The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a large-scale physics experiment and observatory designed to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. Two large observatories were built in the United States with the aim of detecting gravitational waves by laser interferometry. These observatories use mirrors spaced four kilometers apart to measure changes in length—over an effective span of 1120 km—of less than one ten-thousandth the charge diameter of a proton.
Yellow Dog Linux (YDL) is a discontinued free and open-source operating system for high-performance computing on multi-core processor computer architectures, focusing on GPU systems and computers using the POWER7 processor. The original developer was Terra Soft Solutions, which was acquired by Fixstars in October 2008. Yellow Dog Linux was first released in the spring of 1999 for Apple Macintosh PowerPC-based computers. The last version, Yellow Dog Linux 7, was released on August 6, 2012. Yellow Dog Linux lent its name to the popular YUM Linux software updater, derived from YDL's YUP and thus called Yellowdog Updater, Modified.
Rainer "Rai" Weiss is a German-born American physicist, known for his contributions in gravitational physics and astrophysics. He is a professor of physics emeritus at MIT and an adjunct professor at LSU. He is best known for inventing the laser interferometric technique which is the basic operation of LIGO. He was Chair of the COBE Science Working Group.
Cell is a 64-bit multi-core microprocessor microarchitecture that combines a general-purpose PowerPC core of modest performance with streamlined coprocessing elements which greatly accelerate multimedia and vector processing applications, as well as many other forms of dedicated computation.
GEO600 is a gravitational wave detector located near Sarstedt, a town 20 kilometres (12 mi) to the south of Hanover, Germany. It is designed and operated by scientists from the Max Planck Institute for Gravitational Physics, Max Planck Institute of Quantum Optics and the Leibniz Universität Hannover, along with University of Glasgow, University of Birmingham and Cardiff University in the United Kingdom, and is funded by the Max Planck Society and the Science and Technology Facilities Council (STFC).
Ronald William Prest Drever was a Scottish experimental physicist. He was a professor emeritus at the California Institute of Technology, co-founded the LIGO project, and was a co-inventor of the Pound–Drever–Hall technique for laser stabilisation, as well as the Hughes–Drever experiment. This work was instrumental in the first detection of gravitational waves in September 2015.
Gravitational waves are transient displacements in a gravitational field – generated by the motion or acceleration of gravitating masses – that radiate outward from their source at the speed of light. They were first proposed by Oliver Heaviside in 1893 and then later by Henri Poincaré in 1905 as the gravitational equivalent of electromagnetic waves. In 1916, Albert Einstein demonstrated that gravitational waves result from his general theory of relativity as ripples in spacetime.
A gravitational-wave detector is any device designed to measure tiny distortions of spacetime called gravitational waves. Since the 1960s, various kinds of gravitational-wave detectors have been built and constantly improved. The present-day generation of laser interferometers has reached the necessary sensitivity to detect gravitational waves from astronomical sources, thus forming the primary tool of gravitational-wave astronomy.
Gravitational-wave astronomy is a subfield of astronomy concerned with the detection and study of gravitational waves emitted by astrophysical sources.
The LIGO Scientific Collaboration (LSC) is a scientific collaboration of international physics institutes and research groups dedicated to the search for gravitational waves.
Fixstars Solutions, Inc. is a software and services company specializing in multi-core processors, particularly in Nvidia's GPU and CUDA environment, IBM Power7, and Cell. They also specialize in solid-state drives and currently manufacture the world's largest SATA drives.
David Howard Reitze is an American laser physicist who is professor of physics at the University of Florida and served as the scientific spokesman of the Laser Interferometer Gravitational-Wave Observatory (LIGO) experiment in 2007-2011. In August 2011, he took a leave of absence from the University of Florida to be the Executive Director of LIGO, stationed at the California Institute of Technology, Pasadena, California. He obtained his BA in 1983 from Northwestern University, his PhD in physics from the University of Texas at Austin in 1990, and had positions at Bell Communications Research and Lawrence Livermore National Laboratory, before taking his faculty position at the University of Florida. He is a Fellow of the American Physical Society, the Optical Society, and the American Association for the Advancement of Science.
