James Webb Space Telescope

James Webb Space Telescope
James Webb Space Telescope

James Webb Space Telescope

The James Webb Space Telescope

is a space telescope designed primarily for conducting infrared astronomy. As the largest optical telescope in space, its greatly improved infrared resolution and sensitivity allow it to see objects too early, distant, or faint for the Hubble Space Telescope. Wikipedia
From NASA
The James Webb Space Telescope

Launch date: December 25, 2021


Cost: 10 billion USD (2016)
Rocket: Ariane 5 ECA (VA256)
Dimensions: 20.197 m × 14.162 m (66.26 ft × 46.46 ft), sun shield
Bandwidth: S-band up to 16 kbit/s; 40 kbit/s down S-band; Ka-band down to 28 Mbit/s
Operator: STScI (NASA) / ESA / CSA
Developer: Northrop Grumman; Ball Aerospace; L3Harris;
The James Webb Space Telescope
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The James Webb Space Telescope (JWST) is a space telescope designed primarily to perform infrared astronomy. As the largest optical telescope in space, its greatly improved infrared resolution and sensitivity allow it to see objects too early, distant, or faint for the Hubble Space Telescope. It is expected to enable a wide range of investigations in all areas of astronomy and cosmology, such as the observation of the first stars and the formation of the first galaxies, and the detailed atmospheric properties of potentially habitable exoplanets.

The James Webb Space Telescope
JWST spacecraft model 3.png
A rendering of the James Webb Space Telescope fully deployed.
Name
Next Generation Space Telescope (NGST; 1996–2002)
Type of mission
Astronomy
The operator
STScI (NASA)[1] / ESA / CSA
COMPARE ID
Edit this at 2021-130AWikidata.
SAT No
50463[2]
website
Official website
Mission duration
7 months, 2 days (elapsed)
5+1⁄2 years (primary mission)
10 years (planned)
20 years (life expectancy)
Characteristics of the spacecraft
Manufacturer
Northrop Grumman
Ball Aerospace
L3Harris[1]
Launch at scale.
6,161.4 kg (13,584 lb)
Dimensions
20.197 m × 14.162 m (66.26 ft × 46.46 ft), sun shield
power
2 kW
Start of the mission
issue date
December 25, 2021, 12:20 UTC
The rocket
Ariane 5 ECA (VA256)
Launch the site.
Center Special Giannis, ELA-3
The contractor
Arianespace
Entered service.
July 12, 2022
Orbital parameters
Reference system
Sun-Earth L2 orbit
Government
Halo orbit
Periapsis height
250,000 km (160,000 mi)
Apoapsis height
832,000 km (517,000 mi)[6]
Duration
6 months
Central telescope
Kind of
A telescope of course
Qatar
6.5 meters (21 feet)
Focal length
131.4 meters (431 feet)
Focal ratio
f/20.2
Collection area
25.4 m2 (273 sq ft)[7]
Wavelength
0.6–28.3 μm (orange to mid-infrared)
Transponders
Band
S-band, telemetry, and telecommand
Band of, Science Data Downlink
Bandwidth
S-band up: 16 kbit/s
S-band down: 40 kbit/s
Band down of up to 28 Mbit/s
Devices
FGS-NIRISSMIRINIRCamNIRSpec
Elements
Integrated Science Instrument Module Optical Telescope Element Spacecraft (Bus and Sunshield)
JWST Launch Logo.png
James Webb Space Telescope mission logo
The US National Aeronautics and Space Administration (NASA) led the development of JWST in collaboration with the European Space Agency (ESA) and the Canadian Space Agency (CSA). NASA Goddard Space Flight Center (GSFC) in Maryland managed the telescope’s development, the Space Telescope Science Institute in Baltimore at Johns Hopkins University’s Homewood campus operates JWST, and the prime contractor was Northrop Grumman. The telescope is named after James E. Webb, who was NASA administrator from 1961 to 1968 during the Mercury, Gemini, and Apollo programs.

The James Webb Space Telescope was launched on December 25, 2021, from Kourou, French Guiana, on an Ariane 5 rocket, and arrived at the Sun-Earth L2 Lagrange point in January 2022. The first image from JWST was released to the public through a press conference. On 11 July 2022. The telescope is the successor to Hubble as NASA’s flagship mission in astrophysics.

JWST’s primary mirror consists of 18 hexagonal mirror sections made of gold-plated beryllium, which together form a 6.5 m diameter (21 ft) mirror, compared to Hubble’s 2.4 m (7 ft 10 in). This gives JWST a light-gathering area of ​​about 25 square meters, about six times that of Hubble. Unlike Hubble, which observes in the near-ultraviolet, visible, and near-infrared (0.8–2.5 μm) [9] spectra, JWST observes from long-wavelength visible light (red) to mid-infrared (0.6–0.6 μm). Observes in the low-frequency range up to 28.3 μm). The telescope must be kept extremely cold, below 50 K (−223 °C; −370 °F), so that the infrared light emitted by the telescope does not interfere with the collected light. It is stationed in solar orbit near the Sun-Earth L2 Lagrange point, about 1.5 million kilometers (930,000 miles) from Earth, where its five-layer sunshield protects it from heat from the Sun, Earth, and Moon.

The initial design of the telescope

then named the Next Generation Space Telescope, began in 1996. Two concept studies were commissioned in 1999, for a possible launch in 2007 and a budget of US$1 billion. The program was plagued with high costs 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. Media, scientists on the lofty nature of the launch and the complexity of the telescope, And engineers commented.

