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Webb space telescope to launch Dec. 18 – Design ENGINEERING

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(Photo credit: NASA)

MONTREAL – In just over a month, the world’s largest, most advanced telescope will be launched into orbit from a spaceport in South America, and among those eagerly watching will be Montreal physics professor Rene Doyon.

The James Webb Space Telescope is scheduled to blast off Dec. 18 aboard the Ariane 5 rocket from the Guiana Space Center in French Guiana. The orbiting infrared observatory, a collaboration between NASA and the European and Canadian space agencies, will be 100 times more powerful than its predecessor, the Hubble Space Telescope launched in 1990.

It will feature two Canadian components: a fine guidance sensor that will help it stay locked on target, and an instrument called a Near-Infrared Imager and Slitless Spectrograph, or NIRISS, that will help study astronomical objects, from exoplanets to distant galaxies.

Doyon, a physics professor at Universite de Montreal, is the principal investigator of the Canadian-built tools and has been working toward this for 20 years. He said it’s both an exhilarating and a fretful time.

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Before the massive telescope starts to work, there will be plenty of tense moments. The two weeks immediately after launch will be critical as the telescope unfurls in an elaborate sequence described by NASA engineers during a recent briefing as an origami exercise.

“It’s what we call the 14 days of terror – the time it takes to deploy the telescope – but I’m very confident,” Doyon said in a recent interview. “We’ve tested this and retested, so there’s good reason to believe everything is going to be fine.”

The telescope, named after the former NASA administrator who led the Apollo lunar exploration program, has been folded compactly for launch, and thousands of parts must work to allow it to unfold properly. It will be operated at a distance of 1.5 million kilometres from Earth, too far to be serviced as was possible with Hubble, which was just 500 kilometres away.

The instruments on the Webb telescope can only function properly at a very low temperature – minus 233 degrees C – so one of its components is a sunscreen the size of a tennis court that will shield it from the heat of the sun and the light of the Earth and moon.

Canada’s contribution means that when the telescope is ready to operate – expected around the middle of next year – the country is guaranteed at least five per cent of the telescope’s available observation time. Of 286 proposals accepted worldwide for the first year of use, 10 will have Canadians as the principal investigators.

Many have been waiting eagerly for Webb’s launch, which has been delayed several times. Doyon said Webb’s infrared wavelength viewing capabilities mean scientists will be able to see some things for the first time, like the first stars and galaxies from the early universe after the Big Bang. It will also represent a huge leap for the study of exoplanets – planets outside our solar system – to probe their atmospheres for clues of early life.

Sarah Gallagher, science adviser at the Canadian Space Agency, said it’s an exciting time.

“It’s the culmination of decades of work by really talented people, and I’m so proud of our Canadian contribution, the scientific one and the industrial one. I think it really showcases the strength of our community,” she said in an interview. “We have people who want to study bodies in our solar system, planets around other stars, galaxies in the very early universe and all sorts of different topics.”

Among them will be Loic Albert, who will be able to continue his work on brown dwarfs – essentially failed stars. The project involves looking for companions for about 20 of them, and he will use Webb’s sensitivity to his advantage.

“In my case, James Webb opens the possibility of studying some specific types of brown dwarfs, the coldest and the least massive brown dwarfs. They are so faint that you can’t observe them from the ground,” said Albert, a researcher at Universite de Montreal and a scientific instrument expert for Webb.

Albert says scientists who’ve been studying exoplanets using Hubble’s limited capability should reap the rewards of Webb. “For the exoplanet community, it’s going to be a game changer,” he said in an interview. “It’s going to allow measuring exoplanet atmospheres for a large number of planets and at exquisite detail.”

Doyon, who is planning to travel to French Guiana for the launch next month, said the prospect of unintended discoveries is the most exciting part ahead of Webb’s launch.

