Last week included a trip to Edinburgh for STFC Council*. I arrived early (I recommend the night train, at least if you are within easy reach of Euston) and walked through Edinburgh in the mist to the UK Astronomy Technology Centre, which is nearly at the top of Blackford Hill to the south of the city centre. I’m not sure why it isn’t at the top of the hill, really. It is at the Royal…
love when things are named after people who had no idea about them. It's like 'RIP Euclid, you would have loved this group'
I think about this wrt the space probes named after the old school astronomers y'know. Like imagine explaining the Cassini-Huygens mission to Giovanni Cassini and Christiaan Huygens. Imagine explaining the Kepler Space Telescope to Johannes Kepler. Imagine explaining the Galileo probe to Galileo Galilei.
"Yeah we call the moons you saw the Galilean moons so when we sent a robot to look at them we named it after you"
every time something in astronomy happens im always like. why is this not trending on tumblr
#it’ll probably trend in the morning and then everyone will be like ‘there was an eclipse???’ 🙄 #brot posts#astro posting #between the eclipse and then also jwst launch and the fucking sgr a* picture its like #hello i know this is the blorbo website but cmon people 😔 #*pokes tumblr with a stick* cmon. talk about space
the reaization that i can upload my own things to redbubble and then buy them myself has been an absolute game changer in terms of gift giving
especially bc it removes my least favorite bit about making ppl stuff, which is mailing the stuff to them in a timely fashion
#basically every single person i know has received some sort of something made by me and printed by redbubble in the last year #it is especially funny bc all of these things are for different ppl so they are very different #there is absolutely no coherence #bees for me #and weird etruscan artifacts for my friend molly #and the jwst for aware #and now portuguese tile patterns for my mom #mea res
JWST has captured a new series of test images from a number of different sensors on the telescope, now that the main mirrors are all aligned, it was time to check these sensors an return some images, this time from the Large Magellanic Cloud, a dwarf galaxy around 150,000 light years from us.
NIRSPEC is a spectrograph rather than imager but can take images, the gaps in part of the image are shutters, which can be used to restrict the image to just certain segments.
The fine guidance sensor works similar to the guides you see on most telescopes, allowing you to see a wider frame and pinpoint the object you are wanting to really see.
NIRISS is focused to 1.5 microns
MIRI is focused at 7.7 microns, allowing emissions from gas as well as star light to be captured.
Finally NIRCAM (near infra red) is focused on 2 microns (in top image).
Bare in mind, these are all calibration images, meant to test the sharpness of each of the tools on the space telescope, the scientists involved have said these images have surpassed even their most optimistic hopes, and now JWST is in it's final preparation for stunning us with new images that will be for the next generation of astronomers, what Hubble has been for ours.
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, or minus 266 degrees Celsius).
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 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.
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.”
Yesterday, April 28th, 2022, NASA announced the completion of the seventh and final stage of the James Webb Space Telescope’s alignment. This also comes with the confirmation that Webb is capable of capturing crisp, well-focused images with all four of its onboard instruments.
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De spiegels van de Webb ruimtetelescoop zijn nu perfect uitgelijnd
De spiegels van de Webb ruimtetelescoop zijn nu perfect uitgelijnd
De zevende en laatste fase van het uitlijnen van de spiegels van de Webb ruimtetelescoop is afgerond en geslaagd. De spiegels van Webb zijn nu perfect in staat om haarscherpe foto’s te maken van hemelobjecten, zoals te zien is aan de foto hierboven. Dit betekent niet dat gestart kan worden met de wetenschappelijke waarnemingen, want nu krijg je nog de zogeheten ‘science…
As the James Webb Space Telescope nears active use, a lot of focus has been made on the single image released so far, and the galaxies billions of light years behind the star it was focusing on it. JWST of course, being an Infrared telescope, will be able to see much further back in time than Hubble, but it can also see things a little closer to home, and possibly the signature of life on planets orbiting nearby stars.
Plant life absorbs visible light, but in doing so, the light that is reflected back, can show this abortion, as it reflects near Infra Red light back fully. This pattern known as VRE (Vegetation Red Edge) can then be used to see if ground vegetation is indeed present. The above image taken of the south of Florida in false colours, uses green to highlight the extent of the VRE. Similar experiments have detected this as far off as the orbit of Jupiter.
James Webb of course is particularly well suited for detecting Infrared signals, and while it won't be taking fancy pictures of planets orbiting other stars, it may be possible to pick out the super faint reflective light from planets, and suggest the possibility of vegetation.
The first target is expected to be TRAPPIST-1, a system with a whole host of rocky planets within the so-called habitable zone. Because the star in this system is a red dwarf, the planets orbit much closer in, and therefore, have much smaller orbital years, allowing JWST to pick up when the planets pass between the Earth and the Star itself, and hopefully, make a detection of VRE.
Of course, there is a big assumption here, that life on planet Earth that evolved to take full advantages of our planets circumstances, will have followed a similar pattern else where. Detecting VRE may be a great way to spot planet Earth from the stars, but we've yet to see if it's a great way to spot life elsewhere.
MIRI, da's James Webb's koudste instrument, heeft de juiste temperatuur bereikt: 7 K (-266 °C)
MIRI, da’s James Webb’s koudste instrument, heeft de juiste temperatuur bereikt: 7 K (-266 °C)
Credit: NASA GSFC/CIL/Adriana Manrique Gutierrez
Met behulp van een zogeheten cryokoeler is het Mid-Infrared Instrument (MIRI) van de James Webb ruimtetelescoop afgekoeld tot z’n operationele temperatuur, dat is iets kouder dan 7 K (-266 °C). Die temperatuur werd op 7 april behaald en daarmee is ook MIRI nu klaar om met waarnemingen te beginnen, nou ja als de lenskap van MIRI er tenminste goed…