Albert Einstein predicted the existence of gravitational waves as a consequence of his theory of general relativity, published in 1915.

Gravitational waves are disturbances in the curvature of spacetime, caused by the acceleration of massive objects.

Gravitational waves travel at the speed of light, which is approximately 299,792,458 meters per second.

The first direct detection of gravitational waves was made on September 14, 2015, by the Laser Interferometer Gravitational-Wave Observatory (LIGO).

The gravitational waves detected in 2015 were produced by the collision of two black holes, located approximately 1.3 billion light-years away.

LIGO is a network of detectors located in the United States, designed to detect gravitational waves.

The Virgo detector is a gravitational wave detector located in Cascina, Italy, and is part of the global network of gravitational wave detectors.

The detection of gravitational waves has far-reaching implications, including confirming a key prediction of Einstein's theory of general relativity, allowing us to study the properties of black holes and neutron stars, and providing a new tool for exploring the universe.

Detecting gravitational waves is challenging due to their extremely small amplitude, the need for highly sensitive detectors, and the difficulty in distinguishing gravitational waves from other signals.

Gravitational wave astronomy has the potential to revolutionize our understanding of the universe, allowing us to study the properties of black holes and neutron stars, explore the early universe, and detect supernovae and other violent cosmic events.

LISA is a proposed space-based gravitational wave detector, designed to detect gravitational waves from a wider range of sources and with greater sensitivity than ground-based detectors.

The expected launch date of LISA is 2034.

LISA's scientific goals include studying the properties of black holes and neutron stars, exploring the early universe, and detecting supernovae and other violent cosmic events.

LISA is expected to be 1000 times more sensitive than ground-based detectors.

LISA is expected to revolutionize our understanding of gravity, provide new insights into the formation and evolution of black holes and neutron stars, and allow us to study the early universe in unprecedented detail.