February 10, 2011 - Astronomy Now
Jupiter's impressive 2009 scar, which was first spotted by amateur astronomer Anthony Wesley, was likely created by an asteroid the size of the Titanic cruise liner, say scientists who studied the aftermath of the collision.
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A dark black marking was observed visually on the giant planet on 19 July 2009 by Anthony Wesley, who alerted professional astronomers around the world. Follow-up observations from NASA's Infrared Telescope Facility in Mauna Kea, the Gemini North and South telescopes, ESO's Very Large Telescope and even the Hubble Space Telescope in the week after, enabled astronomers to observe the warm temperatures and chemical reactions caused by the impact.
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