The observatory's MIRI instrument needs to cool down almost to absolute zero, the temperature where the motion of atoms stops before it can start observing the universe.

The James Webb Space Telescope continues to cool down as it prepares to take its first scientific images of the distant universe this summer. One instrument, in particular, needs some extra help to accomplish the task.

In its location, at Lagrange Point 2, some 1.5 million kilometers from Earth, hidden behind the planet and a giant sun-shield, the James Webb Space Telescope is freezing.

The mission was carefully designed to keep the telescope's mirrors and instruments at a constant and extremely low temperature of minus 369.4 degrees Fahrenheit (minus 223 degrees Celsius).

This is important because Webb observes the universe in the warmth-carrying infrared wavelengths of the electromagnetic spectrum, and any heat from the telescope itself would dazzle its detectors.

For the telescope's Mid-InfraRed Instrument (MIRI), however, even that temperature is not cold enough. The instrument's detectors require an even colder temperature of minus 266 degrees C, only 7 degrees C above absolute zero, the temperature where the motion of atoms stops.

Webb, therefore, has a cryocooler to help MIRI cool down. The cryocooler is essentially a "sophisticated refrigerator," NASA said in a statement, which actively cools MIRI. Refrigerant is cooled in a system of tubes via conduction, after which it's pumped through the instrument to keep it cold. The cryocooler doesn't consume coolant, so it can operate throughout the lifespan of its technical components.

Once operational, MIRI will be able to detect the light of the most distant stars in the universe but also peer through dust clouds within our galaxy, the Milky Way, to witness how stars form.

"Webb's infrared sensitivity allows us to understand what happens at these very first stages, as gas and dust are actively collapsing to form new stars," Klaus Pontoppidan, the Space Telescope Science Institute project scientist for Webb, said in the statement.

The Telescope Is Also Prepare Other Work While Waiting For MIRI To Cool Down

Last week, the observatory performed a thruster burn to maintain its orbit around the second Lagrange point. It was the second such maneuver since Webb's arrival at its destination — similar burns will continue throughout the observatory's lifetime. (sekarangsayatahu/james-webb)

The James-Webb Space Telescope is being calibrated and should be operational in the coming months. He will then be responsible for observing various astronomical objects, including exoplanets. Thanks to its unparalleled precision, the JWST will thus be able to detect atmospheric pollution from a distant planet, which could be synonymous with civilization.

James-Webb Space Telescope's (JWST) mission is just beginning, but its program is already full! The new observatory launched by NASA and the European Space Agency ( ESA ) entered orbit around the Lagrange point L2, located 1.5 million kilometers from Earth, on January 24, 2022. If the deployment of its instruments had begun when it was transported into space, the results of the first calibrations have been known since February 11. Thus, the James Webb Space Telescope (JWST) proceeded to observe the star HD 84406. The impressive 6.5-meter mirror in diameter seems to be functional and will be able to examine nebulae, galaxies, and exoplanets over the next few months.

Engineers from NASA, ESA, and Northrop Grumman insisted: the capabilities of the JWST should change the future of space observation, thanks to instruments of incredible precision. Regarding the observation of exoplanets, James-Webb will be able to collect data on the atmosphere of some of these distant worlds, offering tools to scientists to study the composition of said planets. As Universe Today magazine points out, in an article published on February 21, the JWST will even be able to analyze the level of air pollution. A track to discover new civilizations?

Observing pollution to detect a civilization

The Universe Today article is based on a study published on February 11 on ArXiv, explaining that the detection of certain chemical signatures could indicate the presence of potentially industrial civilizations. Chlorofluorocarbon ( CFC ), fluorinated gas mainly used in refrigeration, is in the sights of astrophysicists in search of extraterrestrial life. On Earth, CFCs cause atmospheric alteration, notably damaging the ozone layer. Some countries have also limited their use of CFCs to slow down the heavy pollution resulting from them.

The James Webb Space Telescope (JWST) is an international 21st-century space observatory (Mainly NASA & ESA) that was launched on 25 December 2021.is intended to be the premier observatory of the 2020s, combining the largest mirror yet on a near-infrared space telescope with a suite of technologically advanced instruments from around the world.

The telescope is designed to last at least five and a half years (six months calibration plus five years science operations), but with a goal of ten years. The limiting factor is expected to be fuel to maintain its halo orbit, of which there is enough for at least ten years.

