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Home / Science / Launch of NASA Telescope Celebrated as Hubble Follower Until 2020

Launch of NASA Telescope Celebrated as Hubble Follower Until 2020



NASA has stated that the launch of the James Webb Space Telescope (JWST), the agency's most ambitious space mission, was advanced at the earliest in May 2020, as evidenced by [196592002] this delay The increase in costs and technical failure could cause the telescope to exceed the US $ 8.8 billion budget ceiling (including operating charges once the telescope is in space)

delay announced in September 2017 had postponed the start date of the telescope from October 2018 to spring 2019.

The JWST, colloquially called Hubble Space Telescope "Successor" is designed to study the universe in the infrared spectrum of the EM spectrum. Among other things, it tries to capture " first light ", the light of the first stars of the universe.

  A comparison of the mirrors of the Hubble Space Telescope and the James Webb Space Telescope. Credit: NASA

A comparison of the mirrors of the Hubble Space Telescope and the James Webb Space Telescope. Credit: NASA

For this, the telescope requires a primary mirror larger than the one on the Hubble. The primary mirror "collects" radiation from space and focuses it on research instruments; The larger the mirror, the more data the telescope can analyze. Launched in 1990, the Hubble was revolutionary in its day with a 2.4-meter-wide mirror. India's AstroSat has a 30 cm wide mirror. However, the JWST has a 6.5 m wide mirror. In contrast to its predecessors, the mirror is not a single piece, but an arrangement of 18 hexagonal light gold-plated beryllium plates .

Another difference between the two space telescopes is that the Hubble was located. The JWST is in a low orbit around the Earth, a feature that allowed NASA to "wait" for it. It is located at a point in space about 1.5 million kilometers from Earth past the lunar orbit called Lagrange Point 2 . Therefore, the agency can not operate the satellite should something go wrong after launching.

The JWST Ensemble also has a large shield that blocks the sun and ensures that the star's light does not overstrain the telescope's instruments and keep the assembly cool (the ideal operating temperature of the JWST device is the same.) Average temperature on the surface of Pluto: -223 ºC). It consists of an ultra-thin film of a material called Kapton and is about the size of the surface of an Olympic swimming pool.

Overall, the telescope is launched with an Ariane 5 rocket. [19659021] Problems in abundance for JWST

NASA admitted on March 27 that integration and testing took longer than planned, but that they wanted to successfully launch the mission. The final stages of assembly, integration, and testing are underway by Northrop Grumman, NASA's chief contributor to JWST, located in Redondo Beach, California. The Authority built and assembled the primary mirror and scientific payload and delivered it to Northrop in February.

One of the main problems with the construction of the JWST was the Kapton films. Engineers discovered several cracks indicating poor processing. Part of the shield stalled during a test, which resulted in seven [235,400] tears [2,959,007] including two 10 cm long, forcing the team to change the way in which it would be packed into the rocket.

Other avoidable issues the team faced were damage to the propulsion system due to the use of a wrong solvent that had to be repaired after three months. Applying a voltage higher than necessary, damaging the transducers; and improper cleaning of valves in the engines, leading to leaks that took nearly a year to repair.

  The Sun Shield for the James Webb Space Telescope. Each membrane is as thick as a single human hair strand. Credit: NASA

The Sun Shield for the James Webb Space Telescope. Each membrane is as thick as a single human hair strand. Credit: NASA

To compensate for these delays, Northrop started working around the clock – but that was not enough because it could not work on different telescope components at the same time. The additional work brought the expenses for the telescope dangerously close to the upper limit of 8.8 billion dollars.

However, the team is determined to make everything work, probably because the JWST has grown too big to fail. " Webb is the highest priority project for the Science Mission Directorate of the Authority" according to Robert Lightfoot, Acting NASA Administrator. "The issues raised by the spacecraft element prompt us to take the necessary steps to focus our efforts on completing this ambitious and complex observatory."

Implications for Science

A decade-long survey conducted in [2,990,023] [19659002] welcomed JWST as NASA's important future space mission (these investigations, according to Marcia Rieke, an astronomer at the University of Arizona are "a measure of what is actually achievable") The delays, however, have raised questions whether the 2020 Decadal Survey should be postponed. Thomas Zurbuchen, NASA's associate administrator for science, had asked, " Should that happen if we have real Webb data in our hands or before?"

Moving the Decadal Astronomy Survey could also impact 19659002 surveys in other areas, such as the planetary sciences. NASA currently has two options: to ignore the telescope and do the survey or wait for the telescope to work. Either way, the way forward seems unclear.

Some researchers also believe that the scientific community has put a lot of effort and money into the JWST, so much so that there is no other option for the mission than being successful. 19659060] A graph of the rising costs and delayed start data of the James Webb Space Telescope. Credit: Twitter / Francesca Civano "width =" 566 "height =" 368 "srcset =" https://cdn.thewire.in/wp-content/uploads/2018/03/29231129/JWST_launch-date-and-cost_Twitter_Fransesca- Civano.jpg 566w, https://cdn.thewire.in/wp-content/uploads/2018/03/29231129/JWST_launch-date-and-cost_Twitter_Fransesca-Civano-300×195.jpg 300w "sizes =" (max-width: 566px) 85vw, 566px "/>

A graph of rising costs and delayed start data from the James Webb Space Telescope Credit: Francesca Civano / Twitter

Others disagree David Sterling, an astrophysicist at Princeton University, said Scientific American " We are all disappointed; Many of us are eagerly awaiting Webb's science. However, it is better to have a modest delay and a modest excess (as a fraction of the cost of Webb) and to have a successful mission.

Even others have speculated that JWST's problems could prevent future investment in large telescopes and turn the tables in favor of smaller, lower-risk telescopes, but in the short term, even this transition is unlikely.

Similarly, NASA scientists had Planned to increase funding for the Wide Field Infrared Surveying Telescope (WFIRST) as soon as the JWST's claims abate. WFIRST is expected to be able to answer questions in infrared astrophysicists and conduct research in Referring to dark energy and exoplanets. However, with JWST on the horizon at least until 2020, the WFIRST mission must free itself of some of its resources

This is not the first major roadblock of WFIRST Earlier President Donald Trump proposed to cancel the project Following protests from the scientific community, the Congress restored it along with an allocation of $ 150 million.

However, thanks to JWST's delay and limitation of congressional spending, WFIRST may delay . This is disturbing because the WFIRST was originally intended to work with the JWST to decode the oldest mysteries of the universe.


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