Features


The James Webb Space Telescope has a mass that is half the mass of the Hubble Space Telescope. JWST has a 6.5-meter (21 ft)-diameter gold-coated beryllium primary mirror made up of 18 separate hexagonal mirrors. The mirror has a polished area of ​​26.3 m2 (283 sq ft), of which 0.9 m2 (9.7 sq ft) is obscured by secondary support struts, [10] giving a total collection area of ​​25.4 m2 (273 sq ft). Gives. This is six times larger than the collecting area of ​​Hubble’s 2.4 m (7.9 ft) diameter mirror, which has a collecting area of ​​4.0 m2 (43 sq ft). The mirror has a gold coating to provide infrared reflection and is covered with a thin layer of glass for durability.

JWST is primarily designed for near-infrared astronomy, but it can observe orange and red visible light as well as the mid-infrared region, depending on the instrument. It can detect 100 times more faint objects than Hubble, and objects much earlier in the history of the Universe, back to z≈20 (about 180 million years of cosmic time after the Big Bang).[12] For comparison, the oldest stars are thought to form between z≈30 and z≈20 (100–180 million years cosmic time), [13] and the first galaxies at redshift z≈15 (about 270 million years cosmic time) will be built around Time). Hubble is unable to look back further than the very early reionization[14][15] at about z≈11.1 (galactic GN-z11, 400 million years of cosmic time).

The design emphasizes the near-mid-infrared for several reasons:

High-redshift (very early and distant) objects shift their visible emission into the infrared, and therefore their light can only be observed today by infrared astronomy;
Infrared light passes through dust clouds more easily than visible light.
Cool objects such as debris disks and planets emit most strongly in the infrared.
These infrared bands are difficult to study from Earth or with existing space telescopes such as Hubble.

A rough plot of the absorption (or opacity) of the Earth’s atmosphere for various wavelengths of electromagnetic radiation, including visible light.
Ground-based telescopes must observe the Earth’s atmosphere, which is opaque in many infrared bands (see image at right). Even where the atmosphere is transparent, many target chemical compounds, such as water, carbon dioxide, and methane, are also present in Earth’s atmosphere, making analysis very complicated. Current space telescopes such as Hubble cannot study these bands because their mirrors are insufficiently cooled (Hubble’s mirror is maintained at about 15 °C [288 K; 59 °F]), which means that the telescope itself strongly diffuses in the relevant infrared bands.

JWST can also observe nearby objects, including objects in the Solar System, with apparent angular rates of motion of 0.030 arcseconds per second or less. This includes all planets and satellites outside Earth’s orbit, comets, and asteroids, and includes “virtually all” known Cooper Belt objects.[13] In addition, it is 48 hours after the decision to do so. Inside can observe opportunistic and unplanned targets, such as supernovae and gamma-ray bursts.

Top three-quarter view
Top three-quarter view

down (facing the sun)
down (facing the sun)

Location and Orbit

JWST operates in a halo orbit, orbiting a point in space called the Sun-Earth L2 Lagrange point, about 1,500,000 km (930,000 mi) from Earth’s orbit around the Sun. Its actual position varies between about 250,000 and 832,000 km (155,000–517,000 mi) from L2 as it orbits, keeping it out of the shadow of both Earth and the Moon. By comparison, Hubble orbits 550 km (340 mi) above Earth’s surface, and the Moon is about 400,000 km (250,000 mi) from Earth. Objects near this Sun-Earth L2 point can orbit the Sun in synchrony with the Earth, giving the telescope a nearly constant orientation to the Sun, Earth, and Moon with its unique sunshield and constant orientation of the instrument bus. Distance is allowed. Combined with its wide shadow-avoidance orbit, the telescope can simultaneously block the heat and light from all three bodies and avoid the small temperature changes from the Earth’s and Moon’s shadows that would affect the structure. affect, yet maintain uninterrupted solar energy and communication with the Earth on its sun-facing side. This arrangement keeps the spacecraft temperature constant and below the 50 K (−223 °C; −370 °F) necessary for faint infrared observations.

Sunshield protection


James Webb Space Telescope sun shield

A test unit of the SunShield was installed and deployed at Northrop Grumman’s facility in California, in 2014.
To make observations in the infrared spectrum, JWST must be present.
kept below 50 K (−223.2 °C; −369.7 °F); Otherwise, the infrared radiation from the telescope itself will overwhelm its instruments. It, therefore, uses a large sun shield to block light and heat from the Sun, Earth, and Moon, and its position near Sun-Earth L2 keeps all three bodies on the same side of the spacecraft at all times.[22 ] Its halo orbits around the L2 point, avoiding the shadow of the Earth and Moon, shielding the Sun and the Solar System
Maintains a constant environment for the array.[19] The shielding maintains a stable temperature for the dark side structure, which is important for maintaining the correct alignment of the mirror cores in space.

A five-layer sun shield, each layer as thin as a human hair,[23] is made of Kapton E, a polyimide film commercially available from DuPont, with a membrane specially coated with aluminum on both sides and sun-doped. There is a layer of silicone. The two hottest layers face reflecting the sun’s heat into space.[20] Accidental tears in the delicate film structure during deployment testing in 2018 caused further delays to the telescope.

The sunshield was designed to fold twelve times (concertina style) to fit inside the Ariane 5 rocket’s payload fairing, which is 4.57 m (15.0 ft) in diameter, and 16.19 m (53.1 ft) long. . The shield’s fully deployed dimensions were planned as 14.162 m × 21.197 m (46.46 ft × 69.54 ft). The Sunshield was assembled by hand at ManTech (NeXolve) in Huntsville, Alabama, before being shipped to Northrop Grumman in Redondo Beach, California for testing.

