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Forest degradation primary driver of carbon loss in the Brazilian Amazon
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By European Space Agency
New research, partially funded by ESA, reveals that the cool ‘ocean skin’ allows oceans to absorb more atmospheric carbon dioxide than previously thought. These findings could enhance global carbon assessments, shaping more effective emission-reduction policies.
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By NASA
A NASA-developed material made of carbon nanotubes will enable our search for exoplanets—some of which might be capable of supporting life. Originally developed in 2007 by a team of researchers led by Innovators of the Year John Hagopian and Stephanie Getty at NASA’s Goddard Space Flight Center, this carbon nanotube technology is being refined for potential use on NASA’s upcoming Habitable Worlds Observatory (HWO)—the first telescope designed specifically to search for signs of life on planets orbiting other stars.
As shown in the figure below, carbon nanotubes look like graphene (a single layer of carbon atoms arranged in a hexagonal lattice) that is rolled into a tube. The super-dark material consists of multiwalled carbon nanotubes (i.e., nested nanotubes) that grow vertically into a “forest.” The carbon nanotubes are 99% empty space so the light entering the material doesn’t get reflected. Instead, the light enters the nanotube forest and jiggles electrons in the hexagonal lattice of carbon atoms, converting the light to heat. The ability of the carbon nanotubes to eliminate almost all light is enabling for NASA’s scientific instruments because stray light limits how sensitive the observations can be. When applied to instrument structures, this material can eliminate much of the stray light and enable new and better observations.
Left: Artist’s conception of graphene, single and multiwalled carbon nanotube structures. Right: Scanning electron microscope image of vertically aligned multiwalled carbon nanotube forest with a section removed in the center. Credit: Delft University/Dr. Sten Vollebregt and NASA GSFC Viewing exoplanets is incredibly difficult; the exoplanets revolve around stars that are 10 billion times brighter than they are. It’s like looking at the Sun and trying to see a dim star next to it in the daytime. Specialized instruments called coronagraphs must be used to block the light from the star to enable these exoplanets to be viewed. The carbon nanotube material is employed in the coronagraph to block as much stray light as possible from entering the instrument’s detector.
The image below depicts a notional telescope and coronagraph imaging an exoplanet. The telescope collects the light from the distant star and exoplanet. The light is then directed to a coronagraph that collimates the beam, making the light rays parallel, and then the beam is reflected off the apodizer mirror, which is used to precisely control the diffraction of light. Carbon nanotubes on the apodizer mirror absorb the stray light that is diffracted off edges of the telescope structures, so it does not contaminate the observations. The light is then focused on the focal plane mask, which blocks the light from the star but allows light from the exoplanet to pass. The light gets collimated again and is then reflected off a deformable mirror to correct distortion in the image. Finally, the light passes through the Lyot Stop, which is also coated with carbon nanotubes to remove the remaining stray light. The beam is then focused onto the detector array, which forms the image.
Even with all these measures some stray light still reaches the detector, but the coronagraph creates a dark zone where only the light coming from the exoplanet can be seen. The final image on the right in the figure below shows the remaining light from the star in yellow and the light from the exoplanet in red in the dark zone.
Schematic of a notional telescope and coronagraph imaging an exoplanet Credit: Advanced Nanophotonics/John Hagopian, LLC HWO will use a similar scheme to search for habitable exoplanets. Scientists will analyze the spectrum of light captured by HWO to determine the gases in the atmosphere of the exoplanet. The presence of water vapor, oxygen, and perhaps other gases can indicate if an exoplanet could potentially support life.
But how do you make a carbon-nanotube-coated apodizer mirror that could be used on the HWO? Hagopian’s company Advanced Nanophotonics, LLC received Small Business Innovation Research (SBIR) funding to address this challenge.
Carbon nanotubes are grown by depositing catalyst seeds onto a substrate and then placing the substrate into a tube-shaped furnace and heating it to 1382 degrees F, which is red hot! Gases containing carbon are then flowed into the heated tube, and at these temperatures the gases are absorbed by the metal catalyst and transform into a solution, similar to how carbon dioxide in soda water fizzes. The carbon nanotubes literally grow out of the substrate into vertically aligned tubes to form a “forest” wherever the catalyst is located.
Since the growth of carbon nanotubes on the apodizer mirror must occur only in designated areas where stray light is predicted, the catalyst must be applied only to those areas. The four main challenges that had to be overcome to develop this process were: 1) how to pattern the catalyst precisely, 2) how to get a mirror to survive high temperatures without distorting, 3) how to get a coating to survive high temperatures and still be shiny, and 4) how to get the carbon nanotubes to grow on top of a shiny coating. The Advanced Nanophotonics team refined a multi-step process (see figure below) to address these challenges.
