Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

November 7, 1997
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Evidence for Frame Dragging Black Holes
Drawing Credit & Copyright: J. Bergeron, Sky & Telescope Magazine

Explanation: Gravity can do more than floor you. According to recent measurements of a star system thought to contain a black hole, it can spin you too. This effect, called frame-dragging, is most prominent near massive, fast spinning objects. Now, a team led by W. Cui (MIT) has used the orbiting Rossi X-ray Timing Explorer to search for it near a system thought to contain a black hole. Cui's team claim that matter in this system gets caught up and spun around the black hole at just the rate expected from frame-dragging. Such discoveries help scientists better understand gravity itself.

Tomorrow's picture: Aristarchus' Unbelievable Discoveries

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
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&: Michigan Tech. U.