Czech scientists develop technology for giant space gravitational wave detector
Experts from the Czech Academy of Sciences have presented their first contribution to the LISA space mission. Approved by the European Space Agency (ESA) a few days ago, the Czech component will be crucial to the functioning of the giant satellite system, which aims to measure gravitational waves.
LISA, standing for Laser Interferometer Space Antenna, is a space-based gravitational wave detector that uses precision lasers to do its job. Or at least, it will once it is finished – the mission is scheduled to launch in the mid-2030s.
Consisting of three spacecraft separated by millions of miles and arranged in a triangle, LISA will trail behind the Earth as it orbits the sun. These three spacecraft will relay laser beams back and forth between each other, and the combined signals will search for gravitational wave signatures that come from distortions of spacetime.
The technology developed by Czech scientists will be in charge of switching between the main and backup laser and will be critical to the functioning of the entire system, says Asen Christov from the Institute of Physics.
“It is key; it will be at the beginning of the whole optical system. If it failed, the laser would not go any further.”
The three satellites will form an equilateral triangle in space where the sides of the triangle, also called LISA's "arms", extend huge distances, far bigger than our own planet Earth. Although there are several gravitational wave detectors on Earth, they cannot capture all types of waves. A space-based configuration allows for a much larger detector, which allows scientists to study regions of the gravitational wave spectrum that are inaccessible from Earth, explains Jiří Svoboda from the Institute of Astronomy.
"LISA’s arms will be two and a half million kilometres long. On Earth, some waves escape unnoticed, so we are going into space, where we are not limited by length."
Measuring gravitational waves has the potential to help scientists learn more about parts of the universe that are otherwise invisible, such as black holes. That is another reason why LISA’s arms need to be so long – a giant detector the size of the Sun is needed to catch gravitational waves from orbiting black holes millions of times more massive than our Sun. Studying gravitational waves, the scientists hope, will complement our knowledge about the beginnings, evolution and structure of our universe.
LISA is a collaborative mission led by the European Space Agency (ESA) in cooperation with NASA and an international consortium of scientists. Scientists from four institutes at the Czech Academy of Sciences are part of this international consortium: the institutes of astronomy, physics, atmospheric physics and thermomechanics.
Technical manager Libor Švéda says that the ESA was surprised at the possibilities presented by the technology.
"We had a conference with people from the European Space Agency, and they were surprised that we could measure something which they thought could only be calculated."
When the testing is finished, the instruments for the real satellites will be manufactured by Czech companies. It will, however, take quite some time before the satellites see lift-off – it could take as long as eleven years to test all the components.
