May 19, 2020 - Science

Listening to a star's heartbeat

Miriam Kramer, author of Space

Artist's illustration of a pulsating Delta Scuti star. Gif: NASA Goddard

Astronomers have found the heartbeat powering a class of pulsating stars in deep space for the first time.

Why it matters: The stellar heartbeats were detected using data from NASA's TESS spacecraft, which is designed to hunt for alien planets circling distant stars. The new discovery shows TESS' versatility and the spacecraft's ability to shed light on more than just far-off worlds.

How it works: Astronomers are able to see pulsations in a star's brightness caused by sound waves bouncing around inside of the star, allowing them to learn more about the star's internal structures, densities and composition.

  • That kind of investigation is difficult with Delta Scuti stars because of their quick rotation, but preplanned observations from TESS allowed scientists to parse out these signals more clearly, tracking a large sample of them.

What they found: TESS data helped astronomers find the patterns of the pulsations being emitted by about 60 of these stars, according to a study published last week in the journal Nature.

  • By clocking the patterns of these pulsing stars, scientists will be able to piece together their ages and other characteristics of the objects.
  • Until now, it was hard to understand the patterns of the stellar heartbeats due to the quick rotation of the stars. They complete a full rotation once or twice per day a dozen times faster than the Sun, according to NASA.
  • "This really is a breakthrough. Now we have a regular series of pulsations for these stars that we can understand and compare with models," Simon Murphy, one of the authors of the new study said in a statement.

Go deeper: Hear the heartbeat of a Delta Scuti star

Go deeper

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