![]() ![]() Shown here is the event in optical, ultraviolet and X-ray wavelengths. Main article: Supernova remnant Supernova 2005ke, which was detected in 2005, is a Type Ia supernova, an important "standard candle" explosion used by astronomers to measure distances in the universe. It has already been observed in gamma rays by the Energetic Gamma Ray Experiment Telescope (EGRET) also aboard the Compton Gamma Ray Observatory. ![]() QSO 0836+7107 is the faintest and most distant object to be observed in soft gamma rays. "What BATSE has discovered is that it can be a soft gamma-ray source", McCollough said. QSO 0836+7107 or 4C 71.07 was detected by BATSE as a source of soft gamma rays and hard X-rays. On board the Compton Gamma Ray Observatory (CGRO) is the Burst and Transient Source Experiment (BATSE) which detects in the 20 keV to 8 MeV range. These photons accelerate the electrons, which then emit X- and gamma-radiation via Compton and inverse Compton scattering. These electrons can also interact with visible light emitted by the disk around the AGN or the black hole at its center. This radio emission is caused by electrons spiraling (thus accelerating) along magnetic fields producing cyclotron or synchrotron radiation. QSO 0836+7107 is a Quasi- Stellar Object (QSO) that emits baffling amounts of radio energy. Its redshift of z=2.17, puts it about 11 billion years away in a 12 to 15-billion year-old universe (using z=1 as 5 billion light years).Ī quasi-stellar radio source ( quasar) is a very energetic and distant galaxy with an active galactic nucleus (AGN). 4C 71.07 is its designation in the Fourth Cambridge Survey of radio sources. It is in radio and in X-rays – and now, gamma rays – that this object really shines. In visible light, 4C 71.07 is less than impressive, just a distant speck of light. This helped convince scientists that they were studying data from the quasar and not some other source in the neighborhood. Main article: Quasar A view of 4C 71.07 from observations by the Burst and Transient Source Experiment. The galaxies and dark matter are collisionless and quickly become virialised, orbiting in the cluster potential well.Īt a statistical significance of 8σ, it was found that the spatial offset of the center of the total mass from the center of the baryonic mass peaks cannot be explained with an alteration of the gravitational force law. This very hot gas emits X-rays by thermal bremsstrahlung emission, and line emission from metals (in astronomy, 'metals' often means all elements except hydrogen and helium). The infalling gas collides with gas already in the cluster and is shock heated to between 10 7 and 10 8 K depending on the size of the cluster. The infalling material (which contains galaxies, gas and dark matter) gains kinetic energy as it falls into the cluster's gravitational potential well. Redshift ( z) = 0.3, meaning its light has wavelengths stretched by a factor of 1.3.Ĭlusters of galaxies are formed by the merger of smaller units of matter, such as galaxy groups or individual galaxies. Main article: Galaxy groups and clusters X-ray photo by Chandra X-ray Observatory of the Bullet Cluster. The X-ray continuum can arise from bremsstrahlung, either magnetic or ordinary Coulomb, black-body radiation, synchrotron radiation, inverse Compton scattering of lower-energy photons by relativistic electrons, knock-on collisions of fast protons with atomic electrons, and atomic recombination, with or without additional electron transitions. The origin of all observed astronomical X-ray sources is in, near to, or associated with a coronal cloud or gas at coronal cloud temperatures for however long or brief a period.Ī combination of many unresolved X-ray sources is thought to produce the observed X-ray background. Some Solar System bodies emit X-rays, the most notable being the Moon, although most of the X-ray brightness of the Moon arises from reflected solar X-rays.įurthermore, celestial entities in space are discussed as celestial X-ray sources. They include galaxy clusters, black holes in active galactic nuclei (AGN), galactic objects such as supernova remnants, stars, and binary stars containing a white dwarf ( cataclysmic variable stars and super soft X-ray sources), neutron star or black hole ( X-ray binaries). Several types of astrophysical objects emit X-rays. X-rays start at ~0.008 nm and extend across the electromagnetic spectrum to ~8 nm, over which Earth's atmosphere is opaque.Īstrophysical X-ray sources are astronomical objects with physical properties which result in the emission of X-rays. ![]()
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