The Monitor of All-sky X-ray Image (MAXI) is an X-ray telescope mounted on the International Space Station since 2009. The instrument uses wide field of view X-ray detectors to perform a sky survey, measuring the brightness of X-ray sources every 96 minutes (one ISS orbit).
MAXI was developed by the Japan Aerospace Exploration Agency (JAXA). It was launched in 2009 and mounted on the outside of the Kibō module.
The instrument uses several wide field of view X-ray detectors, including the Gas Slit Camera (GSC) and the Solid-state Slit Camera (SSC), [1] to monitor astronomical X-ray sources for variability. MAXI conducts a full sky survey every 96 minutes (one ISS orbit).
In August 2022 a fast X-ray follow-up observation program was started with the NICER instrument named "OHMAN (On-orbit Hookup of MAXI and NICER)" to detect sudden bursts in X-ray phenomena. [2]
MAXI operations commenced in August 2009 with an original two-year operation plan. JAXA has extended mission duration multiple times with the latest extension to March 2021. [3]
MAXI helped discover the rapidly rotating black-hole/star system MAXI J1659-152. [4]
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iSEEP Wide-Field MAXI (iWF-MAXI) is a follow-on instrument to the current MAXI. Compared with MAXI, which can only monitor 2% of the celestial sphere instantaneously, iWF-MAXI is always capable of monitoring 10%, and can monitor up to 80% in 92 minutes. iWF-MAXI will utilize the i-SEEP (IVA-replaceable Small Exposed Experiment Platform) bus, an exposure adapter for middle-sized payloads in JEM-EF. Chosen as an ISAS Mission of Opportunity in 2015, [5] iWF-MAXI has started observation at the ISS in 2019. [6]
Kibō, also known as the Japanese Experiment Module (JEM), is a Japanese science module for the International Space Station (ISS) developed by JAXA. It is the largest single ISS module, and is attached to the Harmony module. The first two pieces of the module were launched on Space Shuttle missions STS-123 and STS-124. The third and final components were launched on STS-127.
The Rossi X-ray Timing Explorer (RXTE) was a NASA satellite that observed the time variation of astronomical X-ray sources, named after physicist Bruno Rossi. The RXTE had three instruments — an All-Sky Monitor, the High-Energy X-ray Timing Experiment (HEXTE) and the Proportional Counter Array. The RXTE observed X-rays from black holes, neutron stars, X-ray pulsars and X-ray bursts. It was funded as part of the Explorer program and was also called Explorer 69.
The National Space Development Agency of Japan, or NASDA, was a Japanese national space agency established on October 1, 1969 under the National Space Development Agency Law only for peaceful purposes. Based on the Space Development Program enacted by the Minister of Education, Culture, Sports, Science and Technology (MEXT), NASDA was responsible for developing satellites and launch vehicles as well as launching and tracking them.
The Japan Aerospace Exploration Agency (JAXA) is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into orbit, and is involved in many more advanced missions such as asteroid exploration and possible human exploration of the Moon. Its motto is One JAXA and its corporate slogan is Explore to Realize.
Yohkoh, known before launch as Solar-A, was a Solar observatory spacecraft of the Institute of Space and Astronautical Science (Japan), in collaboration with space agencies in the United States and the United Kingdom. It was launched into Earth orbit on August 30, 1991 by the M-3SII rocket from Kagoshima Space Center. It took its first soft X-ray image on 13 September 1991, 21:53:40, and movie representations of the X-ray corona over 1991-2001 are available at the Yohkoh Legacy site.
The INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) is a space telescope for observing gamma rays of energies up to 8 MeV. It was launched by the European Space Agency (ESA) into Earth orbit in 2002, and is designed to provide imaging and spectroscopy of cosmic sources. In the MeV energy range, it is the most sensitive gamma ray observatory in space. It is sensitive to higher energy photons than X-ray instruments such as NuSTAR, the Neil Gehrels Swift Observatory, XMM-Newton, and lower than other gamma-ray instruments such Fermi and HESS.
Suzaku was an X-ray astronomy satellite developed jointly by the Institute of Space and Aeronautical Science at JAXA and NASA's Goddard Space Flight Center to probe high-energy X-ray sources, such as supernova explosions, black holes and galactic clusters. It was launched on 10 July 2005 aboard the M-V launch vehicle on the M-V-6 mission. After its successful launch, the satellite was renamed Suzaku after the mythical Vermilion bird of the South.
The General Coordinates Network (GCN), formerly known as the Gamma-ray burst Coordinates Network, is an open-source platform created by NASA to receive and transmit alerts about astronomical transient phenomena. This includes neutrino detections by observatories such as IceCube or Super-Kamiokande, gravitational wave events from the LIGO, Virgo and KAGRA interferometers, and gamma-ray bursts observed by Fermi, Swift or INTEGRAL. One of the main goals is to allow for follow-up observations of an event by other observatories, in hope to observe multi-messenger events.
Hinode, formerly Solar-B, is a Japan Aerospace Exploration Agency Solar mission with United States and United Kingdom collaboration. It is the follow-up to the Yohkoh (Solar-A) mission and it was launched on the final flight of the M-V rocket from Uchinoura Space Center, Japan on 22 September 2006 at 21:36 UTC. Initial orbit was perigee height 280 km, apogee height 686 km, inclination 98.3 degrees. Then the satellite maneuvered to the quasi-circular Sun-synchronous orbit over the day/night terminator, which allows near-continuous observation of the Sun. On 28 October 2006, the probe's instruments captured their first images.