Making an Apodizer Mirror for use in a coronagraph Credit: Advanced Nanophotonics/John Hagopian, LLC First a silicon mirror substrate is fabricated to serve as the base for the mirror. This material has properties that allow it to survive very high temperatures and remain flat. These 2-inch mirrors are so flat that if one was scaled to the diameter of Earth, the highest mountain would only be 2.5 inches tall!
Next, the mirror is coated with multiple layers of dielectric and metal, which are deposited by knocking atoms off a target and onto the mirror in a process called sputtering. This coating must be reflective to direct the desired photons, but still be able to survive in the hot environment with corrosive gases that is required to grow carbon nanotubes.
Then a material called resist that is sensitive to light is applied to the mirror and a pattern is created in the resist with a laser. The image on the mirror is chemically developed to remove the resist only in the areas illuminated by the laser, creating a pattern where the mirror’s reflecting surface is exposed only where nanotube growth is desired.
The catalyst is then deposited over the entire mirror surface using sputtering to provide the seeds for carbon nanotube growth. A process called liftoff is used to remove the catalyst and the resist that are located where nanotubes growth is not needed. The mirror is then put in a tube furnace and heated to 1380 degrees Fahrenheit while argon, hydrogen, and ethylene gases are flowed through the tube, which allows the chemical vapor deposition of carbon nanotubes where the catalyst has been patterned. The apodizer mirror is cooled and removed from the tube furnace and characterized to make sure it is still flat, reflective where desired, and very black everywhere else.
The Habitable Worlds Observatory will need a coronagraph with an optimized apodizer mirror to effectively view exoplanets and gather their light for evaluation. To make sure NASA has the best chance to succeed in this search for life, the mirror design and nanotube technology are being refined in test beds across the country.
Under the SBIR program, Advanced Nanophotonics, LLC has delivered apodizers and other coronagraph components to researchers including Remi Soummer at the Space Telescope Science Institute, Eduardo Bendek and Rus Belikov at NASA Ames, Tyler Groff at NASA Goddard, and Arielle Bertrou-Cantou and Dmitri Mawet at the California Institute of Technology. These researchers are testing these components and the results of these studies will inform new designs to eventually enable the goal of a telescope with a contrast ratio of 10 billion to 1.
Reflective Apodizers delivered to Scientists across the country Credit: Advanced Nanophotonics/John Hagopian, LLC In addition, although the desired contrast ratio cannot be achieved using telescopes on Earth, testing apodizer mirror designs on ground-based telescopes not only facilitates technology development, but helps determine the objects HWO might observe. Using funding from the SBIR program, Advanced Nanophotonics also developed transmissive apodizers for the University of Notre Dame to employ on another instrument—the Gemini Planet Imager (GPI) Upgrade. In this case the carbon nanotubes were patterned and grown on glass that transmits the light from the telescope into the coronagraph. The Gemini telescope is an 8.1-meter telescope located in Chile, high atop a mountain in thin air to allow for better viewing. Dr. Jeffrey Chilcote is leading the effort to upgrade the GPI and install the carbon nanotube patterned apodizers and Lyot Stops in the coronagraph to allow viewing of exoplanets starting next year. Discoveries enabled by GPI may also drive future apodizer designs.
More recently, the company was awarded a Phase II SBIR contract to develop next-generation apodizers and other carbon nanotube-based components for the test beds of existing collaborators and new partners at the University of Arizona and the University of California Santa Clara.
Tyler Groff (left) and John Hagopian (right) display a carbon nanotube patterned apodizer mirror used in the NASA Goddard Space Flight Center coronagraph test bed. Credit: Advanced Nanophotonics/John Hagopian, LLC As a result of this SBIR-funded technology effort, Advanced Nanophotonics has collaborated with NASA Scientists to develop a variety of other applications for this nanotube technology.
A special carbon nanotube coating developed by Advanced Nanophotonics was used on the recently launched NASA Ocean Color Instrument onboard the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission that is observing both the atmosphere and phytoplankton in the ocean, which are key to the health of our planet. A carbon nanotube coating that is only a quarter of the thickness of a human hair was applied around the entrance slit of the instrument. This coating absorbs 99.5% of light in the visible to infrared and prevents stray light from reflecting into the instrument to enable more accurate measurements. Hagopian’s team is also collaborating with the Laser Interferometer Space Antenna (LISA) team to apply the technology to mitigate stray light in the European Space Agency’s space-based gravity wave mission.
