Gravitational Waves & Neutron Stars/Black Holes: Observed Velocity Decrease

Rorkster2
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2 closely orbiting massive objects are predicted to deserve the fabric of spacetime so much that they will release a ripple of gravitational waves. When geavitational waves are released, they slowly loose velocity energy and spiral into one another. 2 pulsars were discovered orbiting each other which prompted a Nobel Prize being awarded in 1993.

My question is have we measured decreasing velocity between 2 massive objects in a tight orbit or have we observed them spiraling into one another, which is then attributed to velocity reduction through releasing gravitational waves?
 
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What was observed in the Hulse-Taylor binary pulsar was a decrease in the orbital period. See the "Binary Pulsar" entry in Wikipedia.
 
If two orbiting objects lose energy, their velocity increases. At least in theory, it should be possible to observe their velocity via the doppler effect. Maybe this was done, check the publications.

Edit: Oh wait, of course they measured the velocity - it is necessary to measure the orbital period.
 
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http://www.lightandmatter.com/html_books/genrel/ch09/ch09.html#Section9.2
 
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