“Every time a new telescope is started, history shows that after five or 10 years, you ask the question, what was the biggest discovery the telescope did. It’s something that was not planned,” he said. “I’m sure Webb will be the same.”
https://jwst.nasa.gov

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Doing Photon Upconversion A Solid: Crystals That Convert Light To More Useful Wavelengths – Eurasia Review

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Solid-solution organic crystals have been brought into the quest for superior photon upconversion materials, which transform presently wasted long-wavelength light into more useful shorter wavelength light. Scientists from Tokyo Institute of Technology revisited a materials approach previously deemed lackluster—using a molecule originally developed for organic LEDs—achieving outstanding performance and efficiency. Their findings pave the way for many novel photonic technologies, such as better solar cells and photocatalysts for hydrogen and hydrocarbon productions.

Light is a powerful source of energy that can, if leveraged correctly, be used to drive stubborn chemical reactions, generate electricity, and run optoelectronic devices. However, in most applications, not all the wavelengths of light can be used. This is because the energy that each photon carries is inversely proportional to its wavelength, and chemical and physical processes are triggered by light only when the energy provided by individual photons exceeds a certain threshold.

This means that devices like solar cells cannot benefit from all the color contained in sunlight, as it comprises a mixture of photons with both high and low energies. Scientists worldwide are actively exploring materials to realize photon upconversion (PUC), by which photons with lower energies (longer wavelengths) are captured and re-emitted as photons with higher energies (shorter wavelengths). One promising way to realize this is through triplet-triplet annihilation (TTA). This process requires the combination of a sensitizer material and an annihilator material. The sensitizer absorbs low energy photons (long-wavelength light) and transfers its excited energy to the annihilator, which emits higher energy photons (light of shorter wavelength) as a result of TTA (Figure 1).

Finding good solid materials for PUC has proven challenging for a long time. Although liquid samples can achieve relatively high PUC efficiency, working with liquids, especially those comprising organic solvents, is inherently risky and cumbersome in many applications. However, previous trials to create PUC solids generally suffered from poor crystal quality and small crystal domains, which lead to short travelling distances of triplet excited states and thus, low PUC efficiency. Additionally, in most previous solid PUC samples, stability under continuous photoirradiation was not tested and experimental data were often acquired in inert gas atmospheres. Hence, the low efficiency and insufficient materials stability had been of concern for a long time.

Now, in a recent study led by Associate Professor Yoichi Murakami from Tokyo Tech, Japan, a team of researchers found the answer to this challenge. Published in Materials Horizon, their paper (open access) describes how they focused on van der Waals crystals, a classical materials class that has not been considered for the quest of high-efficiency PUC solids. After discovering that 9-(2-naphthyl)-10-[4-(1-naphthyl)phenyl]anthracene (ANNP), a hydrocarbon molecule originally developed for blue organic LEDs, was an excellent annihilator for embodying their concept, they tried mixing it with platinum octaethylporphyrin (PtOEP), a staple sensitizer that absorbs green light.

The team found that aggregation of the sensitizer molecules could be completely avoided by utilizing the crystalline phase of a van der Waals solid solution with a sufficiently low proportion of PtOEP to ANNP (around 1:50000). They proceeded to thoroughly characterize the obtained crystals and found some insight into why using the ANNP annihilator prevented the aggregation of the sensitizer when other existing annihilators had failed to do so in previous studies. Moreover, the solid crystals the team produced were highly stable and exhibited outstanding performance, as Dr. Murakami remarks: “The results of our experiments using simulated sunlight indicate that solar concentration optics such as lenses are no longer needed to efficiently upconvert terrestrial sunlight.”

Overall, this study brings van der Waals crystals back into the game of PUC as an effective way of creating outstanding solid materials using versatile hydrocarbon annihilators. “The proof-of-concept we presented in our paper is a major technical leap forward in the quest for high-performance PUC solids, which will open up diverse photonics technologies in the future,” concludes Dr. Murakami. Let us hope further research in this topic allows us to efficiently transform light into its most useful forms.

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New Russian module docks with International Space Station – CGTN

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A Soyuz rocket carrying the Progress cargo spacecraft and the Prichal node module lifts off from a launch pad at the Baikonur Cosmodrome, Kazakhstan, November 24, 2021. /CFP

A Soyuz rocket carrying the Progress cargo spacecraft and the Prichal node module lifts off from a launch pad at the Baikonur Cosmodrome, Kazakhstan, November 24, 2021. /CFP

A Russian cargo craft carrying a new docking module successfully hooked up with the International Space Station Friday after a two-day space journey.

