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James Webb Space Telescope recovers from 2nd instrument glitch

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NASA’s powerful $10 billion space telescope is firing on all cylinders again.

The James Webb Space Telescope (JWST or Webb) returned to full science operations on Monday (Jan. 30), recovering from a glitch that affected one of its instruments.

The Webb team conducted days of testing and evaluation after a “communications delay” on Jan. 15 caused issues with the telescope’s Near Infrared Imager and Slitless Spectrograph (NIRISS) instrument, according to a Tuesday (Jan. 31) statement (opens in new tab) from NASA.

“Observations that were impacted by the pause in NIRISS operations will be rescheduled,” said the agency in its brief statement, noting the instrument was recovered successfully on Friday (Jan. 27).

Related: James Webb Space Telescope’s best images of all time (gallery)

NIRISS was provided by the Canadian Space Agency (CSA), so personnel from NASA and the CSA worked alongside one another for troubleshooting. The initial issue was a “communications delay within the instrument, causing its flight software to time out,” according to a Jan. 24 statement (opens in new tab) from NASA.

NIRISS can normally work in four different modes (opens in new tab), according to NASA. The instrument may be tasked with working as a camera when other JWST instruments are busy. Alternatively, NIRISS can look at light signatures of small exoplanet atmospheres, do high-contrast imaging or examine distant galaxies.

Prior to the NIRISS glitch, an issue arose on another Webb instrument in August 2022: a grating wheel inside the observatory’s Mid-Infrared Instrument (MIRI). The wheel is required for just one of MIRI’s four observing modes, however, so the instrument continued observing during recovery operations. Work on recovering the affected mode, called the Medium Resolution Spectrometer, was completed in November.

In December, the JWST team also spent two weeks dealing with a glitch that kept putting the telescope into safe mode, making science observations difficult. A software glitch in the observatory’s attitude control system was pinpointed as the issue, affecting the direction in which the telescope points. The observatory bounced back relatively quickly from that problem, resuming full science operations on Dec. 20.

Elizabeth Howell is the co-author of “Why Am I Taller (opens in new tab)?” (ECW Press, 2022; with Canadian astronaut Dave Williams), a book about space medicine. Follow her on Twitter @howellspace (opens in new tab). Follow us on Twitter @Spacedotcom (opens in new tab) or Facebook (opens in new tab).



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Venus-bound NASA instrument prepping to brave harsh atmosphere

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NASA scientists are preparing to paint the most detailed picture to date of the atmosphere of Venus when the aptly named DAVINCI — or Deep Atmosphere Venus Investigation of Noble Gases, Chemistry, and Imaging — mission drops a probe to the planet’s surface.

When the 3-foot-wide (0.9 meters) descent sphere of the DAVINCI mission takes its one-way parachute trip to Venus‘ surface in the early 2030s, it will be carrying the VASI (Venus Atmospheric Structure Investigation) instrument along with five other instruments. VASI will collect data regarding the temperature, pressure and winds of Venus’ atmosphere as it makes its hellish descent and enters the planet’s crushing lower atmosphere. 

“There are actually some big puzzles about the deep atmosphere of Venus,” Ralph Lorenz, the science lead for the VASI instrument and a planetary scientist at the Johns Hopkins Applied Physics Laboratory (APL) in Maryland, said in a statement. “We don’t have all the pieces of that puzzle and DAVINCI will give us those pieces by measuring the composition at the same time as the pressure and temperature as we get near the surface.”

Related: NASA’s Parker Solar Probe captures stunning Venus photo during close flyby

The dense atmosphere of Venus hides several mysteries, including how it is structured, as well as how the planet’s many volcanoes have interacted with it over the eons. One of scientists’ key goals in plunging a probe through the atmosphere of the second planet from the sun is to determine whether that world is still volcanically active. The probe could sniff this out through measurements of atmospheric temperatures, winds and composition.

Solving these puzzles could give scientists an idea of what continued volcanic activity could mean for our own planet’s atmosphere.

“The long-term habitability of our planet, as we understand it, rests on the coupling of the interior and atmosphere,” Lorenz said. “The long-term abundance of carbon dioxide in our atmosphere, which we really rely on to have kept Earth’s surface warm enough to be habitable over geologic time, relies on volcanoes.”