The International Astrophysical Observatory "GRANAT", was a Soviet space observatory developed in collaboration with France, Denmark and Bulgaria. It was launched on 1 December 1989 aboard a Proton rocket and placed in a highly eccentric four-day orbit, of which three were devoted to observations. It operated for almost nine years.
The Small Astronomy Satellite 3 was a NASA X-ray astronomy space telescope. It functioned from 7 May 1975 to 9 April 1979. It covered the X-ray range with four experiments on board. The satellite, built by the Johns Hopkins University Applied Physics Laboratory (APL), was proposed and operated by MIT's Center for Space Research (CSR). It was launched on a Scout vehicle from the Italian San Marco platform near Malindi, Kenya, into a low-Earth, nearly equatorial orbit. It was also known as Explorer 53, as part of NASA's Explorer program.
Hitomi, also known as ASTRO-H and New X-ray Telescope (NeXT), was an X-ray astronomy satellite commissioned by the Japan Aerospace Exploration Agency (JAXA) for studying extremely energetic processes in the Universe. The space observatory was designed to extend the research conducted by the Advanced Satellite for Cosmology and Astrophysics (ASCA) by investigating the hard X-ray band above 10 keV. The satellite was originally called New X-ray Telescope; at the time of launch it was called ASTRO-H. After it was placed in orbit and its solar panels deployed, it was renamed Hitomi. The spacecraft was launched on 17 February 2016 and contact was lost on 26 March 2016, due to multiple incidents with the attitude control system leading to an uncontrolled spin rate and breakup of structurally weak elements.
OSO 7 or Orbiting Solar Observatory 7, before launch known as OSO H is the seventh in the series of American Orbiting Solar Observatory satellites launched by NASA between 1962 and 1975. OSO 7 was launched from Cape Kennedy on 29 September 1971 by a Delta N rocket into a 33.1° inclination, low-Earth orbit, and re-entered the Earth's atmosphere on 9 July 1974. It was built by the Ball Brothers Research Corporation (BBRC), now known as Ball Aerospace, in Boulder Colorado.
MAXI J1659-152 is a rapidly rotating black hole/star system, discovered by NASA's Swift space telescope on September 25, 2010. On March 19, 2013, ESA's XMM-Newton space telescope helped to identify a star and a black hole that orbit each other at the rate of once every 2.4 hours.
The Neutron Star Interior Composition ExploreR (NICER) is a NASA telescope on the International Space Station, designed and dedicated to the study of the extraordinary gravitational, electromagnetic, and nuclear physics environments embodied by neutron stars, exploring the exotic states of matter where density and pressure are higher than in atomic nuclei. As part of NASA's Explorer program, NICER enabled rotation-resolved spectroscopy of the thermal and non-thermal emissions of neutron stars in the soft X-ray band with unprecedented sensitivity, probing interior structure, the origins of dynamic phenomena, and the mechanisms that underlie the most powerful cosmic particle accelerators known. NICER achieved these goals by deploying, following the launch, and activation of X-ray timing and spectroscopy instruments. NICER was selected by NASA to proceed to formulation phase in April 2013.
The Nanoracks CubeSat Deployer (NRCSD) is a device to deploy CubeSats into orbit from the International Space Station (ISS).
ULTRASAT is a space telescope in a smallsat format that will detect and monitor transient astronomical events in the near-ultraviolet (220–280 nm) spectral region. ULTRASAT will observe a large patch of sky with a 210 square degrees field of view, alternating every six months between the southern and northern hemisphere. The satellite is planned to be launched into a geosynchronous orbit in early 2026. All ULTRASAT data will be transmitted to the ground in real time. Upon detection of a transient event, ULTRASAT will provide alerts within 20 minutes to other ground-based and space telescopes to be directed to the source for further observation of the event in other wavelength bands.
The X-Ray Imaging and Spectroscopy Mission, formerly the X-ray Astronomy Recovery Mission (XARM), is an X-ray space telescope mission of the Japan Aerospace Exploration Agency (JAXA) in partnership with NASA to provide breakthroughs in the study of structure formation of the universe, outflows from galaxy nuclei, and dark matter. As the only international X-ray observatory project of its period, XRISM will function as a next generation space telescope in the X-ray astronomy field, similar to how the James Webb Space Telescope, Fermi Space Telescope, and the Atacama Large Millimeter Array (ALMA) Observatory are placed in their respective fields.
Martian Moons eXploration (MMX) is a robotic space probe set for launch in 2026 to bring back the first samples from Mars' largest moon Phobos. Developed by the Japan Aerospace Exploration Agency (JAXA) and announced on 9 June 2015, MMX will land and collect samples from Phobos once or twice, along with conducting Deimos flyby observations and monitoring Mars's climate.
Lobster-eye optics are a biomimetic design, based on the structure of the eyes of a lobster with an ultra wide field of view, used in X-ray optics. This configuration allows X-ray light to enter from multiple angles, capturing more X-rays from a larger area than other X-ray telescopes. The idea was originally proposed for use in X-ray astronomy by Roger Angel in 1979, with a similar idea presented earlier by W. K. H. Schmidt in 1975. It was first used by NASA on a sub-orbital sounding rocket experiment in 2012. The Lobster Eye Imager for Astronomy, a Chinese technology demonstrator satellite, was launched in 2022. The Chinese Einstein Probe, launched in 2024, is the first major space telescope to use lobster-eye optics. Several other such space telescopes are currently under development or consideration.