Being in the shadow of the sun shield limits the field relative to JWST at any given time. The telescope can see 40 percent of the sky from a single location but can see the entire sky over six months.

Optics

Main article: Optical telescope element

Engineers cleaning test mirrors from carbon dioxide ice, 2015.

Main mirror assembly attached to the front primary mirror, November 2016

The disparity is increased due to the color-coded mirror sections and spiders.
Images taken by JWST have six spikes plus two faint images due to the spider supporting the secondary mirror.

JWST’s primary mirror is a 6.5 m (21 ft)-diameter gold-coated beryllium reflector with a collecting area of ​​25.4 m2 (273 sq ft). If it were built as a large mirror, it would be too large for current launch vehicles. The mirror, therefore, consists of 18 hexagonal sections (a technique pioneered by Guido Horne d’Arturo), which emerged after the telescope was launched. Image plane wavefront sensing by phase recovery is used using highly precise micro-motors to precisely position the mirror segments. After this initial setting, they require only occasional updates every few days to maintain maximum focus.[28] This is in contrast to ground-based telescopes, for example, Keck telescopes, which rely on gravity and They continuously adjust their mirror sections using active optics to control the effects of wind loading.

Web telescopes use 132 small motors (called actuators) and occasionally adjust the optics as a telescope experiences certain environmental disturbances in space. Each of the 18 primary mirror segments is controlled by 6 positional actuators with a further ROC (radius of curvature) actuator in the center to adjust curvature (7 actuators per segment), for a total of 126 for the primary mirror actuators, and another 6 actuators for the secondary mirror, giving a total of 132.[31][32] The actuators can position the mirror with an accuracy of 10 nanometers (10 millionths of a millimeter).

The actuators are critical in maintaining the alignment of the telescope’s mirrors and are designed and manufactured by Ball Aerospace & Technologies. Each of the 132 actuators is driven by a single stepper motor, providing both fine and coarse adjustments. The actuators provide a coarse adjustment step size of 58 nanometers and a fine adjustment step size of 7 nanometers for larger adjustments.

JWST’s optical design is a three-mirror anastigmat, [36] which uses curved secondary and tertiary mirrors to provide images that are free of optical aberrations over a wide field of view. The diameter of the secondary mirror is 0.74 m (2.4 ft). In addition, there is an excellent steering mirror that can adjust its position several times per second to provide image stabilization.

Ball Aerospace & Technologies was the principal optical subcontractor for the JWST project, led by prime contractor Northrop Grumman Aerospace Systems, under a contract from NASA Goddard Space Flight Center in Greenbelt, Maryland.[37][38] ] In addition to mirrors, flight spares were polished by Ball Aerospace & Technologies on beryllium segment blanks produced by several companies, including Access, Brush Wellman, and Tinsley Laboratories.

Scientific instruments

NIRCam concluded in 2013.

Calibration Assembly, a company
Component of the NIRSpec instrument

MIRI
The Integrated Science Instrument Module (ISIM) is the framework that provides electrical power, computing resources, cooling capacity, as well as structural stability to the Webb Telescope. It is made with a graphite-epoxy compound bonded to the underside of the web’s telescopic structure. ISIM has four science instruments and a guide camera.[40]

The NIRCam (Near Infrared Camera) is an infrared imager with spectral coverage from the edge of the visible (0.6 μm) to the near-infrared (5 μm).[41][42] Each of the 4 megapixels There is 10 sensors. NIRCam serves as the observatory’s wavefront sensor, providing wavefront sensing and control activities that are used to align and focus the central parts of the mirror. NIRCam was built by a team led by the University of Arizona with principal investigator Marcia J. Rick. The industrial partner is Lockheed Martin’s Advanced Technology Center in Palo Alto, California.
NIRSpec (Near Infrared Spectrograph) performs spectroscopy at the same wavelength range. It was built by the European Space Agency at ESTEC in Noordwijk, the Netherlands. The lead development team includes members from Airbus Defense and Space, Ottobrunn and Friedrichshafen, Germany, and Goddard Space Flight Center. with Pierre Ferruit (École normale supérieure de Lyon) as NIRSpec project scientist. The NIRSpec design provides three observation modes: a low-resolution mode using a prism, an R~1000 multi-object mode, and an R~2700 integral field unit or long-slit spectroscopy mode. Switching of modes is done by operating a wavelength preselection mechanism called a filter wheel assembly and selecting the corresponding dispersive element (prism or grating) using a grating wheel assembly mechanism. Both mechanisms are based on the Infrared Space Observatory’s successful ISOPHOT wheel mechanism. Multi-object mode relies on a complex micro-shutter mechanism to allow simultaneous observation of hundreds of individual objects anywhere in the NIRSpec’s field of view. Each of the 4 megapixels has two sensors. The mechanisms and their optical elements were designed, integrated, and tested by Carl Zeiss Optronics GmbH (today Hensoldt) of Oberkochen, Germany under contract to Austria.
The MIRI (Mid-InfraRed Instrument) measures the mid-to-long infrared wavelength range between 5 and 27 μm.[45][46] It consists of both a mid-infrared camera and an imaging spectrometer.[37] MIRI was developed as a collaboration between NASA and a consortium of European countries and is led by George Rick (University of Arizona) and Gillian Wright (UK Astronomy Technology Centre, Edinburgh, Scotland, Science and Technology Facilities are part of the council). 43] MIRI features a wheel mechanism similar to NIRSpec, which was also developed and built by Carl Zeiss Optronics GmbH (today Henselt) under contract to the Max Planck Institute for Astronomy, Heidelberg, Germany. MIRI’s complete optical bench assembly was delivered to Goddard Space Flight Center in mid-2012 for final integration into ISIM. MIRI’s temperature should not exceed 6 K (−267 °C; −449 °F): a helium gas mechanical cooler on the hot side of the atmospheric shield provides this cooling.


