Re: James Webb Space Telescope (JWST)
Posted: Sat Nov 19, 2011 5:37 am
I'm very glad that the James Webb Space Telescope was one of the winners.
Ann
Ann
APOD and General Astronomy Discussion Forum
https://asterisk.apod.com/
Members of the public can track the progress of the upcoming James Webb Space Telescope inside a NASA clean room, where the recently delivered Mid-Infrared Instrument (MIRI) will be integrated into the science instrument payload. Two cameras show the giant clean room at NASA's Goddard Space Flight Center in Greenbelt, Md. Online screen shots from the two clean-room cameras, affectionally dubbed "Webb-cams," are updated every minute.[img3="An image taken from one of NASA's two special "Webb-cam" cameras in a giant clean room at NASA's Goddard Space Flight Center in Greenbelt, Md. The Webb-cams focus on what's happening with the Mid-Infrared Instrument (MIRI), the very first completed instrument that will fly onboard the James Webb Space Telescope. The flight Integrated Science Instrument Module (ISIM) is at left center. The Ambient Optical Assembly Stand is on the right side of the image. (Credit: NASA/Chris Gunn)"]http://www.jpl.nasa.gov/images/miri/201 ... 2-full.jpg[/img3]
Developed by a consortium of 10 European institutions and NASA's Jet Propulsion Laboratory, Pasadena, Calif., and delivered by the European Space Agency, MIRI is the first Webb telescope instrument to be completed.
The clean room is generally occupied Monday through Friday from 5 a.m. to 1:30 p.m. PDT (8 a.m. to 4:30 p.m. EDT).
The Webb-cams can be seen online at: http://jwst.nasa.gov/webcam.html .
Of the James Webb Space Telescope's four science instruments, only MIRI can see light in the mid-infrared region of the electromagnetic spectrum. This unique capability will allow the Webb telescope to study physical processes occurring in the cosmos that the other Webb instruments cannot see.
MIRI's sensitive detectors will allow it to make unique observations of many things, including the light of distant galaxies, newly forming stars within our own Milky Way, and the formation of planets around stars other than our own, as well as planets, comets and the outermost debris disk in our own solar system.
The Webb Telescope project, managed at Goddard, is the world's next-generation space observatory and successor to NASA's Hubble Space Telescope. It is a joint project of NASA, the European Space Agency and the Canadian Space Agency.
For more information about MIRI and its arrival at NASA Goddard, visit: http://www.jpl.nasa.gov/news/news.cfm?release=2012-174 .
For more information about the James Webb Space Telescope, visit: http://www.jwst.nasa.gov .
The Independent Review Board (IRB) established by NASA to assess progress on its James Webb Space Telescope has unanimously recommended that development on the world’s premier science observatory should continue; NASA has established a new launch date for Webb of March 30, 2021.
A report issued by the review board addresses a range of factors influencing Webb’s schedule and performance, including the technical challenges and tasks remaining by primary contractor Northrop Grumman before launch.
Read the full report and NASA’s response at:
Reaching a major milestone, engineers have successfully connected the two halves of NASA’s James Webb Space Telescope for the first time at Northrop Grumman’s facilities in Redondo Beach, California. Once it reaches space, NASA’s most powerful and complex space telescope will explore the cosmos using infrared light, from planets and moons within our solar system to the most ancient and distant galaxies.
To combine both halves of Webb, engineers carefully lifted the Webb telescope (which includes the mirrors and science instruments) above the already-combined sunshield and spacecraft using a crane. Team members slowly guided the telescope into place, ensuring that all primary points of contact were perfectly aligned and seated properly. The observatory has been mechanically connected; next steps will be to electrically connect the halves, and then test the electrical connections. ...
Next up for Webb testing, engineers will fully deploy the intricate five-layer sunshield, which is designed to keep Webb’s mirrors and scientific instruments cold by blocking infrared light from the Earth, Moon and Sun. The ability of the sunshield to deploy to its correct shape is critical to mission success. ...
Good to see your dormancy has ended mjimih. Nice to hear from you.
the fine print on my prescription bottle?I wonder if they point it toward Earth; just what they will see?
It is... although the image is far from being purely optical. A lot of that "resolution" is the product of very sophisticated image processing, much of which depends upon already knowing what the image shows. Astronomical image processing enhances resolution using similar techniques, but less effectively since the guess about actual appearance is usually less precise.
