What does it take to prove these incredibly elusive gravitational waves in space? The key technology behind it – Laser Interferometry – and other LISA-specific features will be touched upon on this category page!
Proven technology
Important equipment and technologies that will be used in LISA mission are already space-tested! In more detail: The Heritage of LISA Pathfinder.
PRECISION
LISA´s optical benches work with an incredible precision. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua
Ask LISA
The new page “Questions about LISA” provides answers to FAQ’s about technical details, mission design etc. Get the TOP4 in TECH.
The technology of LISA
The LISA instrument will consist of three spacecraft in a triangular configuration with 2.5 million kilometers (1.5 million mile) arms, moving in an Earth-like orbit around the Sun. Gravitational waves from sources throughout the Universe will produce slight oscillations in the arm lengths (smaller than the diameter of an atom). LISA will capture these motions and thus measure the gravitational waves by using laser links to monitor the displacements of test masses free-falling inside the spacecraft. The LISA satellites are being built by ESA, ESA member nations, and NASA.
LISA Technology: The revolutionary concept of sciencecraft
The classical distinction between spacecraft and payload doesn’t fit LISA well, because the LISA spacecraft are not just providing the infrastructure for the instruments. Each LISA spacecraft is part of the instrument itself because it protects the free-falling test masses from disturbances. The LISA spacecraft must thus be designed and built with the gravitational requirements of the free-falling test masses in mind.
You are familiar with the answers here … but not all of them? Go ahead for the rest.
You are familiar with the answers here … but not all of them?
Then go ahead and look at the rest of the list .
You are familiar with the answers here … but not all of them? Then go ahead and look at the rest of the list .
Questions about LISA
Burning questions about the technical aspects of the mission? From a more comprehensive list, here are the top 4 FAQ entries:
Questions about LISA
General questions about the theory and science behind this project? From a more comprehensive list, here are the top 3 FAQ entries:
Burning questions about the technical aspects of the mission? From a more comprehensive list, here are the top 4 FAQ entries:
Questions about LISA
General questions about the theory and science behind this project? From a more comprehensive list, here are the top 3 FAQ entries:
Burning questions about the technical aspects of the mission? From a more comprehensive list, here are the top 4 FAQ entries:
Gravitational waves are ripples in the fabric of space-time generated by some of the most powerful astrophysical events – such as exploding stars and collisions of two black holes at the centres of galaxies. Gravitational waves travel at the speed of light through the universe, unhindered by intervening mass – to gravitational waves the universe is transparent. That is why gravitational waves are the cosmic messengers that allow us to explore the so far dark side of the universe.
LISA’s distance measuring system is a continuous interferometric laser ranging scheme, similar to systems used for radar-tracking of spacecraft. But for LISA, the direct reflection of laser light, such as in a normal Michelson interferometer, is not feasible due to the large distance of million km between the spacecraft: Diffraction expands the laser beam so much that for each Watt of laserpower sent, only about 250 pW are received. Direct reflection would thus result in an attenuation factor of about 6.25 x 10-20, yielding about one photon in every three days.
Questions about LISA
General questions about the theory and science behind this project? From a more comprehensive list, here are the top 3 FAQ entries:
Burning questions about the technical aspects of the mission? From a more comprehensive list, here are the top 4 FAQ entries:
Gravitational waves are ripples in the fabric of space-time generated by some of the most powerful astrophysical events – such as exploding stars and collisions of two black holes at the centres of galaxies. Gravitational waves travel at the speed of light through the universe, unhindered by intervening mass – to gravitational waves the universe is transparent. That is why gravitational waves are the cosmic messengers that allow us to explore the so far dark side of the universe.
The Gravitational Universe will open a new window in astronomy using powerful sources of gravitational waves to probe a universe that cannot be probed by other means. Significant advances were made, by using our first sense for observing the universe, electromagnetic radiation. But most of the universe remains electromagnetically dark because on astronomical scales gravitation is the real engine of the universe. LISA will provide us with a new sense for observing the so far dark universe. It will let us listen to gravity and thus let us go further than any alternative.
LISA´s payload consists of two identical units on each spacecraft. Each unit contains a Gravitational Reference Sensor (GRS) with an embedded free-falling test mass that acts both as end point of the optical length measurement and as geodesic reference test particle. A telescope transmits the laser light along the arm and also receives the weak light (few hundred pico-Watts!) from the other end. Laser interferometry is performed on an optical bench in between the telescope and the GRS.
Questions about LISA
General questions about the theory and science behind this project? From a more comprehensive list, here are the top 3 FAQ entries:
Burning questions about the technical aspects of the mission? From a more comprehensive list, here are the top 4 FAQ entries:
Gravitational waves are ripples in the fabric of space-time generated by some of the most powerful astrophysical events – such as exploding stars and collisions of two black holes at the centres of galaxies. Gravitational waves travel at the speed of light through the universe, unhindered by intervening mass – to gravitational waves the universe is transparent. That is why gravitational waves are the cosmic messengers that allow us to explore the so far dark side of the universe.
The Gravitational Universe will open a new window in astronomy using powerful sources of gravitational waves to probe a universe that cannot be probed by other means. Significant advances were made, by using our first sense for observing the universe, electromagnetic radiation. But most of the universe remains electromagnetically dark because on astronomical scales gravitation is the real engine of the universe. LISA will provide us with a new sense for observing the so far dark universe. It will let us listen to gravity and thus let us go further than any alternative.
The usual structural and thermal analysis of the spacecraft has therefore been extended to include gravitational effects as well to ensure that the requirements on gravity gradient at the position of the test masses is fully met. In addition, the payload controls the position of the spacecraft during science operations, rendering the spacecraft effectively a part of the instrument. The importance of the co-design and the co-operation of spacecraft and payload is captured in the term “sciencecraft”.
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