A triangle with three precisely placed satellites firing laser beams at each other sounds like something straight out of science fiction.but european space agency (ESA) plans to achieve this by 2035.
This project is known as Laser Interferometer Space Antenna (LISA)is like the famous LIGO experiment that discovered gravitational waves, only in space instead of in underground tunnels. This project, led by ESA, NASA and consortium of scientists. ESA recently gave the mission team: Official green light Construction of the spacecraft is scheduled to begin in January 2025 and launch 10 years later. Astrophysicists working on the mission, such as Max Planck Institute astrophysicist Sara Paczkowski, were elated by the news, calling the mission’s adoption “rewarding” and “very exciting.” .
“LISA will be sensitive to gravitational waves and ripples in the structure of space and time, which are currently not understood.” michael zevinan astrophysicist at the Adler Planetarium and part of the LIGO collaboration. gravitational waves Uncover the physics of black hole collisions, massive supernova explosions, and even the universe’s earliest moments. LISA’s new perspective is “similar to the first observations of the universe in light outside the visible range, such as X-rays and infrared light, which enabled an enormous amount of science, discovery, and understanding of the universe.” he added.
Since gravitational waves were first detected in 2016, astronomers have been eagerly exploring the universe through this new window. We hear the final moments of two black holes spiraling into each other, and learn how the highest energy events in the universe, such as supernovae and gamma-ray bursts, occur through the simultaneous discovery of light and gravitational waves from cosmic explosions. I learned about what happens.
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Common words between LISA and LIGO are: laser interferometer, describes the experimental setup. These projects allow him to observe how the distance between two objects changes slightly as gravitational waves ripple. They do this with two long arms. In LIGO’s case, it’s two large tunnels, each 4.5 miles long. These tunnels contain giant vacuum chamber tubes, with laser light traveling down each arm and reflecting off mirrors. If the light recombines at the center, it looks different if the passage of gravitational waves requires the laser to travel farther in one arm.
However, the types of gravitational waves that can be detected in experiments on Earth are limited. For gravitational waves, you need a long tunnel like LIGO to notice the ripples. The longer the arm, the longer waves can be detected. Underground detectors like LIGO are best at finding the shortest gravitational waves, the very high-frequency oscillations in spacetime that come from the last milliseconds before a black hole or neutron star collides. Part of the reason is that Earth is very active with activities that can confuse detectors. “Earthquakes, cars, ocean waves, and even clouds passing over the detector” create noise that prevents astronomers from hearing the low-frequency roar of the universe, it said. Simon BurkeLISA Charge Management Device Scientist at the University of Florida’s Institute for Precision Space Systems.
Ground-based detectors are limited in the scale of experiments. We cannot build buildings larger than Earth, or even larger than several states, and we are limited to the shortest gravitational waves. At the other end of the spectrum, pulsar timing arrays like NANOGrav measure vast distances between dead stars known as pulsars, so they can only hear the lowest frequencies emanating from giant supermassive black holes. . Everything in between requires LISA.
“So far, we have only heard sounds in a very narrow range of spacetime,” Zevin explains. “Ground-based detectors have been listening to the violins of a gravitational wave symphony. Pulsar timing arrays recently announced evidence that they are hearing bass sections from supermassive black holes throughout the universe. LISA is the first space-based gravitational wave instrument, listening to frequencies between two areas: the viola and cello sections of an orchestra.”
LISA consists of three spacecraft, each containing a solid cube of gold-platinum with a laser that spans the distance between the spacecraft and records changes caused by gravitational waves. This concept requires mind-boggling precision. To measure ripples as small as a billionth of a millimeter, the spacecraft must be so stable that only movement in space and time affects the test mass. The distance between the spacecraft will also be “greater than the diameter of the sun,” Burke said.
This technology allows astronomers to track collisions with celestial bodies. Binary star The project will map the gravity around the Milky Way’s most massive black hole, which lurks at the center of the galaxy, and test the theory of relativity in extreme environments that “may show deviations from Einstein’s predictions.” says Burke. Scientists also hope that LISA will help solve a long-standing question in astronomy: How do supermassive black holes grow to enormous sizes? Future experiments will finally allow us to observe so-called intermediate-mass black holes, which Zevin says are “the elusive mesons of the black hole family.” An important step on the road to becoming super-sized.
Sumeet KulkarniThe University of Mississippi gravitational wave astronomer also spoke about the significance of this moment for us here on Earth: A generation of physicists, astronomers, and engineers. ”