FGS/NIRISS (Fine Guidance Sensor and Near-Infrared Imager and Slateless Spectrograph), led by the Canadian Space Agency under project scientist John Hutchings (Herzberg Astronomy and Astrophysics Research Centre, National Research Council), confirmed the vision. Used to do. of the observatory during science observations. Measurements from the FGS are used to control the spacecraft’s overall orientation and operate fine steering mirrors for image stabilization. The Canadian Space Agency is also providing the Near Infrared Imager and Slitless Spectrograph (NIRISS) module for astronomical imaging and spectroscopy in the 0.8 to 5 μm wavelength range, led by Principal Investigator René Doyon at the Université de Montréal. . Although they are often referred to together as a unit, NIRISS and FGS serve entirely different purposes, one being a scientific instrument and the other part of the observatory’s supporting infrastructure.
NIRCam and MIRI have starlight-blocking coronagraphs to observe faint targets such as exoplanets and circumstellar disks very close to bright stars.

Infrared detectors for the NIRCam, NIRSpec, FGS, and NIRISS modules were provided by Teledyne Imaging Sensors (formerly Rockwell Scientific Company). The James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) and the Command and Data Handling (ICDH) engineering team use SpaceWire to send data between science instruments and data handling equipment.

A spaceship bus

Main article: Spacecraft bus (James Webb Space Telescope)

Diagram of the spacecraft bus. The solar panel is green and the light purple panels are red.
gators
The spacecraft bus is the primary supporting component of the James Webb Space Telescope that hosts several computing, communications, electric power, propulsion, and structural components.[50] Along with the Sunshield, it is the spacecraft of the space telescope. [51] The other two major elements of JWST are the Integrated Science Instrument Module (ISIM) and the Optical Telescope Element (OTE). [52] ISIM Area 3 is also inside the spacecraft bus. Region 3 includes the ISIM command and data handling subsystem and the MIRI cryocooler.[52] The spacecraft bus is connected to the optical telescope element via a deployable tower assembly, which also connects to the sun shield.[50] The bus is on the sunward “hot” side of the sun shield and operates at a temperature of about 300 K (27 °C; 80 °F).

The spacecraft bus structure weighs 350 kg (770 lb) and must support the 6,200 kg (13,700 lb) space telescope.[53] It is made primarily of graphite composite material.[53] It is built in California. Assembled, Assembly 2015
It was completed, and then it was supposed to be integrated with the rest of the space telescope by early 2021. The spacecraft bus can rotate the telescope with a pointing accuracy of one arcsecond and can separate the vibrations by two milliseconds.

In central computing, memory storage, and communications equipment, processors and software directly transmit data to and from the equipment, solid-state memory cores, and radio systems that can transmit data back to Earth and receive commands. . [50] The computer also controls the spacecraft’s orientation, receives sensor data from the gyroscopes and Star Tracker, and sends commands to the reaction wheels or thrusters.

Webb has two pairs of rocket engines (one pair for redundancy) for course correction en route to L2 and for station keeping. Eight small thrusters are used for attitude control – precise pointing of the spacecraft.[55] The engines use hydrazine fuel (159 liters or 42 US gallons at launch) and dinitrogen tetroxide as an oxidizer. (79.5 liters or 21.0 US gallons at lunchtime).

Servicing

JWST is not intended to serve in space. A crewed mission to repair or upgrade the observatory, as was done for Hubble, would not currently be possible, [57] and according to NASA Associate Administrator Thomas Zerbuchen, despite best efforts, An uncrewed remote mission was found to be beyond current technology. At the time JWST was designed. During the extended JWST testing period, NASA officials referred to the idea of ​​a servicing mission, but no plans were announced.[59][60] Since the successful launch, NASA has stated that future servicing missions, if any, limited accommodations were made for convenience. These accommodations included cross-shaped precision guidance markers on the surface of the JWST, for use in remote servicing missions, as well as refillable fuel tanks, removable heat protectors, and accessible attachment points.

Comparison with other telescopes

Comparison with the Hubble Primary Mirror
Primary mirror size comparison between JWST and Hubble
The desire for a large infrared space telescope is decades old. In the United States, the Space Infrared Telescope Facility (SIRTF, later known as the Spitzer Space Telescope) was planned while the Space Shuttle was in development, and recognized the potential of infrared astronomy. [62] Unlike ground-based telescopes, space observatories were free of atmospheric absorption of infrared light. Space observatories opened up a whole “new sky” for astronomers.

Above 400 km nominal flight altitude, there is no measurable absorption in the weak atmosphere so detectors operating at all wavelengths from 5 μm to 1000 μm achieve high radiometric sensitivity.

— S. G. McCarthy and G. W. Autio, 1978
However, infrared telescopes have a disadvantage: they need to be extremely cool, and the longer the infrared wavelength, the cooler they need to be. If not, the background heat of the device itself overwhelms the detectors, effectively blinding them. This can be overcome by careful spacecraft design, particularly by encasing the telescope in a wall with a supercooling material, such as liquid helium. The coolant will slowly evaporate, limiting the life of the device from a few months to a few years at most.

