XMM-Newton
Encyclopedia
The XMM-Newton is an orbiting X-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...

 observatory
Space observatory
A space observatory is any instrument in outer space which is used for observation of distant planets, galaxies, and other outer space objects...

 launched by ESA in December 1999 on a Ariane 5
Ariane 5
Ariane 5 is, as a part of Ariane rocket family, an expendable launch system used to deliver payloads into geostationary transfer orbit or low Earth orbit . Ariane 5 rockets are manufactured under the authority of the European Space Agency and the Centre National d'Etudes Spatiales...

 rocket. It is named in honor of Sir Isaac Newton
Isaac Newton
Sir Isaac Newton PRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived."...

.

Originally known as the High Throughput X-ray Spectroscopy Mission it was placed in a very eccentric 48 hour elliptical orbit at 40°; at its apogee it is nearly 114000 kilometres (70,836.5 mi) from Earth, while the perigee
Perigee
Perigee is the point at which an object makes its closest approach to the Earth.. Often the term is used in a broader sense to define the point in an orbit where the orbiting body is closest to the body it orbits. The opposite is the apogee, the farthest or highest point.The Greek prefix "peri"...

 is only 7000 kilometres (4,349.6 mi)

The satellite weighs 3800 kilograms (8,377.6 lb), is 10 metres (32.8 ft) long and 16 metres (52.5 ft) in span with its solar arrays deployed. It holds three X-ray telescopes, developed by Media Lario of Italy, each of which contains 58 Wolter-type concentric mirrors
Wolter telescope
A Wolter telescope is a telescope for X-rays using only grazing incidence optics. Visible light telescopes are built with lenses or parabolic mirrors at nearly normal incidence. Neither works well for X-rays. Lenses for visible light are made of a transparent material with an index of refraction...

. The combined collecting area is 4,300 cm². The three European Photon Imaging Cameras (EPIC) are sensitive over the energy range 0.2 keV
Kev
Kev can refer to:*Kev Hawkins, a fictional character.*Kevin, a given name occasionally shortened to "Kev".*Kiloelectronvolt, a unit of energy who symbol is "KeV".* Krefelder Eislauf-VereinKEV can refer to:...

 to 12 keV. Other instruments onboard are two reflection grating spectrometer
Spectrometer
A spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. The variable measured is most often the light's intensity but could also, for instance, be the polarization...

s which are sensitive below ~2 keV, and a 30 centimetres (11.8 in) diameter Ritchey-Chretien
Ritchey-Chrétien telescope
A Ritchey–Chrétien telescope is a specialized Cassegrain telescope designed to eliminate coma, thus providing a large field of view compared to a more conventional configuration. An RCT has a hyperbolic primary and a hyperbolic secondary mirror. It was invented in the early 1910s by American...

 optical/UV telescope.

The mission was proposed in 1984 and approved in 1985; a project team was formed in 1993 and development work began in 1996. The satellite was constructed and tested from March 1997 to September 1999. Launched in Dec 1999, in-orbit commissioning started Jan 2000. First images published Feb 2000.
The original mission lifetime was two years, it has now been extended for further observations until at least 2010, and again until 2012, and technically could operate until 2018.

Observations are managed and archived at the European Space Astronomy Centre (formerly known as VILSPA
VILSPA
The European Space Astronomy Centre is the ESA's centre for space science, which means Astronomy as well as Solar System exploration...

) at Villafranca, Spain. The data are processed at the XMM-Newton Survey Science Centre at the University of Leicester
University of Leicester
The University of Leicester is a research-led university based in Leicester, England. The main campus is a mile south of the city centre, adjacent to Victoria Park and Wyggeston and Queen Elizabeth I College....

, England.

The European satellite XMM-Newton (X-ray Multi Mirror), built under contract to ESA by a consortium of 35 European companies with Astrium as prime contractor, by far excels its predecessor, the Astrium-built ROSAT
ROSAT
ROSAT was a German Aerospace Center-led satellite X-ray telescope, with instruments built by Germany, the UK and the US...

 satellite.

Observations and discoveries

The observational scope of XMM Newton includes the detection of X-ray emissions from Solar System objects, detailed studies of star-forming regions, investigation of the formation and evolution of galaxy clusters, the environment of supermassive black holes and the mapping of the mysterious "dark matter".

