Space Telescope Science Institute
   HOME

TheInfoList



OR:

The Space Telescope Science Institute (STScI) is the science operations center for the
Hubble Space Telescope The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versa ...
(HST), science operations and mission operations center for the James Webb Space Telescope (JWST), and science operations center for the
Nancy Grace Roman Space Telescope The Nancy Grace Roman Space Telescope (shortened as Roman or the Roman Space Telescope, and formerly the Wide-Field Infrared Survey Telescope or WFIRST) is a NASA infrared space telescope currently in development and scheduled to launch by Ma ...
. STScI was established in 1981 as a community-based science center that is operated for
NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...
by the
Association of Universities for Research in Astronomy The Association of Universities for Research in Astronomy (AURA) is a consortium of universities and other institutions that operates astronomical observatories and telescopes. Founded October 10, 1957, with the encouragement of the National Sc ...
(AURA). STScI's offices are located on the
Johns Hopkins University Johns Hopkins University (Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland. Founded in 1876, Johns Hopkins is the oldest research university in the United States and in the western hem ...
Homewood Campus The Homewood Campus is the main academic and administrative center of the Johns Hopkins University. It is located at 3400 North Charles Street in Baltimore, Maryland. It houses the two major undergraduate schools: the Zanvyl Krieger School of Arts ...
and in the Rotunda building in
Baltimore Baltimore ( , locally: or ) is the List of municipalities in Maryland, most populous city in the U.S. state of Maryland, fourth most populous city in the Mid-Atlantic (United States), Mid-Atlantic, and List of United States cities by popula ...
,
Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...
. In addition to performing continuing science operations of HST and preparing for scientific exploration with JWST and Roman, STScI manages and operates the
Mikulski Archive for Space Telescopes The Mikulski Archive for Space Telescopes (MAST) is an astronomical data archive. The archive brings together data from the visible, ultraviolet, and near-infrared wavelength regimes. The NASA funded project is located at the Space Telescope Scie ...
(MAST), which holds data from numerous active and legacy missions, including HST, JWST,
Kepler Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws o ...
,
TESS Tess or TESS may refer to: Music * Tess (band), a Spanish pop band active from 2000 to 2005 * TESS (musician), a UK musician Film and theatre * ''Tess'' (1979 film), a 1979 film adaptation of '' Tess of the d'Urbervilles'' * ''Tess'' (2016 film ...
,
Gaia In Greek mythology, Gaia (; from Ancient Greek , a poetical form of , 'land' or 'earth'),, , . also spelled Gaea , is the personification of the Earth and one of the Greek primordial deities. Gaia is the ancestral mother—sometimes parthenog ...
, and
Pan-STARRS The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1; obs. code: F51 and Pan-STARRS2 obs. code: F52) located at Haleakala Observatory, Hawaii, US, consists of astronomical cameras, telescopes and a computing facility that is ...
. Most of the funding for STScI activities comes from contracts with NASA's
Goddard Space Flight Center The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory located approximately northeast of Washington, D.C. in Greenbelt, Maryland, United States. Established on May 1, 1959 as NASA's first space flight center, GSFC empl ...
but there are smaller activities funded by NASA's
Ames Research Center The Ames Research Center (ARC), also known as NASA Ames, is a major NASA research center at Moffett Federal Airfield in California's Silicon Valley. It was founded in 1939 as the second National Advisory Committee for Aeronautics (NACA) laborat ...
, NASA's
Jet Propulsion Laboratory The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States. Founded in the 1930s by Caltech researchers, JPL is owned by NASA an ...
, and the
European Space Agency , owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (1205 ...
(ESA). The staff at STScI consists of scientists (mostly astronomers and astrophysicists), spacecraft engineers, software engineers, data management personnel, education and public outreach experts, and administrative and business support personnel. There are approximately 100 Ph.D. scientists working at STScI, 15 of whom are ESA staff who are on assignment to the HST project. The total STScI staff consists of about 850 people as of 2021. STScI operates its missions on behalf of NASA, the worldwide astronomy community, and to the benefit of the public. The science operations activities directly serve the astronomy community, primarily in the form of and (and eventually Roman) observations and grants, but also include distributing data from other NASA and ground-based missions via MAST. The ground system development activities create and maintain the software systems that are needed to provide these services to the astronomy community. STScI's public outreach activities provide a wide range of resources for media, informal education venues such as planetariums and science museums, and the general public. STScI also serves as a source of guidance to NASA on a range of optical and UV space astrophysics issues. The STScI staff interacts and communicates with the professional astronomy community through a number of channels, including participation at the bi-annual meetings of the American Astronomical Society, publication of regular STScI newsletters and the STScI website, hosting user committees and science working groups, and holding several scientific and technical symposia and workshops each year. These activities enable STScI to disseminate information to the telescope user community as well as enabling the STScI staff to maximize the scientific productivity of the facilities they operate by responding to the needs of the community and of NASA.


