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Using Quasars to Measure the Earth: A Brief History of VLBI

VLBI, or Very Long Baseline Interferometry, is a technique that uses multiple radio telescopes to very precisely measure the Earth's orientation. It was originally invented back in the 1960s to take better pictures of quasars, but scientists soon found out that if you threw the process in reverse, you could measure how the ground beneath the telescopes moves around, how long days really are, and how the Earth wobbles on its axis as it revolves around the sun! Learn more about VLBI here!

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Credits

Chris Smith (HTSI): Lead Animator
Chris Smith (HTSI): Video Editor
Steven J. Wall (MUNIZ): Narrator
Chris Smith (HTSI): Producer
Chopo Ma (NASA/GSFc): Scientist
Chris Smith (HTSI): Writer
Please give credit for this item to:
NASA/Goddard Space Flight Center

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Narrated Movies

Goddard TV Tape:
G2012-060 -- Using Quasars to Measure the Earth: A Brief History of VLBI

Keywords:
SVS >> Earth
SVS >> HDTV
SVS >> Music
SVS >> Quasar
SVS >> Edited Feature
SVS >> Interview
DLESE >> Narrated
SVS >> Radio Telescope
SVS >> Geodesy
NASA Science >> Earth
NASA Science >> Universe
SVS >> VLBI
SVS >> Very Long Baseline Interferometry