They are also working to develop carbon nanotubes for use as electron beam emitters for a project sponsored by the NASA Planetary Instrument Concepts for the Advancement of Solar System Observations (PICASSO) Program. Led by Lucy Lim at NASA Goddard, this project aims to develop an instrument to probe asteroid and comet constituents in space.
In addition, Advanced Nanophotonics worked with researcher Larry Hess at NASA Goddard’s Detector Systems Branch and Jing Li at the NASA Ames Research Center to develop a breathalyzer to screen for Covid-19 using carbon nanotube technology. The electron mobility in a carbon nanotube network enables high sensitivity to gases in exhaled breath that are associated with disease.
This carbon nanotube-based technology is paying dividends both in space, as we continue our search for life, and here on Earth.
For additional details, see the entry for this project on NASA TechPort.
PROJECT LEAD
John Hagopian (Advanced Nanophotonics, LLC)
SPONSORING ORGANIZATION
SMD-funded SBIR project
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Last Updated Sep 03, 2024 Related Terms
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An astronaut aboard the International Space Station photographed wildfire smoke from Nova Scotia billowing over the Atlantic Ocean in May 2023. Warm weather and lack of rain fueled blazes across Canada last year, burning 5% of the country’s forests.NASA Extreme wildfires like these will continue to have a large impact on global climate.
Stoked by Canada’s warmest and driest conditions in decades, extreme forest fires in 2023 released about 640 million metric tons of carbon, NASA scientists have found. That’s comparable in magnitude to the annual fossil fuel emissions of a large industrialized nation. NASA funded the study as part of its ongoing mission to understand our changing planet.
The research team used satellite observations and advanced computing to quantify the carbon emissions of the fires, which burned an area roughly the size of North Dakota from May to September 2023. The new study, published on Aug. 28 in the journal Nature, was led by scientists at NASA’s Jet Propulsion Laboratory in Southern California.
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Carbon monoxide from Canada wildfires curls thousands of miles across North America in this animation showing data from summer 2023. Lower concentrations are shown in purple; higher concentrations are in yellow. Red triangles indicate fire hotspots.NASA’s Goddard Space Flight Center They found that the Canadian fires released more carbon in five months than Russia or Japan emitted from fossil fuels in all of 2022 (about 480 million and 291 million metric tons, respectively). While the carbon dioxide (CO2) emitted from both wildfires and fossil fuel combustion cause extra warming immediately, there’s an important distinction, the scientists noted. As the forest regrows, the amount of carbon emitted from fires will be reabsorbed by Earth’s ecosystems. The CO2 emitted from the burning of fossil fuels is not readily offset by any natural processes.
An ESA (European Space Agency) instrument designed to measure air pollution observed the fire plumes over Canada. The TROPOspheric Monitoring Instrument, or TROPOMI, flies aboard the Sentinel 5P satellite, which has been orbiting Earth since 2017. TROPOMI has four spectrometers that measure and map trace gases and fine particles (aerosols) in the atmosphere.
The scientists started with the end result of the fires: the amount of carbon monoxide (CO) in the atmosphere during the fire season. Then they “back-calculated” how large the emissions must have been to produce that amount of CO. They were able to estimate how much CO2 was released based on ratios between the two gases in the fire plumes.
“What we found was that the fire emissions were bigger than anything in the record for Canada,” said Brendan Byrne, a JPL scientist and lead author of the new study. “We wanted to understand why.”
Warmest Conditions Since at Least 1980
Wildfire is essential to the health of forests, clearing undergrowth and brush and making way for new plant life. In recent decades, however, the number, severity, and overall size of wildfires have increased, according to the U.S. Department of Agriculture. Contributing factors include extended drought, past fire management strategies, invasive species, and the spread of residential communities into formerly less developed areas.
To explain why Canada’s fire season was so intense in 2023, the authors of the new study cited tinderbox conditions across its forests. Climate data revealed the warmest and driest fire season since at least 1980. Temperatures in the northwest part of the country — where 61% of fire emissions occurred — were more than 4.5 degrees Fahrenheit (2.6 degrees Celsius) above average from May through September. Precipitation was also more than 3 inches (8 centimeters) below average for much of the year.
Driven in large part by these conditions, many of the fires grew to enormous sizes. The fires were also unusually widespread, charring some 18 million hectares of forest from British Columbia in the west to Quebec and the Atlantic provinces in the east. The area of land that burned was more than eight times the 40-year average and accounted for 5% of Canadian forests.
“Some climate models project that the temperatures we experienced last year will become the norm by the 2050s,” Byrne said. “The warming, coupled with lack of moisture, is likely to trigger fire activity in the future.”
