NASAs James Webb telescope successfully launched and deployed into space

[Wergeland]

not fair restricting it to Americans. the launch was on a European launcher .
And it's of interest to the whole world.

Yea i see you point.
It was US taxpayers who paid all the expenses so…

But i am sure images and data will be shared with facultys all over the world.

 

[Turingsage]

First images. I don't think the instruments have yet lowered their temperatures to their ideal working temp. that cooling is still taking place.

 

[F-22Raptor]

First images. I don't think the instruments have yet lowered their temperatures to their ideal working temp. that cooling is still taking place.

The size of the universe is mind-blowing. Each of those galaxies can hold millions or billions of stars and planets. Its beautiful and terrifying.

 

[Deino]

Still many things can go wrong

But the biggest hurdles are now already solved!

 

[Zarf]

The size of the universe is mind-blowing. Each of those galaxies can hold millions or billions of stars and planets. Its beautiful and terrifying.

All superlatives end at Universe.
I was always fascinated by the pictures taken by the hubble telescope now I cannot wait to see images from JW. It is one of the most exciting scientific project of my time. Even though the images will be in the IR spectrum. Hopefully, it will be no less exciting. I am sure humanity will know new things about the Universe.

 

[Aesterix]

But the biggest hurdles are now already solved!

Back in the days , I remember how bad they messed up with Hubble. Hence skeptical, still.

 

[Zarf]

First images. I don't think the instruments have yet lowered their temperatures to their ideal working temp. that cooling is still taking place.

Wow at 1:25 the galaxy NGC 7752 can be seen. Compare it to the result of Celestron C11 XLT here from the earth. Mind you it is not a cheap telescope for an individual.

 

[Hamartia Antidote]

Webb Space Telescope’s Coldest Instrument Reaches Operating Temperature Below Minus 447° F

NASA’s James Webb Space Telescope will see the first galaxies to form after the big bang, but to do that its instruments first need to get cold – really cold. On April 7, Webb’s Mid-Infrared Instrument (MIRI) – a joint development by NASA and ESA (European Space Agency) – reached its final operating

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Webb Space Telescope’s Coldest Instrument Reaches Operating Temperature Below Minus 447° F​

In this illustration, the multilayered sunshield on NASA’s James Webb Space Telescope stretches out beneath the observatory’s honeycomb mirror. The sunshield is the first step in cooling down Webb’s infrared instruments, but the Mid-Infrared Instrument (MIRI) requires additional help to reach its operating temperature. Credit: NASA GSFC/CIL/Adriana Manrique Gutierrez


NASA’s James Webb Space Telescope will see the first galaxies to form after the big bang, but to do that its instruments first need to get cold – really cold. On April 7, Webb’s Mid-Infrared Instrument (MIRI) – a joint development by NASA and ESA (European Space Agency) – reached its final operating temperature below 7 kelvins (minus 447 degrees Fahrenheit

Along with Webb’s three other instruments, MIRI initially cooled off in the shade of Webb’s tennis-court-size sunshield, dropping to about 90 kelvins (minus 298 F, or minus 183 C). But dropping to less than 7 kelvins required an electrically powered cryocooler. Last week, the team passed a particularly challenging milestone called the “pinch point,” when the instrument goes from 15 kelvins (minus 433 F, or minus 258 C) to 6.4 kelvins (minus 448 F, or minus 267 C).

“The MIRI cooler team has poured a lot of hard work into developing the procedure for the pinch point,” said Analyn Schneider, project manager for MIRI at NASA’s Jet Propulsion Laboratory in Southern California. “The team was both excited and nervous going into the critical activity. In the end it was a textbook execution of the procedure, and the cooler performance is even better than expected.”

The beam of light coming from the telescope enters MIRI through the pick-off mirror located at the top of the instrument and acting like a periscope. Then, a series of mirrors redirect the light toward the bottom of the instruments where a set of 4 spectroscopic modules are located. Once there, the beam of light is divided by optical elements called dichroics in 4 beams corresponding to different parts of the mid-infrared region. Each beam enters its own integral field unit; these components split and reformat the light from the whole field of view, ready to be dispersed into spectra. This requires the light to be folded, bounced, and split many times, making this probably one of Webb’s most complex light paths. To finish this amazing voyage, the light of each beam is dispersed by gratings, creating spectra that then projects on 2 MIRI detectors (2 beams per detector). An amazing feat of engineering!

The low temperature is necessary because all four of Webb’s instruments detect infrared light – wavelengths slightly longer than those that human eyes can see. Distant galaxies, stars hidden in cocoons of dust, and planets outside our solar system all emit infrared light. But so do other warm objects, including Webb’s own electronics and optics hardware. Cooling down the four instruments’ detectors and the surrounding hardware suppresses those infrared emissions. MIRI detects longer infrared wavelengths than the other three instruments, which means it needs to be even colder.
Another reason Webb’s detectors need to be cold is to suppress something called dark current, or electric current created by the vibration of atoms in the detectors themselves. Dark current mimics a true signal in the detectors, giving the false impression that they have been hit by light from an external source. Those false signals can drown out the real signals astronomers want to find. Since temperature is a measurement of how fast the atoms in the detector are vibrating, reducing the temperature means less vibration, which in turn means less dark current.

