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In 1911 it was revealed that Curie was involved in a year-long affair with physicist Paul Langevin, a former student of Pierre Curie's, a married man who was estranged from his wife. This resulted in a press scandal that was exploited by her academic opponents. Curie (then in her mid-40s) was five years older than Langevin and was misrepresented in the tabloids as a foreign Jewish home-wrecker. When the scandal broke, she was away at a conference in Belgium; on her return, she found an angry mob in front of her house and had to seek refuge, with her daughters, in the home of her friend, Camille Marbo.
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International recognition for her work had been growing to new heights, and the Royal Swedish Academy of Sciences, overcoming opposition prompted by the Langevin scandal, honoured her a second time, with the 1911 Nobel Prize in Chemistry. This award was "in recognition of her services to the advancement of chemistry by the discovery of the elements radium and polonium, by the isolation of radium and the study of the nature and compounds of this remarkable element." Because of the negative publicity due to her affair with Langevin, the chair of the Nobel committee, Svante Arrhenius, attempted to prevent her attendance at the official ceremony for her Nobel Prize in Chemistry, citing her questionable moral standing. Curie replied that she would be present at the ceremony, because "the prize has been given to her for her discovery of polonium and radium" and that "there is no relation between her scientific work and the facts of her private life".
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She was the first person to win or share two Nobel Prizes, and remains alone with Linus Pauling as Nobel laureates in two fields each. A delegation of celebrated Polish men of learning, headed by novelist Henryk Sienkiewicz, encouraged her to return to Poland and continue her research in her native country. Curie's second Nobel Prize enabled her to persuade the French government to support the Radium Institute, built in 1914, where research was conducted in chemistry, physics, and medicine. A month after accepting her 1911 Nobel Prize, she was hospitalised with depression and a kidney ailment. For most of 1912, she avoided public life but did spend time in England with her friend and fellow physicist, Hertha Ayrton. She returned to her laboratory only in December, after a break of about 14 months.
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In 1912 the Warsaw Scientific Society offered her the directorship of a new laboratory in Warsaw but she declined, focusing on the developing Radium Institute to be completed in August 1914, and on a new street named Rue Pierre-Curie. She was appointed Director of the Curie Laboratory in the Radium Institute of the University of Paris, founded in 1914. She visited Poland in 1913 and was welcomed in Warsaw but the visit was mostly ignored by the Russian authorities. The institute's development was interrupted by the coming war, as most researchers were drafted into the French Army, and it fully resumed its activities in 1919.
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During World War I, Curie recognised that wounded soldiers were best served if operated upon as soon as possible. She saw a need for field radiological centres near the front lines to assist battlefield surgeons, including to obviate amputations when in fact limbs could be saved. After a quick study of radiology, anatomy, and automotive mechanics she procured X-ray equipment, vehicles, auxiliary generators, and developed mobile radiography units, which came to be popularly known as "petites Curies" ("Little Curies"). She became the director of the Red Cross Radiology Service and set up France's first military radiology centre, operational by late 1914. Assisted at first by a military doctor and her 17-year-old daughter Irène, Curie directed the installation of 20 mobile radiological vehicles and another 200 radiological units at field hospitals in the first year of the war. Later, she began training other women as aides.
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In 1915, Curie produced hollow needles containing "radium emanation", a colourless, radioactive gas given off by radium, later identified as radon, to be used for sterilizing infected tissue. She provided the radium from her own one-gram supply. It is estimated that over a million wounded soldiers were treated with her X-ray units. Busy with this work, she carried out very little scientific research during that period. In spite of all her humanitarian contributions to the French war effort, Curie never received any formal recognition of it from the French government.
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Also, promptly after the war started, she attempted to donate her gold Nobel Prize medals to the war effort but the French National Bank refused to accept them. She did buy war bonds, using her Nobel Prize money. She said:She was also an active member in committees of Polonia in France dedicated to the Polish cause. After the war, she summarized her wartime experiences in a book, "Radiology in War" (1919).
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In 1920, for the 25th anniversary of the discovery of radium, the French government established a stipend for her; its previous recipient was Louis Pasteur (1822–95). In 1921, she was welcomed triumphantly when she toured the United States to raise funds for research on radium. Mrs. William Brown Meloney, after interviewing Curie, created a "Marie Curie Radium Fund" and raised money to buy radium, publicising her trip.
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In 1921, U.S. President Warren G. Harding received her at the White House to present her with the 1 gram of radium collected in the United States, and the First Lady praised her as an example of a professional achiever who was also a supportive wife. Before the meeting, recognising her growing fame abroad, and embarrassed by the fact that she had no French official distinctions to wear in public, the French government offered her a Legion of Honour award, but she refused. In 1922 she became a fellow of the French Academy of Medicine. She also travelled to other countries, appearing publicly and giving lectures in Belgium, Brazil, Spain, and Czechoslovakia.
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Led by Curie, the Institute produced four more Nobel Prize winners, including her daughter Irène Joliot-Curie and her son-in-law, Frédéric Joliot-Curie. Eventually it became one of the world's four major radioactivity-research laboratories, the others being the Cavendish Laboratory, with Ernest Rutherford; the Institute for Radium Research, Vienna, with Stefan Meyer; and the Kaiser Wilhelm Institute for Chemistry, with Otto Hahn and Lise Meitner.