In some cases, it is possible by spacecraft design to keep the temperature low enough to enable near-infrared observations without supplying coolant, such as the extended missions of the Spitzer Space Telescope and the Widefield Infrared Survey Explorer, which operate. At low capacity after coolant depletion. Another example is Hubble’s Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) instrument, which started using a block of nitrogen ice that ended up after one.
a few years, but was then replaced during the STS-109 servicing mission with a cryocooler that operated continuously. The James Webb Space Telescope is designed to be self-cooling without a shield, using a combination of sun shields and radiators, with the mid-infrared instrument using an additional cryocooler.

Selected space telescopes and instruments.
Name Launch Year Wavelength
(μm) Aperture
(m) cooling
Spacelab Infrared Telescope (IRT) 1985 1.7–118 0.15 Helium
Infrared Space Observatory (ISO)[65] 1995 2.5–240 0.60 Helium
Hubble Space Telescope Imaging Spectrograph (STIS) 1997 0.115–1.03 2.4 Passive
Hubble Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) 1997 0.8–2.4 2.4 Nitrogen, later cryocooler
Spitzer Space Telescope 2003 3–180 0.85 Helium
Hubble Wide Field Camera 3 (WFC3) 2009 0.2–1.7 2.4 Passive, and thermoelectric[66]
Herschel Space Observatory 2009 55–672 3.5 Helium
James Webb Space Telescope 2021 0.6–28.5 6.5 passive, and cryocooler (MIRI)
JWST’s delays and cost overruns are comparable to those of its predecessor, the Hubble Space Telescope. When Hubble was officially launched in 1972, its estimated development cost was US$300 million (or about US$1 billion in constant 2006 dollars), but by the time it was launched into orbit in 1990, the cost was nearly four times that. . In addition, new equipment and servicing missions increased costs to at least US$9 billion by 2006.

James Webb Space Telescope
James Webb Space Telescope

Part 2
NASA’s James Webb Space Telescope

The James Webb Space Telescope was launched on December 25, 2021.

It took the James Webb Space Telescope 30 days to travel nearly a million miles (1.5 million kilometers) to its permanent home: a Lagrange point — a gravitationally stable point in space. The telescope arrived at L2, the second Sun-Earth Lagrange point, on January 24, 2022. L2 is a place in space near the Earth that is opposite the Sun. This orbit will allow the telescope to stay in line with Earth as it orbits the Sun. It has been a popular location for several other space telescopes, including the Herschel Space Telescope and the Planck Space Observatory.
According to NASA (opens in new tab), the James Webb Space Telescope will focus on four main areas: the first light in the Universe, the accumulation of galaxies in the early Universe, stand-alone protoplanetary systems, and the birth of planets (including the origin of life.)

The James Webb Space Telescope will undergo a series of science and calibration tests including sunshield deployment, telescope deployment, instrument turning, and telescope alignment.

The James Webb Space Telescope will undergo a series of science and calibration tests including sunshield deployment, telescope deployment, instrument turning, and telescope alignment. (Image credit: Future)
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On July 11, NASA announced that all 17 observatory science instrument ‘modes’ had been fully tested and that the James Webb Space Telescope was ready to begin its epic science mission.

Like its predecessor, the Hubble Space Telescope, the powerful James Webb Space Telescope is expected to capture stunning images of celestial objects. Fortunately for astronomers, the Hubble Space Telescope is in good health and the two telescopes will likely work together during JWST’s first years. JWST will also observe exoplanets found by the Kepler space telescope, or follow up on real-time observations from ground-based space telescopes.

The James Webb Space Telescope is the product of an impressive international (opens in new tab) collaboration between NASA, the European Space Agency (ESA), and the Canadian Space Agency. According to NASA, JWST includes more than 300 universities, organizations, and companies in 29 US states and 14 countries. The nominal duration for the James Webb Space Telescope is five years, but the target is 10 years, according to ESA (opens in new tab).

Launch and deployment of the James Webb Space Telescope.
NASA’s James Webb Space Telescope (JWST) launched at 7:20 a.m. EST (1220 GMT; 9:20 a.m. local time in Kourou) on December 25, 2021, from ESA’s launch site in Kourou, French Guiana. Launched on Arianespace Ariane5. The rocket

Thanks to a successful and precise launch, NASA announced that JWST should have enough fuel to at least double its mission’s expected life of 10 years. Since its launch, the James Webb Space Telescope’s achievements have kept coming.

Where is the James Webb Space Telescope?
You can keep track of the web and what it’s the current pace of deployment with NASA’s Where’s It website (which which which which opens in a new tab).

An impressive HD video captured the observatory flying off the Ariane 5 rocket that carried it into space. The three-minute video shows Webb slowly pulling away from his rocket stage and turning on his solar panels.

After the James Webb Space Telescope separated from the Ariane 5 rocket that carried it into space. This is one of our last views of the impressive telescope.

After the James Webb Space Telescope separated from the Ariane 5 rocket that carried it into space. This is one of our last views of the impressive telescope. (Image credit: ESA)
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The James Webb Space Telescope deployed and tested a key antenna on Dec. 26, 2021, a process that took about an hour, according to a statement from NASA (opens in new tab). The antenna will be responsible for beaming science data back to Earth twice daily. Just one day later, on December 27, the observatory left lunar orbit.