It was announced in December 2021 that due to the accuracy of the orbital insertion and course correction burns the telescope had more fuel available than originally planned and could operate for "significantly" longer than the original 10 year planned life span.

JWST is expected to cost at least $8.8 billion, including design, construction, and five years of operations (does not include extended mission funding) or International contributions.

---

Timeline

• 1996: Next Generation Space Telescope initiated.

• 2000: NEXUS cancelled (JWST technology demo).

• September 2002: NGST named James Webb Space Telescope.

• 11 September 2003: $824.8 million prime contract for JWST awarded to TRW.

• January 2007: 9/10 technology development items pass non-advocate review.

• April 2010: technical part of Mission Critical Design Review (MCDR) passes.

• July 2011: James Webb project threatened with cancellation.

• November 2011: JWST survives cancellation attempt.

• 2012: MIRI instrument hand-off.

• March 2013: FGS/NIRISS installed in the Integrated Science Instrument Module (ISIM).

• 4 July 2013: MIRI installed in ISIM.

• March 2014: NIRCam installed in ISIM

• 24–25 March 2014: NIRSpec integrated into ISIM.

• June 2014: first combined test of all four instruments including cryogenic testing in the Goddard Space Environment Simulator.

• 2014: peak U.S. funding hit $650 million this year.

• February 2015: hexagonal segments of the primary mirror completed.

• December 2015: contract for JWST's launcher signed with a launch date of October 2018.

• March 2016: cryogenic testing of instruments and mirrors completed.

• 3 March 2016: secondary mirror installed on OTE.

• March 2016: Aft Optics Subsystem installed on OTE.

• November 2016: JWST construction completed, with additional testing to come.

• January 2017: JWST is fine after experiencing an anomaly during vibration testing in Dec 2016.

• 27 March 2018: JWST launch delayed to at least May 2020 as issues arise, including ones with the propulsion system and potential snagging of the sunshield.

• 27 June 2018: JWST launch postponed to 30 March 2021 based on recommendations by an Independent Review Board.

• 16 July 2020: JWST launch postponed to 31 October 2021 due to the impacts of the COVID-19 pandemic as well as technical challenges.

• 1 June 2021: JWST launch postponed to no earlier than November 2021 due to concerns regarding the readiness of the Ariane 5 launch vehicle and launch site.

• 8 September 2021: JWST launch postponed to 18 December 2021.

• 22 November 2021: JWST launch delayed to no earlier than 22 December 2021, to allow additional testing after experiencing vibrations due to an unplanned clamp release.

• 15 December 2021: JWST launch delayed to no earlier than 24 December 2021, due to an electrical fault, resulting in a communications error between the observatory and the Launch Vehicle.

• 21 December 2021: JWST launch delayed to no earlier than 12:20 UTC on 25 December 2021, due to adverse weather conditions at the launch site.

• 25 December 2021: liftoff at 12:20 UTC.

Pre-launch plans

• 2016: OTE tests complete.

• 2017: OTIS tests complete.

• 2017: Spacecraft (including sunshield) tests complete.

• 2018: Observatory I&T complete.

• October 2018: planned launch date as of 2016.

• Early 2019: planned launch date as of October 2017.

• May 2020 or later: planned launch date as of March 2018.

• 30 March 2021: planned launch date as of June 2018.

• 31 October 2021: planned launch date as of July 2020.

• November 2021 or later: planned launch date as of June 2021.

• 22 December 2021: planned launch date as of November 2021.

• 24 December 2021: planned launch date after delay due to communication issues between the observatory and the Launch Vehicle.

• 25 December 2021: final launch date after delay due to forecasts of unfavorable weather during the launch window on 24 December.

After-launch plans

• After launch, JWST was unfolded in the following planned order.

  1. spacecraft appendages (solar arrays, high gain antenna)

  2. sunshield

  3. extend tower

  4. secondary mirror

  5. primary mirror

• For 29 days after launch, JWST took a 1.51 million kilometer (940,000 mile) trajectory to L2 halo orbit.

• For six months JWST prepares for full-time science operation. This includes letting all instruments cool down, calibrating the mirrors and instruments, and other procedures.

• Five-year science mission starts after six months (planned)

• 10 years of operation goal, and enough fuel to maintain halo orbit for at least ten years is included

Source Wikipedia and sekarangsayatahu James Webb 101 Linimasa