STScI activities

''Note: Information in this section needs updating. For current activities, consult STScI's official website.''


Telescope science proposal selection

The STScI conducts all activities required to select, schedule, and implement the science programs of the Hubble Space Telescope. The first step in this process is to support the annual community-led selection of the scientific programs that will be performed with HST. This begins with publishing of the annual Call for Proposals, which specifies the currently supported science instrument capabilities, proposal requirements and the submission deadline. Anyone is eligible to submit a proposal. All proposals are critically peer-reviewed by the Time Allocation Committee (TAC). The TAC consists of about 100 members of the U.S. and international astronomical community, selected to represent a broad range of research expertise needed to evaluate the proposals. Each proposal cycle typically involves reviewing 700 to 1100 proposals. Only 15 - 20% of these proposals will eventually be selected for implementation. The TAC reviews several categories of observing time, as well as proposals for archival, theoretical, and combined research projects between HST and other space-based or ground-based observatories (e.g.,
Chandra X-ray Observatory 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 during STS-93 by NASA on July 23, 1999. Chandra is sensitive to X-ray sources 1 ...
and the
National Optical Astronomy Observatories The National Optical Astronomy Observatory (NOAO) was the United States national observatory for ground-based nighttime ultraviolet-optical-infrared (OUVIR) astronomy. The National Science Foundation (NSF) funded NOAO to provide forefront astronom ...
). STScI provides all technical and logistical support for these activities. The annual cycle of proposal calls was occasionally altered in duration in years when a HST servicing mission was scheduled. Proposers fortunate enough to be awarded telescope time, referred to as General Observers (GOs), must then provide detailed requirements needed to schedule and implement their observing programs. This information is provided to STScI on what is called a Phase II proposal. The Phase II proposal specifies instrument operation modes, exposure times, telescope orientations, and so on. The STScI staff provide the web-based software calle
Exposure Time Calculators
(ETCs) that allow GOs to estimate how much observing time any of the onboard detectors will need to accumulate the amount of light required to accomplish their scientific objectives. In addition, the STScI staff carries out all the steps necessary to implement each specific program, as well as plan the entire ensemble of programs for the year. For HST, this includes finding guide stars, checking on bright object constraints, implementing specific scheduling requirements, and working with observers to understand and factor in specific or any non-standard requirements they may have.


Observation scheduling

Once the Phase II information is gathered, a long-range observing plan is developed that covers the entire year, finding appropriate times to schedule individual observations, and at the same time ensuring effective and efficient use of the telescope through the year. Detailed observing schedules are created each week, including, in the case of HST operations, scheduling the data communication paths via the Tracking and Data Relay Satellite System (
TDRSS The U.S. Tracking and Data Relay Satellite System (TDRSS) is a network of American communications satellites (each called a tracking and data relay satellite, TDRS) and ground stations used by NASA for space communications. The system was desig ...
) and generating the binary command loads for uplink to the spacecraft. Adjustments can be made to both long-range and weekly plans in response to Targets of Opportunity (e.g., for transient events like
supernova A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...
e or coordination with one-of-a-kind events such as
comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ar ...
impact spacecraft). The STScI uses the
Min-conflicts algorithm In computer science, the min-conflicts algorithm is a search algorithm or heuristic method to solve constraint satisfaction problems. Given an initial assignment of values to all the variables of a constraint satisfaction problem, the algorithm r ...
to schedule observation time on the telescope. The STScI is currently developing similar processes for JWST, although the operational details will be very different due to its different instrumentation and spacecraft constraints, and its location at the Sun-Earth L2 Lagrange point (~1.5 million km from Earth) rather than the low Earth orbit (~565 km) used by HST.


Flight operations

Flight Operations consists of the direct support and monitoring of HST functions in real-time. Real-time daily flight operations for HST include about 4 command load uplinks, about 10 data downlinks, and near continuous health and safety monitoring of the observatory. Real-time operations are staffed around the clock. Flight operations activities for HST are done at NASA's GSFC in Greenbelt, Maryland.


