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Einstein Probe
The Einstein Probe (EP) is an X-ray space telescope mission by Chinese Academy of Sciences (CAS) in partnership with European Space Agency (ESA) and the Max Planck Institute for Extraterrestrial Physics (MPE) dedicated to time-domain high-energy astrophysics. The primary goals are "to discover high-energy transients and monitor variable objects". The telescope was launched by a Long March 2C rocket from the Xichang Satellite Launch Centre in China, on 9 January 2024, at 07:03 UTC. Scientific objectives The primary science objectives are: # Identify inactive black holes to study how matter is precipitated there by detecting the transient events that take the form of X-ray flares; # Detect the electromagnetic counterpart of events triggering gravitational waves such as the merger of neutron stars which will be discovered by the next generation of gravitational wave detectors; # Carry out permanent monitoring of the entire sky to detect the various transient phenomena and carry o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobster-eye Optics
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. Description While most animals have refractive eyes, lobsters and other crustaceans have reflective eyes. The eyes of a crustacean contain clusters of cells, each reflecting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobster Eye Imager For Astronomy
Lobster Eye Imager for Astronomy (LEIA) (also known as EP-WXT-pathfinder) is a wide-field X-ray imaging space telescope built by Chinese Academy of Sciences (CAS). It was launched on July 27, 2022 onboard of SATech-01 satellite. It is designed for a lifetime of two years. Project conception and design LEIA has a sensor module giving it a field of view of 340 square degrees. It is a preliminary mission testing the sensor design for the Einstein Probe which has a 12 sensor module Wide-field X-ray Telescope for a 3600 square degree field of view. The sensor uses lobster-eye micropore optics; it is the first space telescope that uses such optics. In 2022 August and September, LEIA carried out a series of test observations for several days as part of its performance verification phase. A number of preselected sky regions and targets were observed, including the Galactic Center, the Magellanic Clouds, Sco X-1, Cas A, Cygnus Loop, and a few extragalactic sources. The observa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Be–white Dwarf X-ray Binary System
Be–white dwarf X-ray binary systems (BeWDs) are a rare type of X-ray binary consisting of a white dwarf that accretes matter from a rapidly-rotating Be star. These systems form through binary evolution where mass transfer spins up the accretor to become a Be star while the donor evolves into a white dwarf. BeWDs probably originate from a Be star and a Subdwarf O star, subdwarf O or Subdwarf B star, B star binaries. Population synthesis models indicate these systems can evolve through two primary pathways: * Approximately 60-70% merge into red giants that observationally look like luminous red novae. * About 30-40% evolve into double white dwarf systems that may be detectable as gravitational wave sources by Laser Interferometer Space Antenna (LISA), and will be its "most likely gravitational wave source". The formation requires specific initial conditions: the primary must transfer sufficient mass to spin up the secondary to Be star velocities without triggering common envelope e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma-ray Burst
In gamma-ray astronomy, gamma-ray bursts (GRBs) are extremely energetic events occurring in distant Galaxy, galaxies which represent the brightest and most powerful class of explosion in the universe. These extreme Electromagnetic radiation, electromagnetic emissions are second only to the Big Bang as the most energetic and luminous phenomenon ever known. Gamma-ray bursts can last from a few milliseconds to several hours. After the initial flash of gamma rays, a longer-lived afterglow is emitted, usually in the longer wavelengths of X-ray, ultraviolet, visible spectrum, optical, infrared, microwave or radio waves, radio frequencies. The intense radiation of most observed GRBs is thought to be released during a supernova or superluminous supernova as a high-mass star implodes to form a neutron star or a black hole. Short-duration (sGRB) events are a subclass of GRB signals that are now known to originate from the cataclysmic Neutron star merger, merger of binary neutron stars. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Burst
X-ray bursters are one class of X-ray binary stars exhibiting X-ray bursts, periodic and rapid increases in luminosity (typically a factor of 10 or greater) that peak in the X-ray region of the electromagnetic spectrum. These astrophysical systems are composed of an accreting neutron star and a main sequence companion 'donor' star. There are two types of X-ray bursts, designated I and II. Type I bursts are caused by thermonuclear runaway, while type II arise from the release of gravitational (potential) energy liberated through accretion. For type I (thermonuclear) bursts, the mass transferred from the donor star accumulates on the surface of the neutron star until it ignites and fuses in a burst, producing X-rays. The behaviour of X-ray bursters is similar to the behaviour of recurrent novae. In the latter case the compact object is a white dwarf that accretes hydrogen that finally undergoes explosive burning. The compact object of the broader class of X-ray binaries is either ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bright X-ray Flare