A one-way trip to Venus 

One of the main challenges associated with investigating Venus has been the extreme conditions of the planet, which boasts surface pressures up to 90 times greater than that of Earth and surface temperatures around 900 degrees Fahrenheit (460 degrees Celsius). 

Additionally, before any probe can reach the planet’s surface from orbit it must first pass through clouds of sulfuric acid in the upper atmosphere of Venus. (These clouds also happen to make Venus tough to observe from Earth; reflective and shiny, they obscure our view of the planet’s surface.)

These threats mean that DAVINCI’s descent sphere systems and sensors will be enclosed within a hardy, submarine-like structure. But while the sphere is built to withstand intense atmospheric pressures and is insulated to shield sensors from the intense heat near Venus’ surface, VASI’s sensors must be somewhat exposed to the harsh conditions in order to do their job.

“Venus is hard. The conditions, especially low in the atmosphere, make it very challenging to engineer the instrumentation and the systems to support the instrumentation,” Lorenz said. “All that has to be either protected from the environment or somehow built to tolerate it.”

As the sphere drops through the atmosphere of Venus, VASI will measure the temperature with a sensor within a thin, straw-like metal tube. As the atmosphere heats the tube, the sensor measures and records the expansion and thus the temperature without directly being exposed to the corrosive environment.

VASI will collect atmospheric pressure readings using a silicon membrane encased within it. One side of the membrane is exposed to a vacuum while the other side faces Venus’ atmosphere. The atmosphere pushes on the membrane, stretching it, and the extent of this stretching reveals the strength of the atmospheric pressure. 

The instrument will measure Venusian winds with a combination of accelerometers that test for changes in speed and direction and gyroscopes that measure orientation. The mission will also track changes in wind speed and direction by monitoring shifts in the frequency and wavelength of radio waves.

Named for Italian Renaissance polymath Leonardo da Vinci, DAVINCI is currently set for launch in 2029. If it stays on schedule, the descent sphere will plunge through the thick atmosphere of Venus in 2031.

The drop will take around an hour. The probe is not expected to survive the fall, but if it does, NASA scientists are prepared to get around 17 minutes of bonus science at the surface with the doomed device. 

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New NASA instrument detects methane ‘super-emitters’ from space | Climate News

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The Earth Surface Mineral Dust Source Investigation (EMIT) identified more than 50 methane hotspots around the world.

NASA scientists, using a tool designed to study how dust affects climate, have identified more than 50 methane-emitting hotspots around the world, a development that could help combat the potent greenhouse gas.

NASA said on Tuesday that its Earth Surface Mineral Dust Source Investigation (EMIT) had identified more than 50 methane “super-emitters” in Central Asia, the Middle East and the southwestern United States since it was installed in July onboard the International Space Station.

The newly measured methane hotspots — some previously known and others just discovered — include sprawling oil and gas facilities and large landfill sites. Methane is responsible for roughly 30 percent of the global rise in temperatures to date.

“Reining in methane emissions is key to limiting global warming,” NASA Administrator Bill Nelson said in a statement, adding that the instrument will help “pinpoint” methane super-emitters so that such emissions can be stopped “at the source”.

Circling Earth every 90 minutes from its perch onboard the space station some 400km (250 miles) high, EMIT is able to scan vast tracts of the planet dozens of kilometres across while also focusing in on areas as small as a football field.

The instrument, called an imaging spectrometer, was built primarily to identify the mineral composition of dust blown into Earth’s atmosphere from deserts and other arid regions, but it has proven adept at detecting large methane emissions.

“Some of the [methane] plumes EMIT detected are among the largest ever seen — unlike anything that has ever been observed from space,” said Andrew Thorpe, a Jet Propulsion Laboratory (JPL) research technologist leading the methane studies.

Examples of the newly-imaged methane super-emitters showcased by JPL on Tuesday included a cluster of 12 plumes from oil and gas infrastructure in Turkmenistan, some plumes stretching more than 32 km (20 miles).