On December 31, 2021, Webb successfully hoisted his giant sunshield. Tensioning of the five layers of the Sun Shield began on January 3, 2022, and was completed the following day. The telescope’s secondary mirror was then successfully mounted and latched on January 5, 2022.

James Webb Space Telescope
James Webb Space Telescope

Then, on January 8, 2022, NASA announced that the James Webb Space Telescope had successfully opened the giant primary mirror and was now fully deployed. The next step for Webb is to align the 18 individual mirrors that make up the observatory’s primary mirror. NASA estimates that the alignment could take up to 120 days of work after launch to complete.

The James Webb Space Telescope reached its final destination: L2, the second Sun-Earth Lagrange point, around which it will orbit on January 24, 2022, after traveling nearly a million miles (1.5 million km). Lagrange points are gravity points.
Rationally stable points in space.

James Webb Space Telescope images
The first science images from the James Webb Space Telescope were officially released by NASA during a live program on July 12 at 10:30 a.m. EDT (1430 GMT). These included cosmic rocks in the Carina Nebula, the striking Southern Ring Nebula, the Stephens Quintet, and an analysis of the atmospheric composition of the hot gas giant exoplanet WASP-96 b.

RELATED: James Webb Space Telescope’s First Images (cYeller)

“You know what I’m most excited about?” NASA Associate Administrator for Science Thomas Zurbuchen said during a ceremony after the images were revealed. “There are tens of thousands of scientists — and frankly, some of them born or not yet born — who are benefiting from this amazing telescope because it will be with us for decades.”

Related: Look! Here are the first amazing science photos from the James Webb Space Telescope.

A day earlier on July 11, 2022, President Joe Biden, Vice President Kamala Harris, and NASA Administrator Bill Nelson unveiled the first science-quality image obtained by the James Webb Space Telescope.

According to a statement from NASA, the stunning image shows the deepest infrared view of the universe ever seen and was made during just 12.5 hours of observation on one of the telescope’s four instruments.

The full image of the galaxy was taken by JWST.

The first publicly released science-quality image from NASA’s James Webb Space Telescope on July 11, 2022, is the deepest infrared view of the universe ever. (Image credit: NASA, ESA, CSA, and STScI)
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Ahead of the first image and data release, Webb has already treated us to several impressive images of his various devices being tested.

On February, 11. NASA announced (opens in new tab) that the James Webb Space Telescope has captured its first images of starlight. The first image taken by Webb was of a star called HD 84406. Light from the HD84406 was captured by 18 mirror sections of the web located on the primary mirror, resulting in a mosaic of 18 scattered bright dots.

The first published image taken by the James Webb Space Telescope on February 2, 2022, shows part of the mosaic created over 25 hours at the start of the process of aligning the 18 mirror segments of the James Webb Space Telescope.

The first published image taken by the James Webb Space Telescope on February 2, 2022, shows part of the mosaic created over 25 hours at the start of the process of aligning the 18 mirror segments of the James Webb Space Telescope. . (Image credit: NASA)
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“As the web aligns and comes into focus over the next few months, these 18 points will gradually become a star,” Thomas Zurbuchen, NASA’s associate administrator for the Science Mission Directorate, said on Twitter.

On 18 February. NASA released a new and improved image of HD84406, showing 18 unfocused copies of a star arranged in a deliberate hexagonal configuration. Once the observatory has successfully aligned the individual parts of the primary mirror, it will begin the image stacking process. This will overlay 18 images into a clear view.

Webb also took an impressive “selfie” using a special camera inside the NIRCam instrument. The camera is designed to be used for engineering and alignment purposes.

A “selfie” shows the 18 sections of the James Webb Space Telescope’s primary mirror as seen by a special camera inside the NIRCam instrument.

A “selfie” shows the 18 sections of the James Webb Space Telescope’s primary mirror as seen by a special camera inside the NIRCam instrument. (Image credit: NASA)
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In the “selfie” you can see that one segment of the mirror is brighter than the others because it is currently the only segment that is successfully aligned and pointing at the star. The remaining parts of the mirror were successfully assembled one by one.

On April 28, NASA announced in a statement (opens in a new tab) that the James Webb Space Telescope had completed its alignment phase after showing that all four of its science instruments were “crisp, well can get focused images from

NASA’s James Webb Space Telescope can now take sharp images of celestial objects with multiple instruments, the agency announced on April 28, 2022.

NASA’s James Webb Space Telescope can now take sharp images of celestial objects with multiple instruments, the agency announced on April 28, 2022. (Image credit: NASA/STScI)
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On July 11, 2022, President Joe Biden, Vice President Kamala Harris, and NASA Administrator Bill Nelson unveiled the first science-quality image obtained by the James Webb Space Telescope.

According to a statement from NASA (opens in new tab), the stunning image shows the deepest infrared view of the universe ever and was obtained using just 12.5 hours of observing time on one of the telescope’s four instruments. was made by doing

James Webb Space Telescope Science Mandate
JWST’s science mandate is pr.
Mainly divided into four areas:

First light and reionization

It refers to the early stages of the universe as we know it today, after the Big Bang. In the early stages after the Big Bang, the universe was a sea of ​​particles (such as electrons, protons, and neutrons), and the light was not visible until the universe cooled enough for these particles to coalesce. Another thing JWST will study is what happened after the first stars formed. This period is called the “realization period” because it refers to the time when neutral hydrogen was reionized by the radiation of these first stars.
was (made to be electrically charged again).

The 21.3-foot (6.5 m) diameter primary mirror of the James Webb Space Telescope.