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In August 1922 Marie Curie became a member of the League of Nations' newly created International Committee on Intellectual Cooperation. She sat on the committee until 1934 and contributed to League of Nations' scientific coordination with other prominent researchers such as Albert Einstein, Hendrik Lorentz, and Henri Bergson. In 1923 she wrote a biography of her late husband, titled "Pierre Curie". In 1925 she visited Poland to participate in a ceremony laying the foundations for Warsaw's Radium Institute. Her second American tour, in 1929, succeeded in equipping the Warsaw Radium Institute with radium; the Institute opened in 1932, with her sister Bronisława its director. These distractions from her scientific labours, and the attendant publicity, caused her much discomfort but provided resources for her work. In 1930 she was elected to the International Atomic Weights Committee, on which she served until her death. In 1931, Curie was awarded the Cameron Prize for Therapeutics of the University of Edinburgh.
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Curie visited Poland for the last time in early 1934. A few months later, on 4 July 1934, she died aged 66 at the Sancellemoz sanatorium in Passy, Haute-Savoie, from aplastic anemia believed to have been contracted from her long-term exposure to radiation, causing damage to her bone marrow.
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The damaging effects of ionising radiation were not known at the time of her work, which had been carried out without the safety measures later developed. She had carried test tubes containing radioactive isotopes in her pocket, and she stored them in her desk drawer, remarking on the faint light that the substances gave off in the dark. Curie was also exposed to X-rays from unshielded equipment while serving as a radiologist in field hospitals during the war. In fact, when Curie's body was exhumed in 1995, the French "Office de Protection contre les Rayonnements Ionisants" ("ORPI") "concluded that she could not have been exposed to lethal levels of radium while she was alive". They pointed out that radium poses a risk only if it is ingested, and speculated that her illness was more likely to have been due to her use of radiography during the First World War.
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She was interred at the cemetery in Sceaux, alongside her husband Pierre. Sixty years later, in 1995, in honour of their achievements, the remains of both were transferred to the Paris Panthéon. Their remains were sealed in a lead lining because of the radioactivity. She became the second woman to be interred at the Panthéon (after Sophie Berthelot) and the first woman to be honoured with interment in the Panthéon on her own merits.
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Because of their levels of radioactive contamination, her papers from the 1890s are considered too dangerous to handle. Even her cookbooks are highly radioactive. Her papers are kept in lead-lined boxes, and those who wish to consult them must wear protective clothing. In her last year, she worked on a book, "Radioactivity", which was published posthumously in 1935.
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The physical and societal aspects of the Curies' work contributed to shaping the world of the twentieth and twenty-first centuries. Cornell University professor Williams observes:
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If Curie's work helped overturn established ideas in physics and chemistry, it has had an equally profound effect in the societal sphere. To attain her scientific achievements, she had to overcome barriers, in both her native and her adoptive country, that were placed in her way because she was a woman. This aspect of her life and career is highlighted in Françoise Giroud's "Marie Curie: A Life", which emphasizes Curie's role as a feminist precursor.
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She was known for her honesty and moderate lifestyle. Having received a small scholarship in 1893, she returned it in 1897 as soon as she began earning her keep. She gave much of her first Nobel Prize money to friends, family, students, and research associates. In an unusual decision, Curie intentionally refrained from patenting the radium-isolation process so that the scientific community could do research unhindered. She insisted that monetary gifts and awards be given to the scientific institutions she was affiliated with rather than to her. She and her husband often refused awards and medals. Albert Einstein reportedly remarked that she was probably the only person who could not be corrupted by fame.
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As one of the most famous scientists, Marie Curie has become an icon in the scientific world and has received tributes from across the globe, even in the realm of pop culture.
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In a 2009 poll carried out by "New Scientist", she was voted the "most inspirational woman in science". Curie received 25.1 percent of all votes cast, nearly twice as many as second-place Rosalind Franklin (14.2 per cent).
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On the centenary of her second Nobel Prize, Poland declared 2011 the Year of Marie Curie; and the United Nations declared that this would be the International Year of Chemistry. An artistic installation celebrating "Madame Curie" filled the Jacobs Gallery at San Diego's Museum of Contemporary Art. On 7 November, Google celebrated the anniversary of her birth with a special Google Doodle. On 10 December, the New York Academy of Sciences celebrated the centenary of Marie Curie's second Nobel Prize in the presence of Princess Madeleine of Sweden.
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Marie Curie was the first woman to win a Nobel Prize, the first person to win two Nobel Prizes, the only woman to win in two fields, and the only person to win in multiple sciences. Awards that she received include:
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She received numerous honorary degrees from universities across the world. In Poland, she received honorary doctorates from the Lwów Polytechnic (1912), Poznań University (1922), Kraków's Jagiellonian University (1924), and the Warsaw Polytechnic (1926). In 1920 she became the first female member of The Royal Danish Academy of Sciences and Letters. In 1921, in the U.S., she was awarded membership in the Iota Sigma Pi women scientists' society. In 1924, she became an Honorary Member of the Polish Chemical Society. Marie Curie's 1898 publication with her husband and their collaborator Gustave Bémont of their discovery of radium and polonium was honoured by a Citation for Chemical Breakthrough Award from the Division of History of Chemistry of the American Chemical Society presented to the ESPCI Paris in 2015.
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Several institutions presently bear her name, including the two Curie institutes which she founded: the Maria Sklodowska-Curie National Research Institute of Oncology in Warsaw, and the "Institut Curie" in Paris. The Maria Curie-Skłodowska University, in Lublin, was founded in 1944; and the Pierre and Marie Curie University (also known as Paris VI) was France's pre-eminent science university, which would later merge to form the Sorbonne University. In Britain, the Marie Curie charity was organized in 1948 to care for the terminally ill.
