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RE: LISA mission
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Europe selects grand gravity mission

It is set to be one of the major science projects of the 2030s.
The European Space Agency has just given the green light to the LISA mission to detect gravitational waves.
This will see lasers bounced between three identical satellites separated by 2.5 million km.
By looking for tiny perturbations in these light beams, the trio hope to catch the warping of space-time that is generated by cataclysmic events such as the merger of gargantuan black holes.
Ground-based laboratories in the US have recently begun detecting gravitational waves from coalescing objects that are 20-30 times the mass of our Sun.

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Title: Demonstration of Time Delay Interferometry and Spacecraft Ranging in a Space-based Gravitational Wave Detector using the UF-LISA Interferometry Simulator
Authors: Shawn J. Mitryk, Guido Mueller

Space-based gravitational-wave observatories such as the Laser Interferometer Space Antenna (LISA) use time-shifted and time-scaled linear combinations of differential laser-phase beat signals to cancel the otherwise overwhelming laser frequency noise. Nanosecond timing precision is needed to accurately form these Time-Delay Interferometry (TDI) combinations which defines a ~1 meter requirement on the inter-spacecraft ranging capability. The University of Florida Hardware-in-the-loop LISA Interferometry Simulator (UFLIS) has been used to test Time-Delay Interferometry in a configuration which incorporates variable delays, realistic Doppler shifts, and simulated gravitational-wave signals. The TDI 2.0 combinations are exploited to determine the time-changing delays with nanosecond accuracy using a TDI-ranging reference tone. These variable delays are used in forming the TDI combinations to achieve the LISA interferometry sensitivity resulting from 10 orders of magnitude laser frequency noise cancellation.

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Laser Interferometer Space Antenna
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 Lisa got through to the final run-off in Esa's competition, and then, like Juice and Athena, was forced to modify its architecture to reduce costs when the Americans withdraw their co-operation in April 2011.
As a consequence, Lisa lost one side of its laser triangle and some sensitivity, and was renamed NGO for New Gravitational wave Observatory.

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LISA mission
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Planetary scientists are all set to turn "noise" from the data obtained by NASA/ESA LISA satellites' mission into useful information about the mass of near-Earth asteroids.
LISA is on a mission to detect gravitational waves - a warping of the space/time continuum that scientists hope to see directly for the first time.
Slated for launch no earlier than 2018, LISA will include three satellites connected by laser beams. The distance between the satellites should change as a gravitational wave passes.
Einstein's General Theory of Relativity predicts that gravitational waves from exploding stars or colliding black holes ripple across the universe, causing other bodies to wobble like driftwood in a motorboat's wake.

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