Scientists estimate the Turkmenistan plumes collectively spew methane at a rate of 50,400kg (111,000 pounds) per hour, rivalling the peak flow from the 2015 Aliso Canyon gas field blowout near Los Angeles that ranks as one of the largest accidental methane releases in US history.

Two other large emitters were an oilfield in New Mexico and a waste-processing complex in Iran, emitting nearly 29,000kg (60,000 pounds) of methane per hour combined. The methane plume south of the Iranian capital Tehran was at least 4.8km (3 miles) long.

JPL officials said neither site were previously known to scientists.

“As it continues to survey the planet, EMIT will observe places in which no one thought to look for greenhouse-gas emitters before, and it will find plumes that no one expects,” Robert Green, EMIT’s principal investigator at JPL, said in a statement.

A by-product of decomposing organic material and the chief component of natural gas used in power plants, methane accounts for a fraction of all human-caused greenhouse emissions but has about 80 times more heat-trapping capacity pound-for-pound than carbon dioxide.

Compared with CO2, which lingers in the atmosphere for centuries, methane persists for only about a decade, meaning that reductions in methane emissions have a more immediate effect on planetary warming.



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Nasa’s Moxie instrument successfully makes oxygen on Mars | Mars

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An instrument the size of a lunchbox has been successfully generating breathable oxygen on Mars, doing the work of a small tree.

Since February last year the Mars oxygen in-situ resource utilisation experiment, or Moxie, has been successfully making oxygen from the red planet’s carbon dioxide-rich atmosphere.

Researchers suggest a scaled-up version of Moxie could be sent to Mars, to continuously produce oxygen at the rate of several hundred trees, ahead of humans going to the planet.

Moxie touched down on the Martian surface as part of Nasa’s Perseverance rover mission.

In a study researchers report that by the end of 2021 Moxie was able to produce oxygen on seven experimental runs, in a variety of atmospheric conditions, including during the day and night, and through different Martian seasons.

In each run it reached its goal of producing 6g of oxygen per hour – similar to the rate of a modest tree on Earth.

It is hoped that at full capacity the system could generate enough oxygen to sustain humans once they arrive on Mars, and fuel a rocket to return humans to Earth.

Moxie deputy principal investigator Jeffrey Hoffman, a professor of the practice in Massachusetts Institute of Technology’s (MIT) Department of Aeronautics and Astronautics, said: “This is the first demonstration of actually using resources on the surface of another planetary body, and transforming them chemically into something that would be useful for a human mission.”

The current version of the instrument is small by design in order to fit aboard the Perseverance rover, and is built to run for short periods. A full-scale oxygen factory would include larger units that would ideally run continuously.

So far, Moxie has shown that it can make oxygen at almost any time of the Martian day and year.

Michael Hecht, principal investigator of the Moxie mission at MIT’s Haystack Observatory, said: “The only thing we have not demonstrated is running at dawn or dusk, when the temperature is changing substantially.

“We do have an ace up our sleeve that will let us do that, and once we test that in the lab, we can reach that last milestone to show we can really run any time.”

If the system can operate successfully despite repeatedly turning on and off, this would suggest a full-scale system, designed to run continuously, could do so for thousands of hours.

Hoffman said: “To support a human mission to Mars, we have to bring a lot of stuff from Earth, like computers, spacesuits, and habitats.

“But dumb old oxygen? If you can make it there, go for it – you’re way ahead of the game.”

The findings are published in the journal Science Advances.

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This Stunning Image Shows a Star Like You Have Never Seen One Before

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It looks a bit like neon artwork from the ’80s. But what the image above really shows is much, much cooler.

It’s a star, and the first light image captured by the newest instrument on the Gemini South telescope, the Gemini High-resolution Optical SpecTrograph, or GHOST. What it shows is the entire optical spectrum of light emitted by a star named HD 222925, in amazing resolution.

 

“This is an exciting milestone for astronomers around the globe who rely on Gemini South to study the Universe from this exceptional vantage point in Chile,” said Jennifer Lotz, director of Gemini Observatory.

“Once this next-generation instrument is commissioned, GHOST will be an essential component of the astronomer’s toolbox.”