If events like the 2023 Canadian forest fires become more typical, they could impact global climate. That’s because Canada’s vast forests compose one of the planet’s important carbon sinks, meaning that they absorb more CO2 from the atmosphere than they release. The scientists said that it remains to be seen whether Canadian forests will continue to absorb carbon at a rapid rate or whether increasing fire activity could offset some of the uptake, diminishing the forests’ capacity to forestall climate warming.
News Media Contacts
Jane J. Lee / Andrew Wang
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0307 / 626-379-6874
jane.j.lee@jpl.nasa.gov / andrew.wang@jpl.nasa.gov
Written by Sally Younger
2024-113
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Last Updated Aug 28, 2024 Related Terms
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By NASA
This photo shows the Wide Field Instrument for NASA’s Nancy Grace Roman Space Telescope arriving at the big clean room at NASA’s Goddard Space Flight Center. About the size of a commercial refrigerator, this instrument will help astronomers explore the universe’s evolution and the characteristics of worlds outside our solar system. Unlocking these cosmic mysteries and more will offer a better understanding of the nature of the universe and our place within it.NASA/Chris Gunn The primary instrument for NASA’s Nancy Grace Roman Space Telescope is a sophisticated camera that will survey the cosmos from the outskirts of our solar system all the way out to the edge of the observable universe. Called the Wide Field Instrument, it was recently delivered to the agency’s Goddard Space Flight Center in Greenbelt, Maryland.
The camera’s large field of view, sharp resolution, and sensitivity from visible to near-infrared wavelengths will give Roman a deep, panoramic view of the universe. Scanning much larger portions of the sky than astronomers can with NASA’s Hubble or James Webb space telescopes will open new avenues of cosmic exploration. Roman is designed to study dark energy (a mysterious cosmic pressure thought to accelerate the universe’s expansion), dark matter (invisible matter seen only via its gravitational influence), and exoplanets (worlds beyond our solar system).
“This instrument will turn signals from space into a new understanding of how our universe works,” said Julie McEnery, the Roman senior project scientist at Goddard. “To achieve its main goals, the mission will precisely measure hundreds of millions of galaxies. That’s quite a dataset for all kinds of researchers to pull from, so there will be a flood of results on a vast array of science.”
Technicians inspect NASA’s Nancy Grace Roman Space Telescope’s Wide Field Instrument upon delivery to the big clean room at NASA’s Goddard Space Flight Center.NASA/Chris Gunn About 1,000 people contributed to the Wide Field Instrument’s development, from the initial design phase to assembling it from around a million individual components. The WFI’s design was a collaborative effort between Goddard and BAE Systems in Boulder, Colorado. Teledyne Imaging Sensors, Hawaii Aerospace Corporation, Applied Aerospace Structures Corporation, Northrop Grumman, Honeybee Robotics, CDA Intercorp, Alluxa, and JenOptik provided critical components. Those parts and many more, made by other vendors, were delivered to Goddard and BAE Systems, where they were assembled and tested prior to the instrument’s delivery to Goddard this month.
“I am so happy to be delivering this amazing instrument,” said Mary Walker, Roman’s Wide Field Instrument manager at Goddard. “All the years of hard work and the team’s dedication have brought us to this exciting moment.”
NASA’s Nancy Grace Roman Space Telescope is a next-generation observatory that will survey the infrared universe from beyond the orbit of the Moon. The spacecraft’s giant camera, the Wide Field Instrument, will be fundamental to this exploration. Data it gathers will enable scientists to discover new and uniquely detailed information about planetary systems around other stars. The instrument will also map how matter is structured and distributed throughout the cosmos, which could ultimately allow scientists to discover the fate of the universe. Watch this video to see a simplified version of how the Wide Field Instrument works.
NASA’s Goddard Space Flight Center Seeing the Bigger Picture
After Roman launches by May 2027, each of the Wide Field Instrument’s 300-million-pixel images will capture a patch of the sky bigger than the apparent size of a full moon. The instrument’s large field of view will enable sweeping celestial surveys, revealing billions of cosmic objects across vast stretches of time and space. Astronomers will conduct research that could take hundreds of years using other telescopes.
And by observing from space, Roman’s camera will be very sensitive to infrared light –– light with longer wavelengths than our eyes can see –– from far across the cosmos. This ancient cosmic light will help scientists address some of the biggest cosmic mysteries, one of which is how the universe evolved to its present state.
