XEUS (X-ray Evolving Universe Spectroscopy) was a space observatory plan developed by the

European Space Agency The European Space Agency (ESA) is a 23-member International organization, international organization devoted to space exploration. With its headquarters in Paris and a staff of around 2,547 people globally as of 2023, ESA was founded in 1975 ...

(ESA) as a successor to the successful

XMM-Newton ''XMM-Newton'', also known as the High Throughput X-ray Spectroscopy Mission and the X-ray Multi-Mirror Mission, is an X-ray space observatory launched by the European Space Agency in December 1999 on an Ariane 5 rocket. It is the second corners ...

X-ray An X-ray (also known in many languages as Röntgen radiation) is a form of high-energy electromagnetic radiation with a wavelength shorter than those of ultraviolet rays and longer than those of gamma rays. Roughly, X-rays have a wavelength ran ...

satellite A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...

telescope A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using len ...

. It was merged to the

International X-ray Observatory The International X-ray Observatory (IXO) is a cancelled X-ray telescope that was to be launched in 2021 as a joint effort by NASA, the European Space Agency (ESA), and the Japan Aerospace Exploration Agency (JAXA). In May 2008, ESA and NASA e ...

(IXO) around 2008, but as that project ran into issues in 2011, the ESA component was forked off into

Advanced Telescope for High Energy Astrophysics Advanced Telescope for High-ENergy Astrophysics (''Athena'') is an X-ray observatory mission selected by European Space Agency (ESA) within its Cosmic Vision program to address the Hot and Energetic Universe scientific theme. ''Athena'' will o ...

(Athena). XEUS consisted of a mirror spacecraft that carried a large X-ray telescope, with a mirror area of about 5 m² and an imaging resolution better than 5 arcsec; for X-ray radiation with an energy of 1

keV In physics, an electronvolt (symbol eV), also written electron-volt and electron volt, is the measure of an amount of kinetic energy gained by a single electron accelerating through an electric potential difference of one volt in vacuum. When us ...

. A detector spacecraft would have flown in formation with the telescope at a distance of approximately 50 m, in the focus of the telescope. The detectors would have included a wide-field X-ray imager with an energy resolution of 150 eV at 6 keV, as well as a cryogenic narrow-field imager with an energy resolution of 2 eV at 1 keV. XEUS could have measured the X-ray spectrum and thereby the composition, temperature and velocities of hot matter in the early universe. It would address diverse questions like the origin and nature of black holes, their relation with star formation,

baryon In particle physics, a baryon is a type of composite particle, composite subatomic particle that contains an odd number of valence quarks, conventionally three. proton, Protons and neutron, neutrons are examples of baryons; because baryons are ...

s evolution, and the formation of the heavy elements in the Universe. The technology required for the follow-on project of XEUS, the

, eventually leading to

(

Athena Athena or Athene, often given the epithet Pallas, is an ancient Greek religion, ancient Greek goddess associated with wisdom, warfare, and handicraft who was later syncretism, syncretized with the Roman goddess Minerva. Athena was regarde ...

) which is currently under development. XEUS was one of the candidates for the Cosmic Vision programme of the European Space Agency.

Recent developments

In May 2008, ESA and

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

established a coordination group involving three agencies - ESA,

and

JAXA The 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 o ...

- with the intent of exploring a joint mission merging the ongoing XEUS and Constellation-X (Con-X) projects. This proposed the start of a joint study for the

(IXO).

References

External links

ESA International X-Ray Observatory Mission Site

Press Release
Micronit and Cosine Develop Next-Generation ESA X-ray Telescope
NASA International X-Ray Observatory Mission Site
{{DEFAULTSORT:Xeus European Space Agency space probes Cancelled spacecraft Space telescopes X-ray telescopes

Recent developments

See also

References

External links