INDIGO or IndIGO is a consortium of Indian gravitational wave physicists. It is an initiative to set up advanced experimental facilities for a multi-institutional observatory project in gravitational-wave astronomy to be located near Aundha Nagnath, Hingoli District, Maharashtra, India. Predicted date of commission is in 2030.
The first direct observation of gravitational waves was made on 14 September 2015 and was announced by the LIGO and Virgo collaborations on 11 February 2016. Previously, gravitational waves had been inferred only indirectly, via their effect on the timing of pulsars in binary star systems. The waveform, detected by both LIGO observatories, matched the predictions of general relativity for a gravitational wave emanating from the inward spiral and merger of a pair of black holes of around 36 and 29 solar masses and the subsequent "ringdown" of the single resulting black hole. The signal was named GW150914. It was also the first observation of a binary black hole merger, demonstrating both the existence of binary stellar-mass black hole systems and the fact that such mergers could occur within the current age of the universe.
GW170817 was a gravitational wave (GW) signal observed by the LIGO and Virgo detectors on 17 August 2017, originating from the shell elliptical galaxy NGC 4993, about 140 million light years away. The signal was produced by the last moments of the inspiral process of a binary pair of neutron stars, ending with their merger. It was the first GW observation to be confirmed by non-gravitational means. Unlike the five previous GW detections—which were of merging black holes and thus not expected to produce a detectable electromagnetic signal—the aftermath of this merger was seen across the electromagnetic spectrum by 70 observatories on 7 continents and in space, marking a significant breakthrough for multi-messenger astronomy. The discovery and subsequent observations of GW170817 were given the Breakthrough of the Year award for 2017 by the journal Science.
LIGO is a 2019 American documentary film that tells the inside account of the discovery by the international LIGO Scientific Collaboration of the first observation of gravitational waves in September 2015, a discovery that led two years later to the Nobel Prize in Physics for LIGO physicists Rai Weiss, Kip Thorne and Barry Barish. In December 2019, National Geographic named the LIGO detections at the top of its list of "The 20 Top Scientific Discoveries of the Decade".
GW 190814 was a gravitational wave (GW) signal observed by the LIGO and Virgo detectors on 14 August 2019 at 21:10:39 UTC, and having a signal-to-noise ratio of 25 in the three-detector network. The signal was associated with the astronomical super event S190814bv, located 790 million light years away, in location area 18.5 deg2 towards Cetus or Sculptor. No optical counterpart was discovered despite an extensive search of the probability region.
Rana X. Adhikari is an American experimental physicist. He is a professor of physics at the California Institute of Technology (Caltech) and an associate faculty member of the International Centre for Theoretical Sciences of Tata Institute of Fundamental Research (ICTS-TIFR).
The Space Analog for the Moon & Mars (SAM) is a hermetically sealed and pressurized terrestrial analog site. This hi-fidelity research vessel is located at the University of Arizona Biosphere 2 research campus at the base of Santa Catalina Mountains near Oracle, Arizona, USA. Following two and a half years in construction led by Director of Research and principal designer Kai Staats, in April 2023 SAM joined the list of over a dozen active analog stations that enable human analog missions, field tests to “validate architecture concepts, demonstrate technologies” and “test robotics, vehicles, habitats, communication systems, in situ resource utilization (ISRU) and human performance as it relates to human space exploration”. Supported by an international team of specialists with the University of Arizona, NASA, the National Geographic Society, and commercial partners, the core foci of SAM are scientific research objectives related to human space exploration, long-duration other-world habitation, and sustainability of Earth systems and human quality of life. In 2025, SAM will participate in The World's Biggest Analog (WBA), “an international collaboration of researchers, scientists, educators and entrepreneurs working to unite the world’s analogs through a unique and historical mission”.