Science data processing

Science data from HST arrive at the STScI a few hours after being downlinked from TDRSS and subsequently passing through a data capture facility at NASA's Goddard Space Flight Center. Once at STScI, the data are processed by a series of computer algorithms that convert its format into an internationally accepted standard (known as FITS: Flexible Image Transport System), correct for missing data, and perform final calibration of the data by removing instrumental artifacts. The calibration steps are different for each HST instrument, but as a general rule they include cosmic ray removal, correction for instrument/detector non-uniformities, flux calibration, and application of world coordinate system information (which tells the user precisely where on the sky the detector was pointed). The calibrations applied are the best available at the time the data pass through the pipeline. The STScI is working with instrument developers to define similar processes for
Kepler Johannes Kepler (; ; 27 December 1571 – 15 November 1630) was a German astronomer, mathematician, astrologer, natural philosopher and writer on music. He is a key figure in the 17th-century Scientific Revolution, best known for his laws o ...
and JWST data.


Science data archiving and distribution

All HST science data are permanently archived after passing through the calibration pipeline. NASA policy mandates a one-year proprietary period on all data, which means that only the initial proposal team can access the data for the first year after it has been obtained. Subsequent to that year, the data become available to anyone who wishes to access it. Data sets retrieved from the archive are automatically re-calibrated to ensure that the most up-to-date calibration factors and software are applied. The STScI serves as the archive center for all of NASA's optical/UV space missions. In addition to archiving and storing HST science data, STScI holds data from 13 other missions including the
International Ultraviolet Explorer International Ultraviolet Explorer (IUE or Explorer 57, formerly SAS-D), was the first space observatory primarily designed to take ultraviolet (UV) electromagnetic spectrum. The satellite was a collaborative project between NASA, the United K ...
(IUE), the
Extreme Ultraviolet Explorer The Extreme Ultraviolet Explorer (EUVE or Explorer 67) was a NASA space telescope for ultraviolet astronomy. EUVE was a part of NASA's Explorer spacecraft series. Launched on 7 June 1992. With instruments for ultraviolet (UV) radiation between ...
(EUVE), the
Far Ultraviolet Spectroscopic Explorer Far Ultraviolet Spectroscopic Explorer (FUSE, Explorer 77, and MIDEX-0) represented the next generation, high-orbit, ultraviolet space observatory covering the wavelength range of 90.5–119.5 nanometre (nm) of the NASA operated by the Johns H ...
(FUSE), and the
Galaxy Evolution Explorer Galaxy Evolution Explorer (GALEX or Explorer 83 or SMEX-7) was a NASA orbiting space telescope designed to observe the universe in ultraviolet wavelengths to measure the history of star formation in the universe. In addition to paving the way ...
(GALEX). Kepler and JWST science data will be archived and retrieved in similar fashions. The internet serves as the primary user interface to the data archives at STScI (http://archive.stsci.edu). The archive currently holds over 30
terabyte The byte is a units of information, unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character (computing), character of text in a computer and for this ...
s of data. Each day about 11 gigabytes of new data are ingested and about 85 gigabytes of data are distributed to users. The Hubble Legacy Archive (HLA; http://hla.stsci.edu/), currently in development, will act as a more integrated and user-friendly archive. It will provide raw Hubble data as well as higher-level science products (color images, mosaics, etc.).