MIRI’s ability to detect longer infrared wavelengths also makes it more sensitive to dark current, so it needs to be colder than the other instruments to fully remove that effect. For every degree the instrument temperature goes up, the dark current goes up by a factor of about 10.

NASA testing the Webb telescope’s MIRI thermal shield in a thermal vacuum chamber at NASA’s Goddard Space Flight Center in Greenbelt, MD. Credit: NASA

Once MIRI reached a frigid 6.4 kelvins, scientists began a series of checks to make sure the detectors were operating as expected. Like a doctor searching for any sign of illness, the MIRI team looks at data describing the instrument’s health, then gives the instrument a series of commands to see if it can execute tasks correctly. This milestone is the culmination of work by scientists and engineers at multiple institutions in addition to JPL, including Northrop Grumman, which built the cryocooler, and NASA’s Goddard Space Flight Center, which oversaw the integration of MIRI and the cooler to the rest of the observatory.

“We spent years practicing for that moment, running through the commands and the checks that we did on MIRI,” said Mike Ressler, project scientist for MIRI at JPL. “It was kind of like a movie script: Everything we were supposed to do was written down and rehearsed. When the test data rolled in, I was ecstatic to see it looked exactly as expected and that we have a healthy instrument.”

There are still more challenges that the team will have to face before MIRI can start its scientific mission. Now that the instrument is at operating temperature, team members will take test images of stars and other known objects that can be used for calibration and to check the instrument’s operations and functionality. The team will conduct these preparations alongside calibration of the other three instruments, delivering Webb’s first science images this summer.

“I am immensely proud to be part of this group of highly motivated, enthusiastic scientists and engineers drawn from across Europe and the U.S.,” said Alistair Glasse, MIRI instrument scientist at the UK Astronomy Technology Centre (ATC) in Edinburgh, Scotland. “This period is our ‘trial by fire’ but it is already clear to me that the personal bonds and mutual respect that we have built up over the past years is what will get us through the next few months to deliver a fantastic instrument to the worldwide astronomy community.”

 

[hembo]

Problem Detected on the James Webb Space Telescope – MIRI Anomaly

By NASA SEPTEMBER 20, 2022

Webb MIRI Spectroscopy Animation

James Webb Space Telescope MIRI Spectroscopy Animation: The beam of light coming from the telescope is then shown in deep blue entering the instrument through the pick-off mirror located at the top of the instrument and acting like a periscope.
Then, a series of mirrors redirect the light toward the bottom of the instruments where a set of 4 spectroscopic modules are located. Once there, the beam of light is divided by optical elements called dichroics in 4 beams corresponding to different parts of the mid-infrared region. Each beam enters its own integral field unit; these components split and reformat the light from the whole field of view, ready to be dispersed into spectra. This requires the light to be folded, bounced, and split many times, making this probably one of Webb’s most complex light paths.
To finish this amazing voyage, the light of each beam is dispersed by gratings, creating spectra that then projects on 2 MIRI detectors (2 beams per detector). An amazing feat of engineering! Credit: ESA/ATG medialab

Mid-Infrared Instrument Operations Update
The James Webb Space Telescope’s Mid-Infrared Instrument (MIRI) has four observing modes. During setup for a science observation on August 24, a mechanism that supports one of these modes, known as medium-resolution spectroscopy (MRS), exhibited what appears to be increased friction. This mechanism is a grating wheel that allows astronomers to select between short, medium, and longer wavelengths when making observations using the MRS mode. Following preliminary health checks and investigations into the issue, an anomaly review board was convened on September 6 to assess the best path forward.

The Webb team has paused in scheduling observations using this particular observing mode while they continue to analyze its behavior. They are also currently developing strategies to resume MRS observations as soon as possible. The observatory is in good health, and MIRI’s other three observing modes – imaging, low-resolution spectroscopy, and coronagraphy – are operating normally and remain available for science observations.

The Mid-InfraRed Instrument (MIRI) of the James Webb Space Telescope (Webb) sees light in the mid-infrared region of the electromagnetic spectrum, at wavelengths that are longer than our eyes can see.

MIRI allows scientists to use multiple observing techniques: imaging, spectroscopy, and coronagraphy to support the whole range of Webb’s science goals, from observing our own Solar System and other planetary systems, to studying the early Universe.

To pack all these modes in a single instrument, engineers have designed an intricate optical system in which light coming from Webb’s telescope follows a complex 3D path before finally reaching MIRI’s detectors.

This artist’s rendering shows this path for MIRI’s imaging mode, which provides imaging and coronagraphy capabilities. It also contains a simple spectrograph. We first take a look at its mechanical structure with its three protruding pairs of carbon fiber struts that will attach it to Webb’s instrument compartment at the back of the telescope.

The pick-off mirror, acting like a periscope, receives the light from the telescope, shown in deep blue, and directs it into MIRI’s imaging module. Inside the instrument, a system of mirrors reformats the light beam and redirects it till it reaches a filter wheel where the desired range of mid-infrared wavelengths is selected from a set of 18 different filters each with its own specific function (the beam takes a light blue color in the animation).

Lastly, another set of mirrors takes the light beam coming out of the filter wheel and recreates the image of the sky on MIRI’s detectors.

Credit: ESA/ATG medialab