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Two museums are devoted to Marie Curie. In 1967, the Maria Skłodowska-Curie Museum was established in Warsaw's "New Town", at her birthplace on "ulica Freta" (Freta Street). Her Paris laboratory is preserved as the Musée Curie, open since 1992.
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Curie's likeness has appeared on banknotes, stamps and coins around the world. She was featured on the Polish late-1980s 20,000-"złoty" banknote as well as on the last French 500-franc note, before the franc was replaced by the euro. Curie-themed postage stamps from Mali, the Republic of Togo, Zambia, and the Republic of Guinea actually show a picture of Susan Marie Frontczak portraying Curie in a 2001 picture by Paul Schroeder.
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Her likeness or name has appeared on several artistic works. In 1935, Michalina Mościcka, wife of Polish President Ignacy Mościcki, unveiled a statue of Marie Curie before Warsaw's Radium Institute; during the 1944 Second World War Warsaw Uprising against the Nazi German occupation, the monument was damaged by gunfire; after the war it was decided to leave the bullet marks on the statue and its pedestal. Her name is included on the "Monument to the X-ray and Radium Martyrs of All Nations", erected in Hamburg, Germany in 1936. In 1955 Jozef Mazur created a stained glass panel of her, the Maria Skłodowska-Curie Medallion, featured in the University at Buffalo Polish Room. In 2011, on the centenary of Marie Curie's second Nobel Prize, an allegorical mural was painted on the façade of her Warsaw birthplace. It depicted an infant Maria Skłodowska holding a test tube from which emanated the elements that she would discover as an adult: polonium and radium.
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Curie is the subject of the 2013 play, "False Assumptions", by Lawrence Aronovitch, in which the ghosts of three other women scientists observe events in her life. Curie has also been portrayed by Susan Marie Frontczak in her play, "Manya: The Living History of Marie Curie", a one-woman show which by 2014 had been performed in 30 U.S. states and nine countries.
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The James Webb Space Telescope (JWST) is a space telescope which conducts infrared astronomy. As the largest optical telescope in space, its high resolution and sensitivity allow it to view objects too old, distant, or faint for the Hubble Space Telescope. This will enable investigations across many fields of astronomy and cosmology, such as observation of the first stars, the formation of the first galaxies, and detailed atmospheric characterization of potentially habitable exoplanets.
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The U.S. National Aeronautics and Space Administration (NASA) led JWST's design and development and partnered with two main agencies: the European Space Agency (ESA) and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center (GSFC) in Maryland managed telescope development, the Space Telescope Science Institute in Baltimore on the Homewood Campus of Johns Hopkins University operates JWST, and the prime contractor was Northrop Grumman. The telescope is named after James E. Webb, who was the administrator of NASA from 1961 to 1968 during the Mercury, Gemini, and Apollo programs.
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The James Webb Space Telescope was launched on 25 December 2021 on an Ariane 5 rocket from Kourou, French Guiana, and arrived at the Sun–Earth L Lagrange point in January 2022. The first JWST image was released to the public via a press conference on 11 July 2022.
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JWST's primary mirror consists of 18 hexagonal mirror segments made of gold-plated beryllium, which combined create a mirror, compared with Hubble's . This gives JWST a light-collecting area of about 25 square meters, about six times that of Hubble. Unlike Hubble, which observes in the near ultraviolet and visible (0.1 to 0.8 μm), and near infrared (0.8–2.5 μm) spectra, JWST observes in a lower frequency range, from long-wavelength visible light (red) through mid-infrared (0.6–28.3 μm). The telescope must be kept extremely cold, below , such that the infrared light emitted by the telescope itself does not interfere with the collected light. It is deployed in a solar orbit near the Sun–Earth L Lagrange point, about from Earth, where its five-layer sunshield protects it from warming by the Sun, Earth, and Moon.
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Initial designs for the telescope, then named the Next Generation Space Telescope, began in 1996. Two concept studies were commissioned in 1999, for a potential launch in 2007 and a US$1 billion budget. The program was plagued with enormous cost overruns and delays; a major redesign in 2005 led to the current approach, with construction completed in 2016 at a total cost of US$10 billion. The high-stakes nature of the launch and the telescope's complexity were remarked upon by the media, scientists, and engineers.
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The James Webb Space Telescope has a mass that is about half of Hubble Space Telescope's mass. The JWST has a -diameter gold-coated beryllium primary mirror made up of 18 separate hexagonal mirrors. The mirror has a polished area of , of which is obscured by the secondary support struts, giving a total collecting area of . This is over six times larger than the collecting area of Hubble's diameter mirror, which has a collecting area of . The mirror has a gold coating to provide infrared reflectivity and this is covered by a thin layer of glass for durability.
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JWST is designed primarily for near-infrared astronomy, but can also see orange and red visible light, as well as the mid-infrared region, depending on the instrument. It can detect objects up to 100 times fainter than Hubble can, and objects much earlier in the history of the universe, back to redshift z≈20 (about 180 million years cosmic time after the Big Bang). For comparison, the earliest stars are thought to have formed between z≈30 and z≈20 (100–180 million years cosmic time), and the first galaxies may have formed around redshift z≈15 (about 270 million years cosmic time). Hubble is unable to see further back than very early reionization at about z≈11.1 (galaxy GN-z11, 400 million years cosmic time).
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Ground-based telescopes must look through Earth's atmosphere, which is opaque in many infrared bands (see figure at right). Even where the atmosphere is transparent, many of the target chemical compounds, such as water, carbon dioxide, and methane, also exist in the Earth's atmosphere, vastly complicating analysis. Existing space telescopes such as Hubble cannot study these bands since their mirrors are insufficiently cool (the Hubble mirror is maintained at about ) which means that the telescope itself radiates strongly in the relevant infrared bands.