Science instrument calibration and characterization

STScI is responsible for in-flight calibration of the science instruments on HST and JWST. For HST, a calibration plan for the observatory is developed each year. This plan is designed to support the selected GO observation programs for that cycle, as well as to provide a basic calibration that spans the lifetime of each instrument. The calibration program includes measurements that are made relative to on-board calibration sources or to assess internal detector noise levels as well as observations of astronomical standard stars and fields, needed to determine absolute flux conversions and astrometric transformations. The external calibrations on HST typically total 5-10% of the GO observing program, with more time required when an instrument is still relatively new. HST has had a total of 12 science instruments to date, 6 of which are currently active. Two new instruments were installed during the May 2009 HST servicing mission
STS-125 STS-125, or HST-SM4 (Hubble Space Telescope Servicing Mission 4), was the fifth and final Space Shuttle mission to the Hubble Space Telescope (HST) and the last solo flight of the Space Shuttle Atlantis, Space Shuttle ''Atlantis''. The launch of ...
. Electronic failures in STIS (in 2001) and in the ACS Wide-Field Channel (in 2007) were also repaired on-orbit in May 2009, bringing these instruments back to active status. All 12 HST instruments plus the 4 planned for JWST are summarized in the table below. HST instruments can detect light with wavelengths from the
ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nanometer, nm (with a corresponding frequency around 30 Hertz, PHz) to 400 nm (750 Hertz, THz), shorter than that of visible light, but longer than ...
through the near
infrared Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
. JWST instruments will operate from the red-end of optical wavelengths (~6000 Angstroms) to the mid-infrared (5 to 27 micrometres). Instruments listed as decommissioned are no longer on board. STScI staff develops the calibration proposals, shepherd them through the scheduling process, and analyze the data they produce. These programs provide updated calibration and reference files to be used in the data processing pipeline. The calibration files are also archived so users can retrieve them if they need to manually recalibrate their data. All calibration activity and results are documented, usually in the form of Instrument Science Reports posted to the public website, and occasionally in the form of published papers. Results are also incorporated into the Data Handbooks and Instrument Handbooks. In addition to calibration of the instruments, STScI staff characterizes and documents the performance of the instrument, so users can better understand how to interpret their data. These are generally effects that are not automatically corrected for in the pipeline (because they vary with time or depend on the brightness of the source). They include global effects, such as charge transfer efficiency in the
charge-coupled device A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a ...
s, as well as effects specific to modes and filters, such as filter "ghosts" (caused by subtle scattering of light within an instrument). Awareness of these effects can come from STScI staff as they analyze calibration programs, or from observers who find oddities in their data and provide feedback to STScI. The STScI staff also performs the characterization and calibration of the telescope itself. In the case of HST, this has evolved to primarily be a matter of monitoring and adjusting focus, and monitoring and measuring point spread functions. (In the early 1990s, the STScI was responsible for accurate measurement of the
spherical aberration In optics, spherical aberration (SA) is a type of optical aberration, aberration found in optical systems that have elements with spherical surfaces. Lens (optics), Lenses and curved mirrors are prime examples, because this shape is easier to man ...
, necessary for the corrective optics of all subsequent instruments). In the case of JWST, the STScI will be responsible for using the
wavefront sensor In physics, the wavefront of a time-varying ''wave field'' is the set (locus) of all points having the same '' phase''. The term is generally meaningful only for fields that, at each point, vary sinusoidally in time with a single temporal frequ ...
system developed by JPL and
Northrop Grumman Northrop Grumman Corporation is an American multinational aerospace and defense technology company. With 90,000 employees and an annual revenue in excess of $30 billion, it is one of the world's largest weapons manufacturers and military techn ...
Space Technology (NGST, the NASA contractor building the observatory) to monitor and adjust the segmented telescope.


Post observation support

The post observation support includes a HelpDesk that users can contact to answer their questions about any aspect of observing – from how to submit a proposal to how to analyze the data.


Science community service

The STScI performs large HST science programs on behalf of the community. These are programs with broad scientific applications. To date, these programs include the
Hubble Deep Field The Hubble Deep Field (HDF) is an image of a small region in the constellation Ursa Major, constructed from a series of observations by the Hubble Space Telescope. It covers an area about 2.6 arcminutes on a side, about one 24-millionth of the ...
(HDF), the
Hubble Deep Field South 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 ...
(HDFS), and the
Ultra Deep Field The Hubble Ultra-Deep Field (HUDF) is a List of deep fields, deep-field image of a small region of outer space, space in the constellation Fornax, containing an estimated 10,000 galaxies. The original data for the image was collected by the Hub ...
(UDF). The raw and processed data for these observations are made available to the astronomy community nearly immediately. These products have then been used by many astronomers in pursuit of their own research topics, and have motivated a great deal of follow-up work (see, for example, http://www.stsci.edu/ftp/science/hdf/clearinghouse/clearinghouse.html and http://www.stsci.edu/hst/udf/index_html).


Ground systems

STScI is responsible for developing, enhancing, and maintaining most of the ground systems used to carry out our Hubble science operations described above. These systems originally (1980s, early 1990s) came from several sources, including in-house STScI developments and work done under NASA contracts with various vendors. Over HST's lifetime substantial work has been done on these systems - even while they were supporting daily operations of Hubble. They have been integrated into a more effective and easier to operate end-to-end system. They have been through major technology upgrades (e.g., improved operating systems and computer hardware, higher capacity archive storage media). They have also been modified to support the succession of instruments installed in the telescope. In the last several years, they have been modified to support WFC3 and COS, the two new instruments that will be installed during the next HST servicing mission, and to support the 2-
Gyroscope A gyroscope (from Ancient Greek γῦρος ''gŷros'', "round" and σκοπέω ''skopéō'', "to look") is a device used for measuring or maintaining orientation and angular velocity. It is a spinning wheel or disc in which the axis of rota ...
mode of HST operations. STScI also provides subsets of ground system services to other astronomy missions, including FUSE, Kepler, and JWST. STScI's software engineers maintain about 7,900,000
source lines of code Source lines of code (SLOC), also known as lines of code (LOC), is a software metric used to measure the size of a computer program by counting the number of lines in the text of the program's source code. SLOC is typically used to predict the am ...
.