From the telescope, light’s path through the instrument begins by passing through one of several optical elements in a large wheel. These elements include filters, which allow specific wavelengths of light to pass through, and a grism and prism, which split light into all of its individual colors. These detailed patterns, called spectra, reveal information about the object that emitted the light.
Then, the light travels on toward the camera’s set of 18 detectors, which each contain 16 million pixels. The large number of detectors and pixels gives Roman its large field of view. The instrument is designed for accurate, stable images and exquisite precision in measuring the exact amount of light in every pixel of every image, giving Roman unprecedented power to study dark energy. The detectors will be held at about minus 300 degrees Fahrenheit (minus 184 degrees Celsius) to increase sensitivity to the infrared universe.
“When the light reaches the detectors, that marks the end of what may have been a 10-billion-year journey through space,” said Art Whipple, an aerospace engineer at Goddard who has contributed to the Wide Field Instrument’s design and construction for more than a decade.
Once Roman begins observing, its rapid data delivery will require new analysis techniques.
“If we had every astronomer on Earth working on Roman data, there still wouldn’t be nearly enough people to go through it all,” McEnery said. “We’re looking at modern techniques like machine learning and artificial intelligence to help sift through Roman’s observations and find where the most exciting things are.”
Now that the Wide Field Instrument is at Goddard, it will be tested to ensure everything is operating as expected. It will be integrated onto the instrument carrier and mated to the telescope this fall, bringing scientists one step closer to making groundbreaking discoveries for decades to come.
One panel on the Wide Field Instrument for NASA’s Nancy Grace Roman Space Telescope contains hundreds of names of team members who helped design and build the instrument.BAE Systems To virtually tour an interactive version of the telescope, visit:
https://roman.gsfc.nasa.gov/interactive
The Nancy Grace Roman Space Telescope is managed at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, with participation by NASA’s Jet Propulsion Laboratory and Caltech/IPAC in Southern California, the Space Telescope Science Institute in Baltimore, and a science team comprising scientists from various research institutions. The primary industrial partners are BAE Systems, Inc. in Boulder, Colorado; L3Harris Technologies in Rochester, New York; and Teledyne Scientific & Imaging in Thousand Oaks, California.
By Ashley Balzer
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Media contact:
Claire Andreoli
claire.andreoli@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
301-286-1940
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Last Updated Aug 13, 2024 EditorAshley BalzerContactAshley Balzerashley.m.balzer@nasa.govLocationGoddard Space Flight Center Related Terms
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NASA used its remotely piloted Ikhana aircraft to test technology it helped develop or recommended to the U.S. Forest Service, including a system to send sensor data to decision makers on the ground in near real time.Credit: NASA It’s not easy to predict the path of forest fires—a lot depends on constantly changing factors like wind. But it is crucial to be as accurate as possible because the lives, homes, and businesses of the tens of thousands of people living and working in fire-prone areas depend on the reliability of these predictions. Sensors mounted on airplanes or drones that provide a picture of the fire from above are an important tool, and that’s where NASA comes in.
In partnership with the U.S. Forest Service, local and state firefighting agencies, and the Bureau of Land Management, NASA plays a pivotal role in battling infernos. The agency’s extensive experience and technical expertise in remote sensing technology have significantly improved the speed and accuracy of information relayed to firefighting decision-makers.
According to Don Sullivan, who specialized in information technology design at the time, the Airborne Science Program at NASA’s Ames Research Center in Silicon Valley, California, was integral to that effort.
In the 1990s, NASA began a project to adapt uncrewed aircraft for environmental research. The researchers at Ames wanted to ensure the technology would be useful to the broadest possible spectrum of potential end users. One concept tested during the project was sending data in real-time to the ground via communications links installed on the aircraft.
That link sent data faster and to multiple recipients at once—not just the team on the fire front line, but also the commanders organizing the teams and decision makers looking at the big picture across the entire region throughout the fire season, explained Sullivan.
For the Forest Service, this was a much-needed upgrade to the original system on their crewed jets: rolling up a printout and later thumb drives with thermal sensor data placed into a plastic tube attached to a parachute and dropped out of the airplane. NASA’s remotely piloted aircraft called Ikhana tested the technology, and it’s still used by the agency to collect data on wildfires.
Since the introduction of this technology, wildfires have gotten bigger, burn hotter, and set new records every year. But in California in 2008, this technology helped fight what was then the worst fire season on record. A NASA test flight using a data downlink system provided updated information to the incident managers that was crucial in determining where to send firefighting resources and whether a full evacuation of the town of Paradise was needed.
Without that timely information, said Sullivan, “there likely would have been injuries and certainly property damage that was worse than it turned out to be.”
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