The 21.3-foot (6.5 m) diameter primary mirror of the James Webb Space Telescope. (Image credit: NASA/C. Gunn)
Assembly of galaxies

Looking at galaxies is a useful way to see how matter is organized on a large scale, which in turn gives us clues about how the universe evolved. The spiral and elliptical galaxies we see today evolved from different shapes over billions of years, and one of JWST’s goals are to look back at the earliest galaxies to better understand this evolution. Scientists are also trying to figure out how we got the different types of galaxies we see today and the current methods of galaxy formation and assembly.
Part 3

Two weeks later, the Web Space Telescope is reshaping astronomy.

In the days since the Mega Telescope began delivering data, astronomers have reported exciting discoveries about galaxies, stars, exoplanets, and even Jupiter.
Image of a spiral galaxy stretched out with a ribbon of pink light.
The James Webb Space Telescope’s view of the galaxy NGC 7496 reveals bright channels of dust and gas where stars are actively forming.

NASA, ESA, CSA, and STScI
As President Biden unveiled the first image from the James Webb Space Telescope (JWST) on July 11, Massimo Pascal and his team sprang into action.

Slack, Pascal, an astrophysicist at the University of California, Berkeley, and 14 colleagues split the tasks. The image showed thousands of galaxies in a tiny patch of sky, some of which extended as light bent around the central cluster of galaxies. The team began examining the image, hoping to publish the first JWST science paper. “We worked non-stop,” Pascal said. “It was like an escape room.”

Three days later, minutes before the daily deadline on arxiv.org, the server where scientists can upload early versions of papers, the team presented their research. Pascal said he missed being 13 seconds early, “which was pretty funny.”

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The winners, Guillaume Mahler and colleagues at Durham University in the UK, analyzed the same first JWST image. “It was just an absolute joy to be able to take this amazing data and publish it,” Mahler said. “Why should we wait if we can be quick?”

The “healthy competition,” as Mahler calls it, highlights the tremendous amount of science already coming from JWST, as scientists begin receiving data from the long-awaited Infrared Sensing Mega Telescope.

The fascination of time
One of JWST’s most notable capabilities is its ability to peer back through time into the early universe and see some of the first galaxies and stars. Already, the telescope – which was launched on Christmas Day 2021 and is now 1.5 million kilometers from Earth – has seen the most distant, oldest galaxy.

A faint blob of light that is white in the center and red around the edges.]
A new galaxy called GLASS-z13, which is so distant that we see it as it appeared 300 million years after the Big Bang, now holds the record for the oldest galaxy. This record is not expected to last long.

Naidu et al., P. Oesch, T. Treu, GLASS-JWST, NASA/CSA/ESA/STScI
The two teams found the galaxy when they separately analyzed JWST observations for the GLASS survey, one of more than 200 science programs scheduled for the telescope’s first year in space. The two teams, one led by the Harvard-Smithsonian Center for Astrophysics in Massachusetts and the other by Marco Castellano at the Rome Astronomical Observatory, identified two particularly distant galaxies in the data: one as the distance that JWST detects light. ejected 400 million years after the Big Bang (a tie with the oldest galaxy seen by the Hubble Space Telescope) and another, named GLASS-z13, was observed as it was 300 million years after the Big Bang. Appeared years later. “This would be the most distant galaxy ever,” Castellano said.

Both galaxies appear extremely small, perhaps 100 times smaller than the Milky Way, yet they show amazing rates of star formation and already contain more than 1 billion times the mass of our Sun – the largest of these young galaxies. More than expected. one of you
NG galaxies even show evidence of a disc-like structure. Further studies will be conducted to isolate their light to gather their properties.

Another program in the early universe also became “incredibly distant galaxies,” said Rebecca Larsen, an astronomer at the University of Texas, Austin, and a member of the Cosmic Evolution Early Release Science (CERS) survey. A few weeks into the survey, the team has obtained a handful of galaxies from the first 500 million years of the universe, although Larsen and his colleagues have not yet released their exact results. “It’s better than I imagined and it’s just the beginning,” she said.

Image of thousands of galaxies of various shapes and colors.]
The telescope’s first public image shows a cluster of galaxies called SCalled MACS 0723, it is so massive that it scatters and amplifies light from galaxies outside of it.

NASA, ESA, CSA, and STScI
More early galaxies appear in the image of a galaxy cluster presented by President Biden and studied by Pascal and Mahler. Called SMACS 0723, the cluster is so massive that it bends the light of more distant objects, making them visible. Pascal and Mahler found 16 distant galaxies that are magnified in the image. Their exact ages are not yet known.

The telescope took a closer look at a distant galaxy in the image, a plume of light dating back 700 million years after the Big Bang. With its spectrograph, JWST detected heavy elements, especially oxygen, in the galaxy. Now scientists hope that the telescope will detect the absence of heavy elements in even earlier galaxies – evidence that these galaxies contain only Population III stars, the first hypothesized starsthe which are believed to be massive and composed entirely of hydrogen and helium. (Only when those stars exploded did they create heavier elements like oxygen and throw them into the universe.)

“We’re looking for galaxies where we don’t see any heavy elements,” said Andy Bunker, an astronomer at the University of Oxford. “This could be the smoking gun for the first generation of stars formed from early hydrogen and helium. Theoretically, they should exist. It just depends on whether they are bright enough.”

The composition of the galaxy

James Webb Space Telescope


For scientists seeking to understand the composition of galaxies and how stars form within them, JWST has already provided impressive data.

