said John Debes of the Space Telescope Science Institute in Baltimore, Maryland. “That gives us hope that this shadow phenomenon may be fairly common in young stellar systems.”

When Debes first discovered the unusual brightness surrounding the star in 2005, they began to record it using Hubble’s Imaging Spectrograph, which allows scientists to look as close to the star as Saturn is to our sun, even though it’s 192 light-years away!

Shadow on TW Hydrae's Disk


The more major discovery here is the speed of the rotation. A disk of this magnitude, 41-billion-miles-wide to be exact, would take centuries to orbit the star — 16 years just isn’t long enough.

What they found was that there is a layering effect, multiple disks have formed around the original, and what we are seeing is an offset by one of the inner rings, which is what gives it the asymmetrical look.

NASA scientists say that offset is being caused by the aforementioned planet, which probably rests 100 million miles from TW Hydrae, about as close as Earth is from the sun.

The planet would have to be about the size of Jupiter to have that much leverage over the shadow. The scientists also believe the planet’s gravitational force is pulling the dust and gas up out of the plane of the main disk, causing it to wobble around the star.

The phenomenon will need more research before they can confirm anything. But for now, the findings can lead to a new method for discovering planets in far off solar systems like this one.

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