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Though astronomers have discovered thousands of planets orbiting other stars, very little is known about how they are born. The conventional wisdom is that planets coagulate inside a vast disk of gas and dust encircling newborn stars. But the details of the process are not well understood because it takes millions of years to happen as the disk undergoes numerous changes until it finally dissipates.

The young, nearby star AU Microscopii (AU Mic) is an ideal candidate to get a snapshot of planet birthing because the disk is tilted nearly edge on to our view from Earth. This very oblique perspective offers an opportunity to see structure in the disk that otherwise might go unnoticed. Astronomers are surprised to uncover fast-moving, wave-like features embedded in the disk that are unlike anything ever observed, or even predicted. Whatever they are, these ripples are moving at 22,000 miles per hour – fast enough to escape the star's gravitational pull. This parade of blob-like features stretches farther from the star than Pluto is from our sun. They are so mysterious it's not known if they are somehow associated with planet formation, or some unimagined, bizarre activity inside the disk.

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      Media Contacts
      Laura Betz – laura.e.betz@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Matthew Brown – mabrown@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
      Christine Pulliam – cpulliam@stsci.edu
      Space Telescope Science Institute, Baltimore, Md.
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      Last Updated Mar 10, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
      James Webb Space Telescope (JWST) Astrophysics Brown Dwarfs Goddard Space Flight Center Science & Research Star-forming Nebulae The Universe View the full article
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