ESA in the context of "International organisation"

The Chandra X-ray Observatory (CXO), previously known as the Advanced X-ray Astrophysics Facility (AXAF), is a Flagship-class space telescope launched aboard the Space Shuttle Columbia during STS-93 by NASA on July 23, 1999. Chandra is sensitive to X-ray sources 100 times fainter than any previous X-ray telescope, enabled by the high angular resolution of its mirrors. Since the Earth's atmosphere absorbs the vast majority of X-rays, they are not detectable from Earth-based telescopes; therefore space-based telescopes are required to make these observations. Chandra is an Earth satellite in a 64-hour orbit, and its mission is ongoing as of 2025. Chandra is one of the Great Observatories, along with the Hubble Space Telescope, Compton Gamma Ray Observatory (1991–2000), and the Spitzer Space Telescope (2003–2020). The telescope is named after the Nobel Prize-winning Indian-American astrophysicist Subrahmanyan Chandrasekhar. Its mission is similar to that of ESA's XMM-Newton spacecraft, also launched in 1999 but the two telescopes have different design foci, as Chandra has a much higher angular resolution and XMM-Newton higher spectroscopy throughput.

In response to a decrease in NASA funding in 2024 by the US Congress, Chandra is threatened with an early cancellation despite having more than a decade of operation left. The cancellation has been referred to as a potential "extinction-level" event for X-ray astronomy in the US. A group of astronomers have put together a public outreach project to try to get enough American citizens to persuade the US Congress to provide enough funding to avoid early termination of the observatory.

The Cupola is an ESA-built observatory module of the International Space Station (ISS). Its name derives from the Italian word cupola, which means "dome". Its seven windows are used to conduct experiments, dockings and observations of Earth. It was launched aboard Space Shuttle Endeavour's mission STS-130 on 8 February 2010, and attached to the Tranquility (Node 3) module. With the Cupola attached, ISS assembly reached 85 percent completion. The Cupola's central window has a diameter of 80 cm (31 in).

Neptune has been directly explored by one space probe, Voyager 2, in 1989. As of 2025, there are no confirmed future missions to visit the Neptunian system. NASA, ESA, CNSA and independent academic groups have proposed future scientific missions to visit Neptune. Some mission plans are still active, while others have been abandoned or put on hold.

Since the mid-1990s, Neptune has been studied from afar with telescopes, including the Hubble Space Telescope and the ground-based Keck telescope using adaptive optics.

A starburst galaxy is one undergoing an exceptionally high rate of star formation, as compared to the long-term average rate of star formation in the galaxy, or the star formation rate observed in most other galaxies.

For example, the star formation rate of the Milky Way galaxy is approximately 3 M_☉/yr, while starburst galaxies can experience star formation rates of 100 M_☉/yr or more. In a starburst galaxy, the rate of star formation is so large that the galaxy consumes all of its gas reservoir, from which the stars are forming, on a timescale much shorter than the age of the galaxy. As such, the starburst nature of a galaxy is a phase, and one that typically occupies a brief period of a galaxy's evolution. The majority of starburst galaxies are in the midst of a merger or close encounter with another galaxy. Starburst galaxies include M82, NGC 4038/NGC 4039 (the Antennae Galaxies), and IC 10.

STS-122 was a NASA Space Shuttle mission to the International Space Station (ISS), flown by the Space Shuttle Atlantis. STS-122 marked the 24th shuttle mission to the ISS, and the 121st Space Shuttle flight overall.

The mission was also referred to as ISS-1E by the ISS program. The primary objective of STS-122 was to deliver the European Columbus science laboratory, built by the European Space Agency (ESA), to the station. It also returned Expedition 16 Flight Engineer Daniel M. Tani to Earth. Tani was replaced on Expedition 16 by Léopold Eyharts, a French Flight Engineer representing ESA. After Atlantis landing, the orbiter was prepared for STS-125, the final servicing mission for the Hubble Space Telescope.

Flight controllers are personnel who aid space flight by working in mission control centers such as NASA's Christopher C. Kraft Jr. Mission Control Center or ESA's European Space Operations Centre. Flight controllers work at computer consoles and use telemetry to monitor various technical aspects of a space mission in real-time. Each controller is an expert in a specific area and constantly communicates with additional experts in the "back room". The flight director, who leads the flight controllers, monitors the activities of a team of flight controllers, and has overall responsibility for success and safety.

The Satellite Catalog Number (SATCAT), also known as NORAD Catalog Number, NORAD ID, USSPACECOM object number, is a sequential five-digit number assigned by the United States Space Command (USSPACECOM), and previously the North American Aerospace Defense Command (NORAD), in the order of launch or discovery to all artificial objects in the orbits of Earth and those that left Earth's orbit. For example, catalog number 1 is the Sputnik 1 launch vehicle, with the Sputnik 1 satellite having been assigned catalog number 2.

Objects that fail to orbit or orbit for a short time are not catalogued. The minimum object size in the catalog is 10 centimetres (3.9 in) in diameter. As of October 21, 2023, the catalog listed 58,010 objects, including 16,645 satellites that had been launched into orbit since 1957 of which 8,936 were still active. 25,717 of the objects were well tracked while 2,055 were lost. In addition USSPACECOM was also tracking 16,600 analyst objects. Analyst objects are variably tracked and in constant flux, so their catalog and element set data are not published. As of September 12, 2023 ESA estimated there were about 36,500 pieces of orbiting debris that are large enough for USSPACECOM to track.

Concordia Research Station, which opened in 2005, is a French–Italian research facility managed by l'Institut polaire français Paul-Émile Victor and Programma Nazionale di Ricerche in Antartide, that was built 3,233 m (10,607 ft) above sea level on a geographical formation known as dôme C, on the Antarctic Plateau, Antarctica. It is located 1,100 km (680 mi) inland from the French research station at Dumont D'Urville, 1,100 km (680 mi) inland from Australia's Casey Station and 1,200 km (750 mi) inland from the Italian Zucchelli Station at Terra Nova Bay. Russia's Vostok Station is 560 km (350 mi) away. The Geographic South Pole is 1,670 km (1,040 mi) away. The facility is also located within Australia's claim on Antarctica, the Australian Antarctic Territory.

Concordia Station is the third permanent, all-year research station on the Antarctic Plateau besides Vostok Station and the Amundsen–Scott South Pole Station (U.S.) at the Geographic South Pole. It is jointly operated by scientists from France and Italy and regularly hosts ESA scientists.

The Hubble Deep Field South is a composite of several hundred individual images taken using the Hubble Space Telescope's Wide Field and Planetary Camera 2 over 10 days in September and October 1998. It followed the great success of the original Hubble Deep Field in facilitating the study of extremely distant galaxies in early stages of their evolution. While the WFPC2 took very deep optical images, nearby fields were simultaneously imaged by the Space Telescope Imaging Spectrograph (STIS) and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS).