ESA Plans Space-Based Observatory to Detect Gravitational Waves

Thursday, 09 June 2016 - 11:32AM
Space
Astrophysics
Physics
Thursday, 09 June 2016 - 11:32AM
ESA Plans Space-Based Observatory to Detect Gravitational Waves
One small step closer to detecting gravitational space waves for man... one giant leap for mankind and all of physics. The European Space Agency has successfully tested a key technology needed to build a space-based observatory for detecting gravitational waves. 

Last we heard of gravitational waves a few months ago, physicists from LIGO (the Laser Interferometer Gravitational Wave Observatory) were just confirming their discovery. In case you need a refresher course, these waves are ripples in the fabric of spacetime caused by super-energetic events in space, like supernovae and black hole mergers. 

But seismic, thermal, and other noise sources limit LIGO to higher-frequency gravitational waves, i.e. those around 100 cycles per second. Finding signals from more exotic events like supermassive black holes in colliding galaxies requires the ability to see frequencies at 1 cycle per second or less - a sensitivity level only possible from space. 

A space-based observatory would work by tracking the test masses that move only under the influence of gravity. Each spacecraft would gently fly around its test masses without disturbing them, in a process known as drag-free flight. 

Enter ESA's LISA Pathfinder mission - whose primary goal is to test the current technology by flying around an identical pair of 1.8 inch gold-platinum cubes. The gold-platinum alloy was chosen for its high density and insensitivity to magnetic fields.

Opening quote
"LISA bridges the gap in gravitational wave frequency between pulsar timing arrays and LIGO so it is absolutely critical if we are to characterize the full gravitational wave spectrum," West Virginia University's gravitational wave scientist Maura Mclaughlin said in a statement.
Closing quote


Although it is a space-based interferometer, LISA Pathfinder isn't designed to actually detect gravitational waves, but rather as a prototype observatory to test the detector technologies needed for the full-blown LISA mission. 

Finally, the results of the LISA Pathfinder mission are in, and scientists say they are nothing short of astonishing. Non-gravitational forces on the cubes were reduced to levels far below the project's original requirements and approach the level of control needed for a full-scale observatory. The two cubes were in free fall and almost motionless with each other, and scientist were able to determine the distance to less than the diameter of an atom - an accuracy level that was five times higher than the goal. 

Opening quote
"LISA Pathfinder was always intended as a stepping stone to the level of performance needed for a full-scale gravitational wave observatory, but these results tell ups we've nearly made the dull jump. A full scale observatory with LISA Pathfinder's performance would archive essentially all of the ultimate science goals," said Ira Thorpe, a member of NASA's Goddard Space Flight Center.
Closing quote


The full LISA mission will consist of three spacecrafts in a triangular configuration, each containing two gold-platinum cubes in free fall, and is expected to launch in 2034.

Via The Verge

Science
ESA
Space
Astrophysics
Physics

Load Comments