The European Space Agency (ESA) has recently announced an ambitious project to create a space antenna of a laser interferometer, known as the Laser Interferometer Space Antenna (LISA). This project, set to begin next year, aims to construct three spacecraft in order to detect gravitational waves in space.
While LISA will follow the same basic principles as the laser interferometric gravity-wave observatory (LIGO) located on the ground, it will be positioned in space. Furthermore, it will consist of three interconnected space stations positioned 2.5 million kilometers apart from each other.
Gravitational wave detectors typically use lasers reflected from multiple mirrors. Any changes in the position of these mirrors, including the impact of gravitational waves on them, alter the interference pattern. Ground detectors, however, are limited by the distance between the mirrors and can only detect high-frequency gravitational waves that occur in the final moments before the fusion of astronomical objects.
LISA, on the other hand, will be able to track even low-frequency gravitational waves, necessitating the large distance between the mirrors of the interferometer and their significant removal from the seismic noise of the Earth. The LISA design includes a protective spacecraft shell, a laser spanning up to 2.5 million kilometers, and a telescope for focusing the laser light.
ESA has already conducted a preliminary mission to test the technology, and the results have exceeded expectations by 20 times. This validates the high potential of the technology for real scenarios, paving the way for the swift deployment of the LISA system in space.
Once launched, scientists will be able to predict the collisions of black holes, study the physics of their interactions, and provide information for observations through optical telescopes. Of particular interest is the possibility of observing the mergers of ultra-massive black holes, as well as gravitational waves that emerged immediately after significant explosions. These observations can open new horizons in our understanding of the early history of the Universe.
Despite the excitement surrounding the project, the launch of LISA is currently scheduled for 2034. Nevertheless, it promises to be a significant milestone in the field of astrophysics and space research.