Bright may refer to: Common meanings *Bright, an adjective meaning giving off or reflecting illumination; see Brightness *Bright, an adjective meaning someone with intelligence People * Bright (surname) * Bright (given name) *Bright, the stage name of Thai actor, musician, model, host and entrepreneur Vachirawit Chivaaree Places Australia * Bright, Victoria, a town * Electoral district of Bright in South Australia Canada * Bright Parish, New Brunswick Northern Ireland * Bright, County Down, a village and parish in County Down United States * Bright, Indiana, a census-designated place * Bright, West Virginia, an unincorporated community * Bright, Wisconsin, an unincorporated community Arts and entertainment Music * Bright (American band), an experimental pop group from Brooklyn, New York ** ''Bright'' (Bright (American band) album), 1996 album *Bright (Japanese band), a dance vocal band from Japan ** ''Bright'' (Bright (Japanese band) album), 2012 album * "Bright" (song), a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Transient
X-ray emission occurs from many celestial objects. These emissions can have a pattern, occur intermittently, or as a transient astronomical event. In X-ray astronomy many sources have been discovered by placing an X-ray detector above the Earth's atmosphere. Often, the first X-ray source discovered in many constellations is an X-ray transient. These objects show changing levels of X-ray emission. NRL astronomer Dr. Joseph Lazio stated: " ... the sky is known to be full of transient objects emitting at X- and gamma-ray wavelengths, ...". There are a growing number of recurrent X-ray transients. In the sense of traveling as a transient, the only stellar X-ray source that does not belong to a constellation is the Sun. As seen from Earth, the Sun moves from west to east along the ecliptic, passing over the course of one year through the twelve constellations of the Zodiac, and Ophiuchus. Exotic X-ray transients SCP 06F6 is (or was) an astronomical object of unknown type, discovered on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Earth Orbit
A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, peaking in number at an altitude around , while the farthest in LEO, before medium Earth orbit (MEO), have an altitude of 2,000 km, about one-third of the Earth radius, radius of Earth and near the beginning of the Van Allen radiation belt#Inner belt, inner Van Allen radiation belt. The term ''LEO region'' is used for the area of space below an altitude of (about one-third of Earth's radius). Objects in orbits that pass through this zone, even if they have an apogee further out or are sub-orbital spaceflight, sub-orbital, are carefully tracked since they present a collision risk to the many LEO satellites. No human spaceflights other than the lunar missions of the Apollo program (1968-1972) have gone beyond L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolter Telescope
A Wolter telescope is a telescope for X-rays that only uses grazing incidence optics – mirrors that reflect X-rays at very shallow angles. Problems with conventional telescope designs Conventional telescope designs require reflection or refraction in a manner that does not work well for X-rays. Visible light optical systems use either lenses or mirrors aligned for nearly normal incidence – that is, the light waves travel nearly perpendicular to the reflecting or refracting surface. Conventional mirror telescopes work poorly with X-rays, since X-rays that strike mirror surfaces nearly perpendicularly are either transmitted or absorbed – not reflected. Lenses for visible light are made of transparent materials with an index of refraction substantially different from 1, but all known X-ray-transparent materials have index of refraction essentially the same as 1, so a long series of X-ray lenses, known as compound refractive lenses, are required in order to achieve focusing wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EROSITA
eROSITA is an X-ray instrument built by the Max Planck Institute for Extraterrestrial Physics (MPE) in Germany. It is part of the Russian–German Spektr-RG space observatory, which also carries the Russian telescope ART-XC. It was launched by Roscosmos on 13 July 2019 from Baikonur, and deployed in a 6-month halo orbit around the second Lagrange point (L2). It began collecting data in October 2019. Due to the breakdown of institutional cooperation between Germany and Russia after the invasion of Ukraine, the instrument stopped collecting data on February 26, 2022. Overview eROSITA was originally designed by the ESA for the International Space Station, and it was concluded in 2005 that its accommodation on a dedicated free flyer would provide significantly improved scientific output. The eROSITA telescopes are based on the design of the ABRIXAS observatory launched in April 1999, whose battery was accidentally overcharged and destroyed three days after the mission star ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
