Category: Science-enabling Technology

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Digging Deeper to Find Life on Ocean Worlds

Source: NASA

In February 2023, researchers from around the country gathered at a NASA-sponsored workshop to discuss the latest developments and a roadmap for a cryobot mission concept to drill through the icy crusts of Europa and Enceladus and search for life.

“Follow the water” has been the mantra of the astrobiology community in search of alien life in the universe. Water is a fundamental building block of all terrestrial life as we know it and—as discovered by various space missions—water is abundant throughout the solar system, and perhaps, the universe. Ancient eroded features on Mars show clear evidence of a wet history, and the ongoing quest of the Perseverance rover aims to uncover clues as to whether or not Mars once hosted a population of microbes. However, there is only so much we can learn from the fossil record. To truly understand the nature of possible alien life, we must directly investigate the source—the liquid water.

Enter “Ocean Worlds.” Over the past two decades, scientists have discovered that a vast number of icy moons orbit the outer giant planets in our solar system. Many of these moons show strong evidence for harboring global oceans beneath their icy crusts.  In fact, these moons likely have far more liquid water than all of Earth’s oceans combined, and some may even have the right conditions to foster life. Two moons, in particular, have captured the imaginations of astrobiologists due to their amenable conditions for life and their relative ease of interrogation: Jupiter’s moon, Europa and Saturn’s moon, Enceladus. Both show strong evidence of a global subsurface ocean beneath a kilometers-thick water-ice crust—but how can we access this liquid water?

Various concepts for ocean access have been investigated over the past decades, ranging from robots that descend through crevasses to drills of varying types. One concept that has emerged as a leading candidate is the cryobot. A cryobot is a self-contained cylindrical probe that uses heat to melt the ice beneath it. The melted water then flows around the probe before refreezing behind it. Thermal ice drilling is so simple and effective that it has become a common tool for studying terrestrial glaciers and ice sheets. But how can we translate this technology to a system that can penetrate planetary icy crusts, which are colder, thicker, and more uncertain?

This dilemma has been a core focus of researchers—many of whom are supported by NASA’s Scientific Exploration Subsurface Access Mechanism for Europa (SESAME) and Concepts for Ocean worlds Life Detection Technology (COLDTech) programs—for the past several years. In February 2023, NASA’s Planetary Exploration Science Technology Office (PESTO) convened a workshop at the California Institute of Technology, which brought together nearly 40 top researchers from diverse fields and institutions around the country to discuss progress in maturing this technology and to assess the challenges that remain.  Recent studies have made significant progress in refining our understanding of the ice shell environment, detailing a mission architecture, and maturing critical subsystems and technologies. In particular, workshop participants identified four key subsystems that drive the roadmap for developing a flight-ready architecture: the power, thermal, mobility, and communication subsystems.

First, the heart of a cryobot is a nuclear power system that generates the sustained heat required to melt through kilometers of ice. Various nuclear power systems that could suit a cryobot system have been identified, including the familiar Radioisotope Power Systems (RPS) that have powered many deep-space missions, and fission reactors that may be developed in the coming years. Two key constraints that drive the power system design are: (1) sufficient total power and density to facilitate efficient melting (about 10 kW), and (2) integration within a structural vessel to protect the power system from the high pressures of the deep ocean. These challenges are both solvable and have some historical precedent: NASA’s Cassini mission had a 14 kW thermal power system, and several Radioisotope Thermoelectric Generators (RTGs) were deployed to the bottom of the ocean in the 1960s and 1970s as power sources for navigation beacons, which operated in comparable pressures to the Europan ocean. However, a cryobot power system will require a concerted effort and close collaboration with the Department of Energy throughout the maturation of the mission concept.

Second, a thermal management system is required to manage the heat produced by the onboard nuclear power system, maintain safe internal temperatures, and distribute heat to the environment for efficient performance. This system requires two independent pumped fluid circuits: one that circulates an internal working fluid through channels embedded in the skin and another that circulates melted ice water with the surounding environment. Some of these technologies have been demonstrated at reduced and full scale, but more work is needed to validate performance at the range of ice conditions expected in the outer solar system.