A diptych of images, one showing the Southern Nebula with a small box highlighting a nearby galaxy, and the other showing the galaxy up close.
JWST sees ribbon-like channels of star formation in the galaxy NGC 7496 that were previously shrouded in dust and therefore hidden in images taken by the Hubble Space Telescope.

NASA, ESA, CSA, and STScI
An observing program led by Janice Lee at the National Science Foundation’s NOIRLab in Arizona searches for young star-forming sites in galaxies. On behalf of Lee’s team, JWST observed a galaxy 24 million light-years away called NGC 7496, whose young star-forming regions are still shrouded in darkness. Hubble’s instruments were unable to penetrate the thick dust and gas that surrounded these regions. JWST, though, can see the infrared light that bounces off the dust, allowing the telescope to probe closer to the moments when stars turn on and ignite nuclear fusion in their cores. “The dust is shining,” Lee said.

Most notable, he said, is that NGC 7496 is a normal galaxy, “not a poster child galaxy.” Yet under the watchful eye of JWST, it suddenly comes to life and reveals channels where stars are forming. “It’s just extraordinary,” he said.

Astronomer John Barrentine of Dark Sky Consulting, a dark-sky conservation firm in Arizona, meanwhile, made another unusual discovery in one of the first JWST images. A telescope image of the Southern Ring Nebula, 2,500 light-years from Earth, showed remarkable clarity. On this side, an interesting edge-on galaxy (a unique location for studying the central bulge of the galaxy), previously misidentified as part of the nebula itself, came into view.

A comparison of the galaxy NGC 7496 with each other as seen by Webb and Hubble.]
JWST’s image of the Southern Ring Nebula showed a disk galaxy at its very edge. The unique vantage point allows scientists to study the structure of the galaxy’s central bulge.

NASA, ESA, CSA, and STScI
“We have this very sensitive machine that will reveal things we didn’t even know we were looking for,” Barentine said. “In almost every image on the web, the background is scrollable.”

Look at the stars and planets
Smaller targets are also in JWST’s crosshairs, including planets in our solar system. Jupiter appeared spectacularly as part of the first batch of images, which lasted just 75 seconds.

Astronomers know that Jupiter’s upper atmosphere is hundreds of degrees warmer than the lower atmosphere, but they aren’t sure why. By detecting infrared light, JWS
T could see the warm upper atmosphere glowing. It appears as a red ring around the planet. “We have this layer a few hundred kilometers above the cloud deck, and it’s glowing because it’s hot,” said Henrik Melen, a planetary scientist at the University of Leicester. “We’ve never seen anything like this on a global scale. It’s an extraordinary thing to see.”

Mellon’s program plans to use JWST in the coming weeks to study the driving force behind this atmospheric warming.

Jupiter appears purple with blue, and white streaks. A thin ring surrounds the planet, and one of its moons shines to its left
The mysterious, red-hot glow of Jupiter’s upper atmosphere is seen in JWST’s 75-second exposure of the planet. Also visible are Jupiter’s thin rings and its icy moon Europa, shining to the left. A small atmospheric disturbance visible on the lower edge of the planet’s volcanic moon IoIt is caused by interaction.

NASA, ESA, CSA, STScI, and Judy Schmidt


A JWST image of Jupiter shows the hidden volcanic moon Io interacting with Jupiter’s aurora – a small bump in the aurora. The image shows that “material coming from Io is driving down the magnetic field lines,” Mellon said. This effect has been seen before, but it was easily picked up by JWST with barely a glance at the planet.

JWST is also investigating planets in other star systems. Already, the telescope has glimpsed the famous TRAPPIST-1 system, a red dwarf star with seven Earth-sized worlds (some potentially habitable), though the data is still being analyzed. Preliminary observations have been released of a less hospitable planet, a “hot Jupiter” called WASP-96 b, in a tight 3.4-day orbit around its star.

JWST found water vapor in the planet’s atmosphere, confirming evidence of water a few days earlier by Cheema McGruder of the Harvard-Smithsonian Center and colleagues, who used a ground-based telescope. But JWST can go further; By looking at WASP-96 b’s carbon-to-oxygen ratio, it could solve a perplexing mystery about hot Jupiters: how they achieve such close orbits around their stars. More oxygen would suggest that the gas giant initially formed closer to the star, while a higher proportion of carbon would suggest that it formed in more carbon-rich regions.

Meanwhile, JWST may have seen a fleeting light in the sky — a short-lived event is known as a transient — that it wasn’t initially designed to do. Astronomer Mike Engeser and colleagues at the Space Telescope Science Institute (JWST’s operations center) in Baltimore, Maryland spotted a bright object that didn’t appear in Hubble images of the same region. They think it’s a supernova, or exploding star, about 3 billion light-years away — proof that telescopes can detect these events.

Related:
The Web Space Telescope will rewrite cosmic history. If it works.
An astronomer who observes the skies of other Earths.
Astronomers reimagine the formation of planets.
JWST should be able to find even more distant supernovae, giving it another way to serve as a probe of the early universe. It can also see stars being ripped apart by supermassive black holes that reside at the centers of galaxies, something no telescope has seen before. “For the first time we’ll be able to peer into these very deep, dark regions,” said Ori Fox, an astronomer at the Space Telescope Science Institute who leads the team studying the transients.

Transients, like other astronomical phenomena, are set to be redefined. After decades of planning and construction, JWST has taken off. The problem now plays out with the constant barrage of science from a machine so complex yet flawless it defies the belief that it was created by a human mind. “It’s working, and it’s crazy,” Larson said.

James Webb Space Telescope

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