It was used to discover the 10 billion light years from Earth galaxy cluster
Galaxy cluster
A galaxy cluster is a compact cluster of galaxies. Basic difference between a galaxy group and a galaxy cluster is that there are many more galaxies in a cluster than in a group. Also, galaxies in a cluster are more compact and have higher velocity dispersion. One of the key features of cluster is...

 XMMXCS 2215-1738
XMMXCS 2215-1738
XMMXCS 2215-1738 is a galaxy cluster that lies 10 billion light-years away, or redshift z=1.45 . It was discovered by the XMM Cluster Survey in 2006....

, as well as the 7-billion light year away 2XMM J083026+524133 

The object SCP 06F6
SCP 06F6
SCP 06F6 is an astronomical object of unknown type, discovered on 21 February 2006 in the constellation Boötesduring a survey of galaxy cluster CL 1432.5+3332.8 with the Hubble Space Telescope's Advanced Camera for Surveys Wide Field Channel....

 discovered by the Hubble Space Telescope
Hubble Space Telescope
The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation. A 2.4 meter aperture telescope in low Earth orbit, Hubble's four main instruments observe in the near ultraviolet, visible, and near infrared...

(HST) in February 2006 was then observed by XMM Newton in early August 2006, and appeared to show an X-ray glow around it two orders of magnitude more luminous than that of supernovae.

In June 2011, a team from the University of Geneva
University of Geneva
The University of Geneva is a public research university located in Geneva, Switzerland.It was founded in 1559 by John Calvin, as a theological seminary and law school. It remained focused on theology until the 17th century, when it became a center for Enlightenment scholarship. In 1873, it...

, Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

, reported XMM-Newton seeing a flare that lasted four hours at a peak intensity of 10,000 times the normal rate, from an observation of Supergiant Fast X-Ray Transient IGR J18410-0535, where a blue supergiant
Blue supergiant
Blue supergiants are supergiant stars of spectral type O or B.They are extremely hot and bright, with surface temperatures of 30,000-50,000 K. They typically have 10 to 50 solar masses on the Hertzsprung-Russell diagram, and can have radii up to about 25 solar radii...

 star shed a plume of matter that was partly ingested by the smaller neutron star
Neutron star
A neutron star is a type of stellar remnant that can result from the gravitational collapse of a massive star during a Type II, Type Ib or Type Ic supernova event. Such stars are composed almost entirely of neutrons, which are subatomic particles without electrical charge and with a slightly larger...

 with the accompanying X-ray emissions.

Details of the telescopes

Each telescope consists of 58 600mm-long shells, with diameters from 306 to 700 millimetres, and thickness linearly dependent on the diameter increasing from 470 µm at the small shells to 1070 µm at the large one; the fully assembled telescope has gaps of about one millimetre between the shells. The shells are made by electroforming
Electroforming
Electroforming is a metal forming process that forms thin parts through the electroplating process. The part is produced by plating a metal skin onto a base form, known as a mandrel, which is removed after plating...

 onto a highly polished aluminium mandrel
Mandrel
A mandrel is one of the following:* an object used to shape machined work.* a tool component that grips or clamps materials to be machined.* a tool component that can be used to grip other moving tool components.- Variants :...

, starting with a 250 nm layer of vapour-deposited gold that becomes the reflecting surface, then the nickel support; the mandrels are reusable but a different one is needed for each shell. The electroforming deposits nickel at a rate of 10 µm per hour. The mandrels were manufactured at Carl Zeiss
Carl Zeiss
Carl Zeiss was a German maker of optical instruments commonly known for the company he founded, Carl Zeiss Jena . Zeiss made contributions to lens manufacturing that have aided the modern production of lenses...

, and the electroforming and final assembly performed at Media Lario; Kayser-Threde
Kayser-Threde
Kayser-Threde GmbH based in Munich, Germany is a systems house specializing in the design and development of high-technology solutions for astronautics, science and the industry...

 also played a role.

The shells are glued into grooves in an Inconel
Inconel
Inconel is a registered trademark of Special Metals Corporation that refers to a family of austenitic nickel-chromium-based superalloys. Inconel alloys are typically used in high temperature applications. It is often referred to in English as "Inco"...

spider, which keeps them aligned to within the five-micron tolerance required to get adequate X-ray resolution.

External links

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