The new spherical module, named Prichal (Pier), docked with the orbiting outpost at 6:19 p.m. Moscow time (1519 GMT). It has six docking ports and will allow potential future expansion of the Russian segment of the station.

The module has moored to the docking port of the new Russian Nauka (Science) laboratory module.

On Wednesday, a Soyuz rocket took off from the Russian launch facility in Baikonur, Kazakhstan, carrying the Progress cargo ship with Prichal attached to it. After entering space, the cargo ship with the module went into orbit.

Progress is also delivering 700 kilograms of various cargoes to the space station and is expected to undock from the station on December 22.

The first Soyuz spacecraft is expected to dock at the new module on March 18, 2022, with a crew of three cosmonauts: Oleg Artemyev, Denis Matveev and Sergei Korsakov.

Earlier this week, the Russian crew on the station started training for the module’s arrival, simulating the use of manual controls in case the automatic docking system failed.

The space outpost is currently operated by NASA astronauts Raja Chari, Thomas Marshburn, Kayla Barron, and Mark Vande Hei; Russian cosmonauts Anton Shkaplerov and Pyotr Dubrov; and Matthias Maurer of the European Space Agency.

Source(s): AP

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Stargazer in Italy spots NASA's DART asteroid impact probe in night sky after launch – Space.com

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An Italian telescope captured NASA’s asteroid-smashing mission shortly after its launch into space this week. 

A new image and video, taken by the Elena telescope located in Ceccano, Italy, shows NASA’s Double Asteroid Redirection Test mission, also known as DART, separated from the second stage of the Falcon 9 rocket which launched the spacecraft from Vandenberg Space Force Base in California on Tuesday (Nov. 23 PST, or early Nov. 24 EST) . The mission sent DART on a 10-month-long journey to a binary asteroid system called Didymos

Both DART and the booster can be seen in this image (above), which was taken remotely with a single 30-second exposure, astronomer Gianluca Masi said in a statement. Masi runs the Virtual Telescope Project 2.0, which includes the Elena telescope.

The image was taken remotely 10 hours after DART lifted off, Masi said.

Related: NASA’s DART asteroid-impact mission explained in pictures

NASA’s DART spacecraft and a Falcon 9 second stage booster that launched it can be seen as two small dots at the center of this image capture a few hours after the mission’s launch. (Image credit: The Virtual Telescope Project)

The robotic Elena telescope automatically tracked DART and the booster, both of which are visible at the center of the image as bright dots. The short white lines surrounding those two dots are stars in the background. When the image was taken, DART was about 93,000 miles (150,000 kilometers) from Earth, about half the distance between our planet and the moon, Masi said. 

In addition to the static image, the telescope also captured a short video sequence, which shows the separated second-stage booster blinking. This blinking, Masi said, is caused by the booster spinning. 

The pioneering DART mission will conduct a first-of-its-kind test that will show if and how a spacecraft can change the path of an asteroid by smashing into it. In September of next year, the spacecraft will ram into a 525-foot-wide (160 meters) asteroid “moonlet” known as Dimorphos, which orbits the larger space rock Didymos. The goal of the experiment is to alter Dimorphos’ orbit around Didymos, shortening it by several minutes, to prove that such an intervention could divert the trajectory of a large asteroid if, in the future, one were to be on a path that threatened planet Earth.

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DART also carries a small cubesat called LICIACube, from Italy’s space agency, which will be released 10 days ahead of DART’s self-destructive impact and film the aftermath of the crash. 

In 2024, the European Space Agency (ESA) will also send a larger surveyor spacecraft called Hera to the asteroid system that will analyze the crater and gather data about Didymos’ and Dimorphos’ physical structure and chemical composition. By then, astronomers will have known whether DART deflected Dimorphos, thanks to ground-based observations. 

Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook

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