The Scientific Program Committee of the European Space Agency (ESA) formally approved the Laser Interferometer Space Antenna (LISA) mission. This step, formally called 'adoption,' authorizes the construction of the instruments and spacecraft, for which the Italian Space Agency will play a fundamental role. Led by ESA, with the participation of NASA and national space agencies, the mission has been made possible by an international consortium of scientists, the LISA Consortium, which also includes researchers at SISSA.
"The adoption of LISA by ESA is a pivotal moment for gravitational wave astrophysics. LISA will observe black holes millions of times heavier than the Sun up to cosmic dawn, when the first galaxies formed, helping us to understand the formation of structures in the primordial universe." explains Enrico Barausse, professor at SISSA and chair of the Fundamental Physics working group of the LISA consortium, which deals with exploring the implications of the mission for fundamental physics and gravity.
"LISA will also test the validity of Einstein's theory of General Relativity with unprecedented accuracy in highly dynamical regimes characterized by strong gravitational fields and velocities close to the speed of light, a research avenue that may revolutionize our understanding of fundamental physics and cosmology." he continues.
LISA will consist of a trio of satellites that will follow the Earth in its orbit around the Sun, forming an equilateral triangle in space, with each side being more than six times the distance between the Earth and the moon (2.5 million km). This configuration will allow for precise laser beam exchanges between the spacecraft, which will reveal minute variations in the distance between the satellites due to the passage of gravitational waves, uncovering waves of lower frequency, impossible to detect on earth.