Illustration of the LISA Pathfinder craft. Image via ESA/ATG medialab
The European Space Agency (ESA) is celebrating the news that its LISA Pathfinder mission to determine the feasibility of a space-based gravitational wave observatory has exceeded all expectations.
The launch of the LISA Pathfinder test craft has been one of astronomy’s first experiments into determining the real potential of what gravitational waves can offer since they were first confirmed by researchers in September 2015.
The announcement made by the ground-based Laser Interferometer Gravitational-Wave Observatory (LIGO) was a major milestone in astronomy, having proved a 100-year-old Albert Einstein theory that will now “let us look behind the curtain” of the universe.
With this discovery, LISA Pathfinder was blasted into space to take advantage of this new ability to observe distant cosmic objects like never before and see whether a space telescope could bring back even greater results than those achieved on Earth.
To put this potential into context, the detection made last year at LIGO was made at the 100Hz range, but if we are to truly see all there is to see in the universe, we need to be able to see gravitational waves at low frequencies between 0.1 mHz and 1Hz, which can only be achieved in space.
Five-times better than expected
Now, in a paper published to Physical Review Letters, the LISA Pathfinder team has confirmed that, not only has it proven to be a success, but it has achieved precise readings five-times better than anticipated.
Having reached its operational orbit 1.5m km from Earth, the craft began experimenting by internally releasing a pair of identical, 2kg, 46mm gold–platinum cubes.
The point of this being to monitor their relative positions as they move under the effect of gravity alone, and now the control achieved over these cubes has shown a gravitational wave space observatory is feasible.
The LISA Pathfinder mission. Image via ESA/ATG medialab; data: ESA/LISA Pathfinder Collaboration
Based on the researchers’ findings, LISA Pathfinder can monitor a frequency range between 60mHz and 1Hz, while greater improvements are expected to be made at even lower frequencies as low as 1mHz in the coming months.
“At the precision reached by LISA Pathfinder, a full-scale gravitational wave observatory in space would be able to detect fluctuations caused by the mergers of supermassive black holes in galaxies anywhere in the universe,” said Karsten Danzmann, director at the Max Planck Institute for Gravitational Physics.
