The European Space Agency (ESA) spacecraft designed to hunt for gravitational waves is well on track for its November 27 launch. With this mission, the technology needed to detect gravitational waves will be tested in space for the first time, and it could revolutionize the study of astronomy.
If you don’t know, gravitational waves are tiny distortions in spacetime caused by cosmic catastrophes, such as merging black holes, collapsing stars, and supernovae. Gravitational waves theoretically transport energy via gravitational radiation. Notably, in this instance, “theoretically” is a rather important word, as we haven’t actually seen these waves yet.
That said, thanks to indirect observations of their effects, scientists know that gravitational waves exist; however, direct observations of gravitational waves have remained somewhat elusive; however, that may all change soon, and it’s all thanks to LISA.
The LISA Pathfinder mission (Laser Interferometer Space Antenna) will pave the way for future space-based projects that hope to observe gravitational waves. In so doing, it heralds a new era of gravitational wave astronomy and allows us a new glimpse of some of the most energetic events in the universe.
“The spacecraft has finished its test campaign at IABG. All tests were successful and LISA Pathfinder has been certified to start the launch campaign,” César García Marirrodriga, LISA Pathfinder Project Manager, told FQTQ. “The current plan is launching on November 27, in the early hours,” Marirrodriga added, noting that all is going as planned.
The probe arrived at IABG in March this year. Now, its two modules have been tested, most of the time this was done separately, which allowed engineers to run individual activities in parallel, increasing the efficiency and improving the schedule. In addition, a fit-check has been performed with the launch vehicle adapter, which is used to attach the spacecraft on the Vega booster. Next, the mission’s science experiment, known as the LISA Technology Package (LTP) has been integrated into the science module. Then, science and propulsion modules have been joined, forming the “Launch Composite” – the configuration in which they will be launched.
The final series of activities at IABG included an acoustic test, carried out to make sure the modules can survive the intense noise generated by the rocket engines after the ignition. The last, but not least, important step was the “mass property measurement” of the “Launch Composite.” During this measurement, the spacecraft was precisely weighed to determine its mass, the center of gravity, and the moments of inertia, which will be used to calculate the flight trajectory.
“We are very happy with the test results, and very excited about the launch campaign, operations, and scientific results,” Marirrodriga said.
LISA Pathfinder will test novel technologies in space whose function and performance cannot be tested on the ground at all or only in a limited way. It will use two test masses only 15 inches (38 cm) apart and placed on a single spacecraft. The test masses will be in a near-perfect gravitational free-fall and the scientists will control and measure their motion with an unprecedented accuracy.
After the launch, the spacecraft will be delivered to the Lagrangian point L1, located some 1.5 million kilometers from Earth in the direction of the Sun. The operational phase will last six months but could be extended up to one year.
“LISA Pathfinder is an essential step towards the observation and understanding of the universe through low-frequency gravitational waves,” Marirrodriga said. It may allow us to better understand the solar system in our local area and beyond.
In the end, the mission will pave the way for the ESA’s Evolved Laser Interferometer Space Antenna (eLISA), a gravitational wave observatory planned to be launched in 2034.