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JWST can also observe objects in the Solar System at an angle of more than 85° from the Sun and having an apparent angular rate of motion less than 0.03 arc seconds per second. This includes Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, their satellites, and comets, asteroids and minor planets at or beyond the orbit of Mars. JWST has the near-IR and mid-IR sensitivity to be able to observe virtually all known Kuiper Belt Objects. In addition, it can observe opportunistic and unplanned targets within 48 hours of a decision to do so, such as supernovae and gamma ray bursts.
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JWST operates in a halo orbit, circling around a point in space known as the Sun–Earth L Lagrange point, approximately beyond Earth's orbit around the Sun. Its actual position varies between about from L as it orbits, keeping it out of both Earth and Moon's shadow. By way of comparison, Hubble orbits above Earth's surface, and the Moon is roughly from Earth. Objects near this Sun–Earth point can orbit the Sun in synchrony with the Earth, allowing the telescope to remain at a roughly constant distance with continuous orientation of its sunshield and equipment bus toward the Sun, Earth and Moon. Combined with its wide shadow-avoiding orbit, the telescope can simultaneously block incoming heat and light from all three of these bodies and avoid even the smallest changes of temperature from Earth and Moon shadows that would affect the structure, yet still maintain uninterrupted solar power and Earth communications on its sun-facing side. This arrangement keeps the temperature of the spacecraft constant and below the necessary for faint infrared observations.
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To make observations in the infrared spectrum, JWST must be kept under ; otherwise, infrared radiation from the telescope itself would overwhelm its instruments. Its large sunshield blocks light and heat from the Sun, Earth, and Moon, and its position near the Sun–Earth keeps all three bodies on the same side of the spacecraft at all times. Its halo orbit around the L point avoids the shadow of the Earth and Moon, maintaining a constant environment for the sunshield and solar arrays. The resulting stable temperature for the structures on the dark side is critical to maintaining precise alignment of the primary mirror segments.
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The five-layer sunshield, each layer as thin as a human hair, is made of Kapton E film, coated with aluminum on both sides and a layer of doped silicon on the Sun-facing side of the two hottest layers to reflect the Sun's heat back into space. Accidental tears of the delicate film structure during deployment testing in 2018 led to further delays to the telescope.
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The sunshield was designed to be folded twelve times (concertina style) so that it would fit within the Ariane 5 rocket's payload fairing, which is in diameter, and long. The shield's fully deployed dimensions were planned as .
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Keeping within the shadow of the sunshield limits the field of regard of JWST at any given time. The telescope can see 40 percent of the sky from any one position, but can see all of the sky over a period of six months.
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JWST's primary mirror is a -diameter gold-coated beryllium reflector with a collecting area of . If it had been designed as a single large mirror, it would have been too large for existing launch vehicles. The mirror is therefore composed of 18 hexagonal segments (a technique pioneered by Guido Horn d'Arturo), which unfolded after the telescope was launched. Image plane wavefront sensing through phase retrieval is used to position the mirror segments in the correct location using very precise micro-motors. Subsequent to this initial configuration, they only need occasional updates every few days to retain optimal focus. This is unlike terrestrial telescopes, for example the Keck telescopes, which continually adjust their mirror segments using active optics to overcome the effects of gravitational and wind loading. The Webb telescope uses 132 small motors (called actuators) to position and occasionally adjust the optics. The actuators can position the mirror with 10 nanometer accuracy.
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JWST's optical design is a three-mirror anastigmat, which makes use of curved secondary and tertiary mirrors to deliver images that are free from optical aberrations over a wide field. The secondary mirror is in diameter. In addition, there is a fine steering mirror which can adjust its position many times per second to provide image stabilization. Photographs taken by the JWST have six spikes plus two fainter ones due to the spider supporting the secondary mirror.
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The Integrated Science Instrument Module (ISIM) is a framework that provides electrical power, computing resources, cooling capability as well as structural stability to the Webb telescope. It is made with bonded graphite-epoxy composite attached to the underside of Webb's telescope structure. The ISIM holds the four science instruments and a guide camera.
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NIRCam and MIRI feature starlight-blocking coronagraphs for observation of faint targets such as extrasolar planets and circumstellar disks very close to bright stars.
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The spacecraft bus is the primary support component of the James Webb Space Telescope, hosting a multitude of computing, communication, electric power, propulsion, and structural parts. Along with the sunshield, it forms the spacecraft element of the space telescope. The spacecraft bus is on the Sun-facing "warm" side of the sunshield and operates at a temperature of about .
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The structure of the spacecraft bus has a mass of , and must support the space telescope. It is made primarily of graphite composite material. It was assembled in California, assembly was completed in 2015, and then it had to be integrated with the rest of the space telescope leading up to its 2021 launch. The spacecraft bus can rotate the telescope with a pointing precision of one arcsecond, and isolates vibration down to two milliarcseconds.
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Webb has two pairs of rocket engines (one pair for redundancy) to make course corrections on the way to L and for station keepingmaintaining the correct position in the halo orbit. Eight smaller thrusters are used for attitude controlthe correct pointing of the spacecraft. The engines use hydrazine fuel ( at launch) and dinitrogen tetroxide as oxidizer ( at launch).
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JWST is not intended to be serviced in space. A crewed mission to repair or upgrade the observatory, as was done for Hubble, would not currently be possible, and according to NASA Associate Administrator Thomas Zurbuchen, despite best efforts, an uncrewed remote mission was found to be beyond current technology at the time JWST was designed. During the long JWST testing period, NASA officials referred to the idea of a servicing mission, but no plans were announced. Since the successful launch, NASA has stated that nevertheless limited accommodation was made to facilitate future servicing missions. These accommodations included precise guidance markers in the form of crosses on the surface of JWST, for use by remote servicing missions, as well as refillable fuel tanks, removable heat protectors, and accessible attachment points.
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Ilana Dashevsky and Vicki Balzano write that JWST uses modified version of JavaScript, called Nombas ScriptEase 5.00e, for its operations; it follows the ECMAScript standard and "allows for a modular design flow, where on-board scripts call lower-level scripts that are defined as functions". "The JWST science operations will be driven by ASCII (instead of binary command blocks) on-board scripts, written in a customized version of JavaScript. The script interpreter is run by the flight software, which is written in C++. The flight software operates the spacecraft and the science instruments."
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The desire for a large infrared space telescope traces back decades. In the United States, the Space Infrared Telescope Facility (later called the Spitzer Space Telescope) was planned while the Space Shuttle was in development, and the potential for infrared astronomy was acknowledged at that time. Unlike ground telescopes, space observatories were free from atmospheric absorption of infrared light. Space observatories opened up a whole "new sky" for astronomers.
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However, infrared telescopes have a disadvantage: they need to stay extremely cold, and the longer the wavelength of infrared, the colder they need to be. If not, the background heat of the device itself overwhelms the detectors, making it effectively blind. This can be overcome by careful spacecraft design, in particular by placing the telescope in a dewar with an extremely cold substance, such as liquid helium. The coolant will slowly vaporize, limiting the lifetime of the instrument from as short as a few months to a few years at most.
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In some cases, it is possible to maintain a temperature low enough through the design of the spacecraft to enable near-infrared observations without a supply of coolant, such as the extended missions of Spitzer Space Telescope and Wide-field Infrared Survey Explorer, which operated at reduced capacity after coolant depletion. Another example is Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) instrument, which started out using a block of nitrogen ice that depleted after a couple of years, but was then replaced during the STS-109 servicing mission with a cryocooler that worked continuously. The James Webb Space Telescope is designed to cool itself without a dewar, using a combination of sunshields and radiators, with the mid-infrared instrument using an additional cryocooler.
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JWST's delays and cost increases have been compared to those of its predecessor, the Hubble Space Telescope. When Hubble formally started in 1972, it had an estimated development cost of US$300 million (or about US$1 billion in 2006 constant dollars), but by the time it was sent into orbit in 1990, the cost was about four times that. In addition, new instruments and servicing missions increased the cost to at least US$9 billion by 2006.
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Discussions of a Hubble follow-on started in the 1980s, but serious planning began in the early 1990s. The "Hi-Z" telescope concept was developed between 1989 and 1994: a fully baffled aperture infrared telescope that would recede to an orbit at 3 Astronomical unit (AU). This distant orbit would have benefited from reduced light noise from zodiacal dust. Other early plans called for a NEXUS precursor telescope mission.
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Correcting the flawed optics of the Hubble Space Telescope in its first years played a significant role in the birth of the JWST. In 1993, NASA conducted STS-61, the Space Shuttle mission that replaced HST's camera and a installed a retrofit for its imaging spectrograph to compensate for the spherical aberration in its primary mirror.
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The HST & Beyond Committee was formed in 1994 "to study possible missions and programs for optical-ultraviolet astronomy in space for the first decades of the 21st century." Emboldened by HST's success, its 1996 report explored the concept of a larger and much colder, infrared-sensitive telescope that could reach back in cosmic time to the birth of the first galaxies. This high-priority science goal was beyond the HST's capability because, as a warm telescope, it is blinded by infrared emission from its own optical system. In addition to recommendations to extend the HST mission to 2005 and to develop technologies for finding planets around other stars, NASA embraced the chief recommendation of HST & Beyond for a large, cold space telescope (radiatively cooled far below 0 °C), and began the planning process for the future JWST.
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Preparation for the 2000 Astronomy and Astrophysics Decadal Survey (a literature review produced by the United States National Research Council that includes identifying research priorities and making recommendations for the upcoming decade) included further development of the scientific program for what became known as the Next Generation Space Telescope, and advancements in relevant technologies by NASA. As it matured, studying the birth of galaxies in the young universe, and searching for planets around other starsthe prime goals coalesced as "Origins" by HST & Beyond became prominent.
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An administrator of NASA, Dan Goldin, coined the phrase "faster, better, cheaper", and opted for the next big paradigm shift for astronomy, namely, breaking the barrier of a single mirror. That meant going from "eliminate moving parts" to "learn to live with moving parts" (i.e. segmented optics). With the goal to reduce mass density tenfold, silicon carbide with a very thin layer of glass on top was first looked at, but beryllium was selected at the end.
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The mid-1990s era of "faster, better, cheaper" produced the NGST concept, with an aperture to be flown to , roughly estimated to cost US$500 million. In 1997, NASA worked with the Goddard Space Flight Center, Ball Aerospace & Technologies, and TRW to conduct technical requirement and cost studies of the three different concepts, and in 1999 selected Lockheed Martin and TRW for preliminary concept studies. Launch was at that time planned for 2007, but the launch date was pushed back many times (see table further down).
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In 2002, the project was renamed after NASA's second administrator (1961–1968), James E. Webb (1906–1992). Webb led the agency during the Apollo program and established scientific research as a core NASA activity.
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In 2003, NASA awarded TRW the US$824.8 million prime contract for JWST. The design called for a de-scoped primary mirror and a launch date of 2010. Later that year, TRW was acquired by Northrop Grumman in a hostile bid and became Northrop Grumman Space Technology.
