AU Microscopii 2018 Detail

Hubble Captures Intricate Structures Inside a Giant Migrating Blob

The Hubble Space Telescope image on the left is an edge-on view of a portion of a vast debris disk around the young, nearby red dwarf star AU Microscopii (AU Mic). Though planets may have already formed in the disk, Hubble is tracking the movement of several huge blobs of material that could be "snowplowing" remaining debris out of the system, including comets and asteroids.

The box in the image at left highlights one blob of material extending above and below the disk. Hubble's Space Telescope Imaging Spectrograph (STIS) took the picture in 2018, in visible light. The glare of the star, located at the center of the disk, has been blocked out by the STIS coronagraph so that astronomers can see more structure in the disk.

The STIS close-up image at right reveals, for the first time, details in the blobby material, including a loop-like structure and a mushroom-shaped cap. Astronomers expect the train of blobs to clear out the disk within only 1.5 million years. The consequences are that any rocky planets could be left bone-dry and lifeless, because comets and asteroids will no longer be available to glaze the planets with water or organic compounds.

AU Mic is approximately 23 million years old. The system resides 32 light-years away in the southern constellation Microscopium.