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James Webb: A $10bn machine in search of the end of darkness

Starboard primary mirror wing successfully deployed in the last few minute (latching to be completed).
JWST engineering ground test of starboard primary mirror wing deployment.
 
The NIRCam (near-infrared camera, ie 0.6-5 microns) focal plane array consists of ten 4 Mpixel detectors, so 40 Mpixel in total. There are smaller 1Mpixel detectors in other roles (eg part of the MIRI mid-infrared instrument, which covers 5-27 microns).
 
2hats said:
The NIRCam (near-infrared camera, ie 0.6-5 microns) focal plane array consists of ten 4 Mpixel detectors, so 40 Mpixel in total. There are smaller 1Mpixel detectors in other roles (eg part of the MIRI mid-infrared instrument, which covers 5-27 microns).
Click to expand...
Blimey, my own Nikon has a 36mpx chip, I was expecting more, but I guess it isn't necessary.
 
weltweit said:
Blimey, my own Nikon has a 36mpx chip, I was expecting more, but I guess it isn't necessary.
Click to expand...
Your Nikon doesn't work at those ultra low light levels (and temperatures) in the infra-red. Bear in mind that resolution is a function of wavelength too.

In separate news, JWST engineers reckon the fuel saving courtesy the Ariane 5 launch has potentially doubled the lifetime of the observatory. (Speculation is that other elements such as the MIRI cryocooler will likely fail before that, but potentially some science observations could carry on for that long).
 
You can follow the mirror deployments here. Exciting.

84C5A1C1-7CF2-46A7-8923-A00D484FC1CE.png



www.jwst.nasa.gov

Deployment Explorer Webb/NASA

Interactively explore Webb's deployments on this page. Webb is NASA's largest and most powerful space science telescope ever constructed. Webb’s enormous size and frigid operating temperature present extraordinary engineering challenges. After launching from French Guiana, the observatory will...
www.jwst.nasa.gov
 
Have just noticed that they've switched up to the high gain (Ka band) antenna now for data downlink. Currently being exercised at its lowest rate, 7 Mbps, but is selectable up to 28 Mbps.

SE L2 liberation point orbit insertion burn, MCC-2, due this coming evening (around 1900UT, 24 Jan).
 
MCC-2 (4m 57s burn providing a delta-V of 1.6 m/s) has just been confirmed to have been executed. JWST is now in a libration point 'halo' orbit about Sun-Earth L2. Full chilldown to operating temperature and mirror alignment will begin shortly. The Ariane 5 upper stage should shoot past L2 into a heliocentric orbit over the next day or so.
 
The JWST is now mirror aligned across all science instruments and early engineering images have been released, including a comparison with the previous generation of IR space telescope (Spitzer). Imaging is purely diffraction limited (ie optimal IR optical performance has been achieved for this size of telescope).
Engineering image depicting the relative arrangement of each of the JWST imaging instruments in the telescope focal plane (each slightly offset on the sky with respect to one another). Dark region 'structures' in the NIRSpec image are due to thousands of microshutters in the light path which are present to precisely (de)select individual targets for spectroscopy.
7.7 µm MIRI test image of a LMC region compared to the same field of view as seen by the Spitzer Space Telescope (at 8 µm).

Science instrument commissioning has begun (to test combinations of lenses, masks, filters and shutters). This includes calibration work that involves a thermal slew procedure - to determine how the performance profile (stability) varies with attitude pointing (as the observatory pitches between 'hot' and 'cold' attitudes).
JWST 'hot' and 'cold' attitude illustrations.

If all goes to plan, once that is complete (around the second half of June) the Cycle 1 GO (General Observers) observations will commence and shortly thereafter early release observations should be available.
www.esa.int

Webb in full focus

Webb in full focus
www.esa.int
www.esa.int

MIRI and Spitzer comparison image

www.esa.int
 
2hats said:
Webb's First Deep Field - a NIRCam composite of galaxy cluster SMACS 0723. Note the gravitational lensing arcs. Oldest/furthest galaxies yet seen in the infrared. The field of view is roughly equivalent to the area of sky covered by holding a grain of sand out at arm’s length.
Webb's First Deep Field - a NIRCam composite of galaxy cluster SMACS 0723, featuring gravitational lensing arcs.'s First Deep Field - a NIRCam composite of galaxy cluster SMACS 0723, featuring gravitational lensing arcs.
High resolution version (30MB) to dive into.​
More to follow tomorrow.
Click to expand...
It's amazing and unfathomable and beautiful
 
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