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Development was managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland, with John C. Mather as its project scientist. The primary contractor was Northrop Grumman Aerospace Systems, responsible for developing and building the spacecraft element, which included the satellite bus, sunshield, Deployable Tower Assembly (DTA) which connects the Optical Telescope Element to the spacecraft bus, and the Mid Boom Assembly (MBA) which helps to deploy the large sunshields on orbit, while Ball Aerospace & Technologies has been subcontracted to develop and build the OTE itself, and the Integrated Science Instrument Module (ISIM).
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Cost growth revealed in spring 2005 led to an August 2005 re-planning. The primary technical outcomes of the re-planning were significant changes in the integration and test plans, a 22-month launch delay (from 2011 to 2013), and elimination of system-level testing for observatory modes at wavelength shorter than 1.7 μm. Other major features of the observatory were unchanged. Following the re-planning, the project was independently reviewed in April 2006.
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In the 2005 re-plan, the life-cycle cost of the project was estimated at US$4.5 billion. This comprised approximately US$3.5 billion for design, development, launch and commissioning, and approximately US$1.0 billion for ten years of operations. The ESA agreed in 2004 to contributing about €300 million, including the launch. The Canadian Space Agency pledged CA$39 million in 2007 and in 2012 delivered its contributions in equipment to point the telescope and detect atmospheric conditions on distant planets.
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In January 2007, nine of the ten technology development items in the project successfully passed a Non-Advocate Review. These technologies were deemed sufficiently mature to retire significant risks in the project. The remaining technology development item (the MIRI cryocooler) completed its technology maturation milestone in April 2007. This technology review represented the beginning step in the process that ultimately moved the project into its detailed design phase (Phase C). By May 2007, costs were still on target. In March 2008, the project successfully completed its Preliminary Design Review (PDR). In April 2008, the project passed the Non-Advocate Review. Other passed reviews include the Integrated Science Instrument Module review in March 2009, the Optical Telescope Element review completed in October 2009, and the Sunshield review completed in January 2010.
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In April 2010, the telescope passed the technical portion of its Mission Critical Design Review (MCDR). Passing the MCDR signified the integrated observatory can meet all science and engineering requirements for its mission. The MCDR encompassed all previous design reviews. The project schedule underwent review during the months following the MCDR, in a process called the Independent Comprehensive Review Panel, which led to a re-plan of the mission aiming for a 2015 launch, but as late as 2018. By 2010, cost over-runs were impacting other projects, though JWST itself remained on schedule.
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Assembly of the hexagonal segments of the primary mirror, which was done via robotic arm, began in November 2015 and was completed on 3 February 2016. The secondary mirror was installed on 3 March 2016. Final construction of the Webb telescope was completed in November 2016, after which extensive testing procedures began.
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In March 2018, NASA delayed JWST's launch an additional 2 years to May 2020 after the telescope's sunshield ripped during a practice deployment and the sunshield's cables did not sufficiently tighten. In June 2018, NASA delayed the launch by an additional 10 months to March 2021, based on the assessment of the independent review board convened after the failed March 2018 test deployment. The review identified that JWST launch and deployment had 344 potential single-point failures – tasks that had no alternative or means of recovery if unsuccessful, and therefore had to succeed for the telescope to work. In August 2019, the mechanical integration of the telescope was completed, something that was scheduled to be done 12 years before in 2007.
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After construction was completed, JWST underwent final tests at a Northrop Grumman factory in Redondo Beach, California. A ship carrying the telescope left California on 26 September 2021, passed through the Panama Canal, and arrived in French Guiana on 12 October 2021.
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NASA's lifetime cost for the project is expected to be US$9.7 billion, of which US$8.8 billion was spent on spacecraft design and development and US$861 million is planned to support five years of mission operations. Representatives from ESA and CSA stated their project contributions amount to approximately €700 million and CA$200 million, respectively.
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A study in 1984 by the Space Science Board estimated that to build a next-generation infrared observatory in orbit would cost US$4 billion (US$7B in 2006 dollars, or $10B in 2020 dollars). While this came close to the final cost of JWST, the first NASA design considered in the late 1990s was more modest, aiming for a $1 billion price tag over 10 years of construction. Over time this design expanded, added funding for contingencies, and had scheduling delays.
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By 2008, when the project entered preliminary design review and was formally confirmed for construction, over US$1 billion had already been spent on developing the telescope, and the total budget was estimated at about US$5 billion (equivalent to $ billion in ). In summer 2010, the mission passed its Critical Design Review (CDR) with excellent grades on all technical matters, but schedule and cost slips at that time prompted Maryland U.S. Senator Barbara Mikulski to call for external review of the project. The Independent Comprehensive Review Panel (ICRP) chaired by J. Casani (JPL) found that the earliest possible launch date was in late 2015 at an extra cost of US$1.5 billion (for a total of US$6.5 billion). They also pointed out that this would have required extra funding in FY2011 and FY2012 and that any later launch date would lead to a higher total cost.
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On 6 July 2011, the United States House of Representatives' appropriations committee on Commerce, Justice, and Science moved to cancel the James Webb project by proposing an FY2012 budget that removed US$1.9 billion from NASA's overall budget, of which roughly one quarter was for JWST. US$3 billion had been spent and 75% of its hardware was in production. This budget proposal was approved by subcommittee vote the following day. The committee charged that the project was "billions of dollars over budget and plagued by poor management". In response, the American Astronomical Society issued a statement in support of JWST, as did Senator Mikulski. A number of editorials supporting JWST appeared in the international press during 2011 as well. In November 2011, Congress reversed plans to cancel JWST and instead capped additional funding to complete the project at US$8 billion.
