Skip to comments.Asteroid Nudged by Sunlight: Most Precise Measurement of Yarkovsky Effect
Posted on 05/28/2012 7:48:18 PM PDT by SunkenCiv
Scientists on NASA's asteroid sample return mission, Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx), have measured the orbit of their destination asteroid, 1999 RQ36, with such accuracy they were able to directly measure the drift resulting from a subtle but important force called the Yarkovsky effect -- the slight push created when the asteroid absorbs sunlight and re-emits that energy as heat...
Observations that Michael Nolan at Arecibo Observatory in Puerto Rico made in September 2011, along with Arecibo and Goldstone radar observations made in 1999 and 2005, when 1999 RQ36 passed much closer to Earth, show that the asteroid has deviated from its gravity-ruled orbit by roughly 100 miles, or 160 kilometers, in the last 12 years, a deviation caused by the Yarkovsky effect...
"The Yarkovsky force on 1999 RQ36 at its peak, when the asteroid is nearest the sun, is only about a half ounce -- about the weight of three grapes on Earth. Meanwhile, the mass of the asteroid is estimated to be about 68 million tons. You need extremely precise measurements over a fairly long time span to see something so slight acting on something so huge."
Nolan and his team measured the distance between the Arecibo Observatory and 1999 RQ36 to an accuracy of 300 meters, or about a fifth of a mile, when the asteroid was 30 million kilometers, or 20 million miles, from Earth.
(Excerpt) Read more at sciencedaily.com ...
artist concept of OSIRIS-REx Artist concept of OSIRIS-REx. (Credit: NASA/Goddard/University of Arizona)
Thanks go out to the Mods for pulling the duplicate. Beats me how that happened, I’ve had it go medieval on my ass about four times today.
They are finally getting tired of blaming everything on Bush.
Cool. But I wish scientists would stop mentioning imperial units and confuse the story.
Don't hijack the thread. Especially through passively pushing metric units, which are irrelevent in the days of computers - but serve liberal cultural sabotage intentions in America.
Thanks so much for playing. Come again real soon now, hear?
Uhhhhh....thank you for the comment....?
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