It is great what modern imaging techniques can be applied these days!Chris Peterson wrote: ↑Fri Sep 27, 2019 12:37 pmIt is... although the image is far from being purely optical. A lot of that "resolution" is the product of very sophisticated image processing, much of which depends upon already knowing what the image shows. Astronomical image processing enhances resolution using similar techniques, but less effectively since the guess about actual appearance is usually less precise.
I'm really excited about the James Webb; and I wish it was in orbit already! I think it will really open up the nearby universe to really great knowledge of the neighboring stars as well as deep space!BaldEagle wrote: ↑Thu Dec 12, 2019 1:35 am Aside from looking deeper into space, what new revelations should we expect to see with the James Webb?
Will the Webb take us further toward the big bang and fine-tuning of the age of the Universe? If so, how far into the beginning of spacetime?
What will the various filtering show us? Will we be able to see into the center of galaxies?
Will the Webb allow us to see deeper into our own Milky Way galaxy?
How much improved detail can we expect viewing galaxies? Individual stars? And/or planets?
Thank you.
“I heard those questions once — as a matter of fact, I’ve heard a lot of questions in my time.BaldEagle wrote: ↑Thu Dec 12, 2019 1:35 am
Aside from looking deeper into space, what new revelations should we expect to see with the James Webb?
Will the Webb take us further toward the big bang and fine-tuning of the age of the Universe? If so, how far into the beginning of spacetime?
What will the various filtering show us? Will we be able to see into the center of galaxies?
Will the Webb allow us to see deeper into our own Milky Way galaxy?
How much improved detail can we expect viewing galaxies? Individual stars? And/or planets?
“And if, perchance, JWST never becomes operational...we’ll always have Hubble.”orin stepanek wrote: ↑Thu Dec 12, 2019 3:25 am
I'm really excited about the James Webb; and I wish it was in orbit already! I think it will really open up the nearby universe to really great knowledge of the neighboring stars as well as deep space!
I hope that doesn't happen! Isn't that a reason it's taking as long to git it up? To make sure everything is going to go as planed?neufer wrote: ↑Thu Dec 12, 2019 12:55 pm .
“And if, perchance, JWST never becomes operational...we’ll always have Hubble.”orin stepanek wrote: ↑Thu Dec 12, 2019 3:25 am
I'm really excited about the James Webb; and I wish it was in orbit already! I think it will really open up the nearby universe to really great knowledge of the neighboring stars as well as deep space!
orin stepanek wrote: ↑Thu Dec 12, 2019 8:11 pmI hope that doesn't happen! Isn't that a reason it's taking as long to git it up?neufer wrote: ↑Thu Dec 12, 2019 12:55 pm“And if, perchance, JWST never becomes operational...we’ll always have Hubble.”orin stepanek wrote: ↑Thu Dec 12, 2019 3:25 am
I'm really excited about the James Webb; and I wish it was in orbit already! I think it will really open up the nearby universe to really great knowledge of the neighboring stars as well as deep space!
To make sure everything is going to go as planed?![]()
https://en.wikipedia.org/wiki/Hubble_Space_Telescope wrote:
<<The JWST has a history of major cost overruns and delays which have resulted in part from outside factors such as delays in deciding on a launch vehicle and adding extra funding for contingencies. By 2006, $1 billion had been spent on developing JWST, with the budget at about $4.5 billion at that time. A 2006 article in the journal Nature noted a study in 1984 by the Space Science Board, which estimated that a next generation infrared observatory would cost $4 billion (about $7 billion in 2006 dollars). By October 2019, the estimated cost of the project had reached $10 billion for launch in 2021.>>
https://en.wikipedia.org/wiki/Hubble_Space_Telescope wrote:
<<By early 1986, the planned HST launch date of October that year looked feasible, but the Challenger accident brought the U.S. space program to a halt, grounding the Space Shuttle fleet and forcing the launch of Hubble to be postponed for several years. The telescope had to be kept in a clean room, powered up and purged with nitrogen, until a launch could be rescheduled. This costly situation (about US$6 million per month) pushed the overall costs of the project even higher. Furthermore, the ground software needed to control Hubble was not ready in 1986, and was barely ready by the 1990 launch.