The light we can actually see being emitted by stars is chock full of hidden details describing the distant sun’s features. It can show us whether a star is moving by how light shifts from one end of the spectrum to the other, while variations in brightness can reveal internal oscillations, which can be analyzed by asteroseismologists.

The entire spectrum of the star also reveals what it’s made of, which in turn can be used to learn all sorts of things about it, such as how old the star is, and where it formed.

That’s because different elements absorb and re-emit light differently. When astronomers look at a star’s spectrum, they can look for brighter and dimmer wavelengths, and use that information to determine which elements are present in the star’s atmosphere.

You can see what the dimmer features, known as absorption lines, look like in the image below.

The labeled spectrum of HD 222925. (International Gemini Observatory/NOIRLab/NSF/AURA/GHOST Consortium)

This technique was recently used on Hubble observations HD 222925, a really oddball star located around 1,460 light-years away. Spectral analysis revealed the most elements ever seen in a star’s atmosphere, a whopping 65 – most of which were heavy elements that can only form in extremely energetic events, such as a neutron star collision or supernova.

That means that HD 222925, which is in a very late stage at the end of its life, probably formed from a cloud that was rich in these elements in the first place, seeded by the deaths of stars that had come before it.

 

The new images from GHOST have not revealed anything new about the star – yet. The star was the target of the instrument’s ‘first light’, the first image taken by a new telescope to check the telescope is working, and how well. This allows scientists to make any necessary first adjustments to the instrument.

The commissioning phase comes next, in which scientists and technicians will put GHOST through its paces to make sure the instrument is performing as intended.

Once that stage is complete, and any further adjustments made, GHOST will be ready for scientific observation, probably around the first half of next year.

That will be something to look forward to. GHOST, which took 10 years to construct, is 10 times more powerful than Gemini’s other major optical spectrograph, GMOS. It is, scientists say, the most powerful and sensitive spectrograph of its kind currently in operation on comparable telescopes.

It’s expected that GHOST will be able to provide fascinating insights on stars identified as interesting targets by other telescopes and surveys, and deliver us many more stars, split into their constituent wavelengths – beautiful ‘star-bows’ that will hopefully unlock many hidden secrets of the Milky Way.

The images were published by NOIRLab’s International Gemini Observatory here.

 

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Another Primary Webb Space Telescope Instrument Gets the “Go for Science”

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This illustration shows the cold side of the Webb telescope, where the mirrors and instruments are positioned. Credit: Northrop Grumman

Recently, NIRISS, one of

“We are thrilled that MIRI is now a functioning, state-of-the-art instrument with performances across all its capabilities better than expected.” — Gillian Wright and George Rieke

MIRI’s coronagraphic imaging capability, which uses two different styles of masks to intentionally block starlight from hitting its sensors when attempting to make observations of the star’s orbiting planets, was the last MIRI mode to be checked off. These customized masks allow scientists to directly detect exoplanets and study dust disks around their host stars in a way that has never been done before.

Along with Webb’s three other instruments, MIRI initially cooled off in the shade of Webb’s tennis-court-size sunshield to about 90 kelvins (minus 298 degrees

Webb 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

“We are thrilled that MIRI is now a functioning, state-of-the-art instrument with performances across all its capabilities better than expected. Our multinational commissioning team has done a fantastic job getting MIRI ready in the space of just a few weeks. Now we celebrate all the people, scientists, engineers, managers, national agencies, European Space Agency (ESA), and NASA, who have made this instrument a reality as MIRI begins to explore the infrared universe in ways and to depths never achieved before,” said Gillian Wright, MIRI European principal investigator at the UK Astronomy Technology Center, and George Rieke, MIRI science lead at the University of Arizona. MIRI was developed as a partnership between NASA and ESA (European Space Agency), with NASA’s Jet Propulsion Laboratory leading the U.S. efforts and a multi-national consortium of European astronomical institutes contributing for ESA.

With NIRISS and MIRI postlaunch commissioning activities concluded, the Webb team will continue to focus on checking off the remaining two modes on its other instruments. NASA’s James Webb Space Telescope, a partnership with ESA (European Space Agency) and CSA, will release its first full-color images and spectroscopic data on July 12, 2022.