The LISA Consortium is a large international collaboration that combines the resources and expertise from scientists in many countries all over the world. Together with ESA and NASA, the LISA Consortium is working to bring the LISA Mission to […]
The gravitational waves that LISA is designed to observe have typical timescales of hours. So long as the distance between the satellites is smoothly changing over these time scales, the gravitational waves can be observed as an additional modulation on top of this smooth change. Each satellite is in an independent Keplerian orbit around the Sun with the plane of the triangle inclined at 60 degrees to the plane of the ecliptic. Over the course of the mission, the nominal 2.5 million kilometer distance between each satellite will vary by hundreds of thousands of kilometers. LISA will be able to […]
No. Both ground motion and time variations in familiar Newtonian gravity from spurious mass motions on the Earth prevent observations below about 1 Hz on the ground. It is necessary to make measurements in space in order to observe many of the important astrophysical sources throughout the […]
Gravitational waves are ripples in the fabric of space-time generated by some of the most powerful astrophysical events – such as collisions of black holes and exploding stars. Gravitational waves travel at the speed of light through the universe. They allow us to explore the dark side of the […]
If you are a professional researcher, you may want to join the LISA Consortium. In the US, you should check out NASA’s Gravitational Wave Science Interest Group (GWSIG) https://pcos.gsfc.nasa.gov/sigs/gwsig.php. If you are a student, you may consider applying for an internship at a NASA center involved with LISA […]
LISA is led by the European Space Agency (ESA), which in 2017 selected LISA for study as a large-class mission in the Cosmic Visions Programme. LISA was Adopted as a project by ESA’s Science Program Council in January 2024. Partnering with ESA are NASA and a collection of European National space agencies. NASA will provide three critical hardware elements for LISA: lasers, telescopes, and charge management devices. In addition, NASA is developing a science ground segment to process the LISA telemetry and produce scientific data products for public consumption. NASA scientists, engineers, and managers are working closely with the ESA […]
The LISA mission is designed for 4 years of nominal science operations, with a potential extended mission of up to 6 years. In addition to wear-and-tear of the spacecraft and its instruments, limitations to LISA’s lifetime come from the amount of propellant available to perform the drag-free flight of the spacecraft around the test masses, the long-term stability of the orbits that form the constellation, and communications difficulties associated with increasing distance between the consteallation and […]
LISA’s data and telemetry requirements are relatively modest when compared to many other astrophysics missions. While the precise details are being developed as part of the mission formulaiton process, the rough numbers are known. During normal operations, only one of the three LISA spacecraft will be in contact with the ground. In addition to transmitting its own data, the spacecraft will serve as a relay for data from the other two spacecraft, which will share data over a dedicated inter-constellation link. This is efficient because the separation between spacecraft (2.5Mkm) is roughly 20x smaller than the distance to Earth (approximately […]
Interferometry is a technique that uses the interference of waves to make precise measurements. The wavelength of the interfering waves acts like the tick marks on a ruler for measuring distance. Optical interferometers can make very precise measurements because the wavelength of the light waves they use is small — around one micron for instruments like LIGO and LISA. A fundamental limitation of interferometry is that precision of the measurement is limited by the stability of the waves used in the interferometer. For an optical interferometer, if the wavelength of the light fluctuates, a spurious signal will be generated that […]
The orbits of the LISA spacecraft are set up in such a way that the constellation maintains a nearly perfect equilateral triangular shape that is inclined by roughly 60 deg with respect to the ecliptic plane. Once each spacecraft is inserted into its predetermined orbit, tracking from the ground will be used to precisely locate them and determine their relative positions. The spacecraft will then undergo a “constellation acquisition” procedure which begins with one spacecraft turning on its laser while its partner spacecraft scans the sky. At some point during the scan, an acquisition sensor on the partner spacecraft will […]