Eventually, following the resumption of shuttle flights in 1988, the launch of the telescope was scheduled for 1990. On April 24, 1990, Space Shuttle Discovery successfully launched the telescope into its planned orbit during the STS-31 mission. From its original total cost estimate of about US$400 million, the telescope cost about US$4.7 billion by the time of its launch. Hubble's cumulative costs were estimated to be about US$10 billion in 2010, twenty years after launch.
Within weeks of the launch of the telescope, the returned images indicated a serious problem with the optical system. Although the first images appeared to be sharper than those of ground-based telescopes, Hubble failed to achieve a final sharp focus and the best image quality obtained was drastically lower than expected. Images of point sources spread out over a radius of more than one arcsecond, instead of having a point spread function (PSF) concentrated within a circle 0.1 arcsec in diameter, as had been specified in the design criteria.
Analysis of the flawed images revealed that the primary mirror had been polished to the wrong shape. Although it was probably the most precisely figured optical mirror ever made, smooth to about 10 nm (0.4 μin), the outer perimeter was too flat by about 2,200 nm. This difference was catastrophic, introducing severe spherical aberration, a flaw in which light reflecting off the edge of a mirror focuses on a different point from the light reflecting off its center.>>
Testing teams have successfully completed a critical milestone focused on demonstrating that NASA’s James Webb Space Telescope will respond to commands once in space.
Known as a “Ground Segment Test,” this is the first time commands to power on and test Webb’s scientific instruments have been sent to the fully-assembled observatory from its Mission Operations Center at the Space Telescope Science Institute (STScI) in Baltimore, Maryland.
Since reliably communicating with Webb when in space is a mission-critical priority for NASA, tests like these are part of a comprehensive regimen designed to validate and ensure all components of the observatory will function in space with the complex communications networks involved in both sending commands, and downlinking scientific data. This test successfully demonstrated the complete end-to-end flow from planning the science Webb will perform to posting the scientific data to the community archive. ...
In this test, commands to sequentially turn on, move, and operate each of Webb’s four scientific instruments were relayed from the Mission Operations Center. During the test, the observatory is treated as if it were a million miles away in orbit. To do this, the Flight Operations Team connected the spacecraft to the Deep Space Network, an international array of giant radio antennas that NASA uses to communicate with many spacecraft. However, since Webb isn’t in space yet, special equipment was used to emulate the real radio link that will exist between Webb and the Deep Space Network when Webb is in orbit. Commands were then relayed through the Deep Space Network emulator to the observatory, which is currently inside a Northrop Grumman clean room in Redondo Beach, California. ...
Well; l just read an article a couple of days ago; and the news clip said the launch date was moved from March to August; hope it wasn't moved again!Orca wrote: ↑Wed Jan 20, 2021 1:08 am I ran across a good article with updates on the status of the James Webb Space Telescope (JWST).
I remember reading about this project with excitement some 20 years ago. It’s an ambitious project even for today let alone when it was first seriously considered in the late ‘90s. Its primary mirror is quite a bit larger than Hubble (HST) – 6.5 m to HTS’s 2.4 m. The JWST will make use of a Lagrange point (L2 Earth-Sun) rather than being stuck in low Earth orbit, which means it has more of the sky available at any given time. And because it’s working in the infrared – near-infrared range JWST will cut through interstellar gas to peer further into the universe than is possible for HST. Perhaps most importantly, JWST’s sunshield looks vaguely like a Star Destroyer from some angles (the shield will keep the telescope at the near-zero temperatures required to be effective in the infrared ranges).
Unfortunately the project has been delayed, and delayed, and delayed again. But here we are in 2021 and it’s finally going to happen.
Probably.
https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#Cost_and_schedule_issues wrote:
<<As of July 2020, launch of the James Webb Space Telescopeis planned on 31 October 2021, on an Ariane 5 rocket from French Guiana. The observatory attaches to the Ariane 5 rocket via a launch vehicle adapter ring which could be used by a future spacecraft to grapple the observatory to attempt to fix gross deployment problems. However, the telescope itself is not serviceable, and astronauts would not be able to perform tasks such as swapping instruments, as with the Hubble Telescope. Its nominal mission time is five years, with a goal of ten years. JWST needs to use propellant to maintain its halo orbit around L2, which provides an upper limit to its designed lifetime, and it is being designed to carry enough for ten years. The planned five year science mission begins after a 6-month commissioning phase. An L2 orbit is only meta-stable so it requires orbital station-keeping or an object will drift away from this orbital configuration.>>