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While similar issues had affected other major NASA projects such as the Hubble telescope, some scientists expressed concerns about growing costs and schedule delays for the Webb telescope, worrying that its budget might be competing with those of other space science programs. A 2010 "Nature" article described JWST as "the telescope that ate astronomy". NASA continued to defend the budget and timeline of the program to Congress.
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In 2018, Gregory L. Robinson was appointed as the new director of the Webb program. Robinson was credited with raising the program's schedule efficiency (how many measures were completed on time) from 50% to 95%. For his role in improving the performance of the Webb program, Robinsons's supervisor, Thomas Zurbuchen, called him "the most effective leader of a mission I have ever seen in the history of NASA." In July 2022, after Webb's commissioning process was complete and it began transmitting its first data, Robinson retired following a 33-year career at NASA.
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On 27 March 2018, NASA pushed back the launch to May 2020 or later, with a final cost estimate to come after a new launch window was determined with the European Space Agency (ESA). In 2019, its mission cost cap was increased by US$800 million. After launch windows were paused in 2020 due to the COVID-19 pandemic, JWST was finally launched at the end of 2021, with a total budget of just under US$10 billion.
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NASA, ESA and CSA have collaborated on the telescope since 1996. ESA's participation in construction and launch was approved by its members in 2003 and an agreement was signed between ESA and NASA in 2007. In exchange for full partnership, representation and access to the observatory for its astronomers, ESA is providing the NIRSpec instrument, the Optical Bench Assembly of the MIRI instrument, an Ariane 5 ECA launcher, and manpower to support operations. The CSA provided the Fine Guidance Sensor and the Near-Infrared Imager Slitless Spectrograph and manpower to support operations.
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Several thousand scientists, engineers, and technicians spanning 15 countries have contributed to the build, test and integration of the JWST. A total of 258 companies, government agencies, and academic institutions participated in the pre-launch project; 142 from the United States, 104 from 12 European countries (including 21 from the U.K., 16 from France, 12 from Germany and 7 international), and 12 from Canada. Other countries as NASA partners, such as Australia, were involved in post-launch operation.
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In 2002, NASA administrator (2001–2004) Sean O'Keefe made the decision to name the telescope after James E. Webb, the administrator of NASA from 1961 to 1968 during the Mercury, Gemini, and much of the Apollo programs.
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In 2015, concerns were raised around Webb's possible role in the lavender scare, the mid-20th-century persecution by the U.S. government targeting homosexuals in federal employment. In 2022, NASA released a report of an investigation and accompanying evidence, based on an examination of more than 50,000 documents. The report found there was no evidence of wrongdoing by Webb either in his time in the State Department or at NASA. As a result, NASA did not rename the telescope.
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These goals can be accomplished more effectively by observation in near-infrared light rather than light in the visible part of the spectrum. For this reason, JWST's instruments will not measure visible or ultraviolet light like the Hubble Telescope, but will have a much greater capacity to perform infrared astronomy. JWST will be sensitive to a range of wavelengths from 0.6 to 28 μm (corresponding respectively to orange light and deep infrared radiation at about ).
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JWST may be used to gather information on the dimming light of star KIC 8462852, which was discovered in 2015, and has some abnormal light-curve properties.
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Additionally, it will be able to tell if an exoplanet has methane in its atmosphere, allowing astronomers to determine whether or not the methane is a biosignature.
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JWST orbits the Sun near the second Lagrange point () of the Sun–Earth system, which is farther from the Sun than the Earth's orbit, and about four times farther than the Moon's orbit. Normally an object circling the Sun farther out than Earth would take longer than one year to complete its orbit. But near the point, the combined gravitational pull of the Earth and the Sun allow a spacecraft to orbit the Sun in the same time that it takes the Earth. Staying close to Earth allows data rates to be much faster for a given size of antenna.
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The telescope circles about the Sun–Earth point in a halo orbit, which is inclined with respect to the ecliptic, has a radius varying between about and , and takes about half a year to complete. Since is just an equilibrium point with no gravitational pull, a halo orbit is not an orbit in the usual sense: the spacecraft is actually in orbit around the Sun, and the halo orbit can be thought of as controlled drifting to remain in the vicinity of the point. This requires some station-keeping: around per year from the total ∆"v" budget of . Two sets of thrusters constitute the observatory's propulsion system. Because the thrusters are located solely on the Sun-facing side of the observatory, all station-keeping operations are designed to slightly undershoot the required amount of thrust in order to avoid pushing the JWST beyond the semi-stable point, a situation which would be unrecoverable. Randy Kimble, the Integration and Test Project Scientist for the James Webb Space Telescope, compared the precise station-keeping of the JWST to "Sisyphus [...] rolling this rock up the gentle slope near the top of the hill – we never want it to roll over the crest and get away from him".
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JWST is the formal successor to the Hubble Space Telescope (HST), and since its primary emphasis is on infrared astronomy, it is also a successor to the Spitzer Space Telescope. JWST will far surpass both those telescopes, being able to see many more and much older stars and galaxies. Observing in the infrared spectrum is a key technique for achieving this, because of cosmological redshift, and because it better penetrates obscuring dust and gas. This allows observation of dimmer, cooler objects. Since water vapor and carbon dioxide in the Earth's atmosphere strongly absorbs most infrared, ground-based infrared astronomy is limited to narrow wavelength ranges where the atmosphere absorbs less strongly. Additionally, the atmosphere itself radiates in the infrared spectrum, often overwhelming light from the object being observed. This makes a space telescope preferable for infrared observation.