Mission development and operations support

STScI routinely participates with NASA and industry system engineers and scientists in developing the overall mission architecture. For HST, this includes helping to determine and prioritize servicing mission activities and development of the servicing strategy. For JWST, this includes participating in the definition of high-level science requirements and the overall architecture for the mission. In both cases, the STScI focuses on the scientific capabilities of the mission, and also the requirements for smooth and efficient operations of the observatory.


Scientific research activities

STScI manages the selection of the Hubble Fellowship Program. Since 1990, Hubble Fellowships support outstanding postdoctoral scientists whose research is broadly related to the scientific mission of the Hubble Space Telescope. In 2009, it was combined with the Spitzer Fellowship that since 2002 had been associated with the Spitzer Space Telescope and science program. It now supports fellows undertaking research associated with all missions within the Cosmic Origins theme: the
Herschel Space Observatory The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA). It was active from 2009 to 2013, and was the largest infrared telescope ever launched until the launch of the James Webb Space Telesc ...
, Hubble Space Telescope (HST), James Webb Space Telescope (JWST), Stratospheric Observatory for Infrared Astronomy (SOFIA), and the Spitzer Space Telescope. The research may be theoretical, observational, or instrumental. Each year, since HST's launch in 1990, 8 to 12 fellowships are awarded; from 2009 it hovers about 16. STScI also sponsors a summer student intern program that allows talented undergraduate students from around the world to work with the institute's scientific staff, providing these students with hands-on experience in state-of-the-art astronomical research. STScI's full-time scientific staff conducts original research spanning a broad range of astrophysics including investigations of the
Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar S ...
,
exoplanet An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, init ...
detection and characterization,
star formation Star formation is the process by which dense regions within molecular clouds in The "medium" is present further soon.-->interstellar space
,
galaxy A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. ...
evolution, and
physical cosmology Physical cosmology is a branch of cosmology concerned with the study of cosmological models. A cosmological model, or simply cosmology, provides a description of the largest-scale structures and dynamics of the universe and allows study of f ...
. STScI hosts an annual scientific symposium held each spring as well as several smaller scientific workshops. The employment of an active scientific staff at STScI helps to ensure that HST, and eventually JWST, perform at peak capability.


Public outreach

STScI's Office of Public Outreach (OPO) provides a wide array of products and services designed to share and communicate the science and discoveries of HST, JWST, Roman, and astronomy in general with the general public. OPO's efforts focus on meeting the needs of the media, the informal science education community, and the general public. OPO produces approximately 40 new press releases each year featuring HST discoveries and science results. These media packages include news stories, Hubble images, explanatory artwork, animations, and supplementary information for use by print, broadcast, and online media. OPO also participates in press conferences for particularly newsworthy discoveries, and conducts science writers' workshops for in-depth sessions with scientists working on current astrophysical research problems. In addition to news releases, OPO develops a variety of astronomy-related products and features for use by the general public and informal education venues including museums, science centers, planetariums, and libraries. These include background articles, telescope imagery, illustrations, diagrams, infographics, videos, scientific visualizations, virtual reality, and interactives. Most of these resources are distributed via websites developed and managed by STScI, includin
HubblesiteWebbtelescopeViewSpace
an
Illuminated Universe
Content is also distributed via social media platforms, including Facebook, Twitter, Instagram, and YouTube. OPO also conducts outreach via live events in person and online. These include a regular Public Lecture Series as well as attendance at various local and national STEM events. OPO also provides support to informal education venues in the form of print materials, program/event resources, and professional development. OPO's outreach efforts are conducted in partnership with the Hubble, Webb, and Roman mission offices and with other institutions unde
NASA's Universe of Learning


References


External links

* {{Authority control Hubble Space Telescope
Space Telescope A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Suggested by Lyman Spitzer in 1946, the first operational telescopes were the American Orbiting Astronomical Observatory, OAO-2 launched ...
James Webb Space Telescope