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The more distant an object is, the younger it appears; its light has taken longer to reach human observers. Because the universe is expanding, as the light travels it becomes red-shifted, and objects at extreme distances are therefore easier to see if viewed in the infrared. JWST's infrared capabilities are expected to let it see back in time to the first galaxies forming just a few hundred million years after the Big Bang.
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Infrared radiation can pass more freely through regions of cosmic dust that scatter visible light. Observations in infrared allow the study of objects and regions of space which would be obscured by gas and dust in the visible spectrum, such as the molecular clouds where stars are born, the circumstellar disks that give rise to planets, and the cores of active galaxies.
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Relatively cool objects (temperatures less than several thousand degrees) emit their radiation primarily in the infrared, as described by Planck's law. As a result, most objects that are cooler than stars are better studied in the infrared. This includes the clouds of the interstellar medium, brown dwarfs, planets both in our own and other solar systems, comets, and Kuiper belt objects that will be observed with the Mid-Infrared Instrument (MIRI).
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Some of the missions in infrared astronomy that impacted JWST development were Spitzer and the Wilkinson Microwave Anisotropy Probe (WMAP). Spitzer showed the importance of mid-infrared, which is helpful for tasks such as observing dust disks around stars. Also, the WMAP probe showed the universe was "lit up" at redshift 17, further underscoring the importance of the mid-infrared. Both these missions were launched in the early 2000s, in time to influence JWST development.
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The Space Telescope Science Institute (STScI), in Baltimore, Maryland, on the Homewood Campus of Johns Hopkins University, was selected in 2003 as the Science and Operations Center (S&OC) for JWST with an initial budget of US$162.2 million intended to support operations through the first year after launch. In this capacity, STScI was to be responsible for the scientific operation of the telescope and delivery of data products to the astronomical community. Data was to be transmitted from JWST to the ground via the NASA Deep Space Network, processed and calibrated at STScI, and then distributed online to astronomers worldwide. Similar to how Hubble is operated, anyone, anywhere in the world, will be allowed to submit proposals for observations. Each year several committees of astronomers will peer review the submitted proposals to select the projects to observe in the coming year. The authors of the chosen proposals will typically have one year of private access to the new observations, after which the data will become publicly available for download by anyone from the online archive at STScI.
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The bandwidth and digital throughput of the satellite is designed to operate at 458 gigabits of data per day for the length of the mission (equivalent to a sustained rate of 5.42 Mbps). Most of the data processing on the telescope is done by conventional single-board computers. The digitization of the analog data from the instruments is performed by the custom SIDECAR ASIC (System for Image Digitization, Enhancement, Control And Retrieval Application Specific Integrated Circuit). NASA stated that the SIDECAR ASIC will include all the functions of a instrument box in a package and consume only 11 milliwatts of power. Since this conversion must be done close to the detectors, on the cold side of the telescope, the low power dissipation is crucial for maintaining the low temperature required for optimal operation of JWST.
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The C3 mirror segment suffered a micrometeoroid strike from a large dust mote-sized particle between 23 and 25 May, the fifth and largest strike since launch, reported 8 June 2022, which required engineers to compensate for the strike using a mirror actuator. Despite the strike, a NASA characterization report states "all JWST observing modes have been reviewed and confirmed to be ready for science use" as of July 10, 2022.
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The launch (designated Ariane flight VA256) took place as scheduled at 12:20 UTC on 25 December 2021 on an Ariane 5 rocket that lifted off from the Guiana Space Centre in French Guiana. The telescope was confirmed to be receiving power, starting a two-week deployment phase of its parts and traveling to its target destination. The telescope was released from the upper stage 27 minutes 7 seconds after launch, beginning a 30-day adjustment to place the telescope in a Lissajous orbit around the Lagrange point.
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The telescope was launched with slightly less speed than needed to reach its final orbit, and slowed down as it travelled away from Earth, in order to reach L with only the velocity needed to enter its orbit there. The telescope reached L on 24 January 2022. The flight included three planned course corrections to adjust its speed and direction. This is because the observatory could recover from underthrust (going too slowly), but could not recover from overthrust (going too fast) – to protect highly temperature-sensitive instruments, the sunshield must remain between telescope and Sun, so the spacecraft could not turn around or use its thrusters to slow down.
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JWST was released from the rocket upper stage 27 minutes after a flawless launch. Starting 31 minutes after launch, and continuing for about 13 days, JWST began the process of deploying its solar array, antenna, sunshield, and mirrors. Nearly all deployment actions are commanded by the Space Telescope Science Institute in Baltimore, except for two early automatic steps, solar panel unfolding and communication antenna deployment. The mission was designed to give ground controllers flexibility to change or modify the deployment sequence in case of problems.
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At 7:50p.m. EST on 25 December 2021, about 12 hours after launch, the telescope's pair of primary rockets began firing for 65 minutes to make the first of three planned mid-course corrections. On day two, the high gain communication antenna deployed automatically.
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On 27 December 2021, at 60 hours after launch, Webb's rockets fired for nine minutes and 27 seconds to make the second of three mid-course corrections for the telescope to arrive at its L destination. On 28 December 2021, three days after launch, mission controllers began the multi-day deployment of Webb's all-important sunshield. On 30 December 2021, controllers successfully completed two more steps in unpacking the observatory. First, commands deployed the aft "momentum flap", a device that provides balance against solar pressure on the sunshield, saving fuel by reducing the need for thruster firing to maintain Webb's orientation.
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