In addition, the icy shells of Europa and Enceladus will contain impurities such as dust and salt, which, when sufficiently concentrated, may require auxilliary systems to penetrate. A combination of “water jetting” and mechanical cutting has been demonstrated to be effective at clearing debris ranging from fine particulate to solid blocks of salt from beneath the probe. Some impurities such as larger rocks, voids, or water bodies may remain impenetrable, requiring the cryobot to incorporate a downward-looking mapping sensor and steering mechanism—both of which have been demonstrated in terrestrial prototypes, though not yet in an integrated system. High-priority future work includes a more rigorous and probabilistic definition of the icy environments to quantify the likelihood of potential mobility hazards, and an integrated demonstration of hazard mitigation systems on a flight-like cryobot system. Europa Clipper will also provide key observations to constrain the prevalence and characteristics of hazards for a cryobot.

Finally, a cryobot mission requires a robust and redundant communication link through the ice shell to enable the lander to relay data to an orbiting relay asset or directly to Earth. Fiber optic cables are the industry standard for communicating with terrestrial melt probes and deep-sea vehicles, but require careful validation for deployment through ice shells, which are active. The movement of ice in these shells could break the cable. A team led by Dr. Kate Craft at the Johns Hopkins Applied Physics Laboratory has been investigating the propensity of tethers embedded in ice to break during ice-shear events, as well as methods to mitigate such breakage. While preliminary results from this study are highly encouraging, other teams are exploring wireless techniques for communicating through the ice, including radio frequency, acoustic, and magnetic transceivers.  These communication systems must be integrated onto the aft end of the probe and depoyed during its descent. Current projects funded under the NASA COLDTech program are taking the first steps toward addressing key risks for the communications system. Future work must validate performance across a broader range of conditions and demonstrate integration on a cryobot.

While the power, thermal, mobility, and communication subsystems took center stage, workshop participants also discussed other key systems and technologies that will require maturation to enable a cryobot mission. These topics include an integrated instrument suite with accommodations for liquid sampling and outward-facing apertures, planetary protection and sterilization strategies, materials selection for corrosion mitigation, ice-anchoring mechanisms, and autonomy. However, none of these technologies were identified as major risks or challenges in the cryobot mission concept roadmap.

Overall, the consensus finding of workshop participants was that this mission concept remains feasible, scientifically compelling, and the most plausible near-term way to directly search for life in situ on an ocean world. Continued support would allow scientists and engineers to make even further progress toward readying cryobots for future mission opportunities. The potential for the direct detection of life on another world seems more possible than ever.

This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).

Dr. Benjamin Hockman, Jet Propulsion Laboratory, California Institute of Technology

NASA’s Planetary Exploration Science Technology Office (PESTO)

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Deformable Mirrors in Space: Key Technology toDirectly Image Earth Twins

Source: NASA

Deformable Mirror Technology development

Deformable mirrors enable direct imaging of exoplanets by correcting imperfections or shape changes in a space telescope down to subatomic scales.

Finding and studying Earth-like planets orbiting nearby stars is critical to understand whether we are alone in the universe. To study such planets and assess if they can sustain life, it is necessary to directly image them. However, these planets are difficult to observe, since light from the host star hides them with its glare. A coronagraph instrument can be used to remove the glare light from the host star, enabling reflected light from the planet to be collected.  A deformable mirror is an essential component of a coronagraph, as it can correct the tiniest of imperfections in the telescope and remove any remaining starlight contamination.

Detecting an Earth-like planet poses significant challenges as the planet is approximately 10 billion times fainter than its parent star. The main challenge is to block nearly all of the star’s light so that the faint light reflected from the planet can be collected.  A coronagraph can block the starlight, however, any instability in the telescope’s optics—such as misalignment between mirrors or a change in the mirror’s shape—can result in starlight leakage, causing glare that hides the planet. Therefore, detecting an Earth-like planet using a coronagraph requires precise control of both the telescope and the instrument’s optical quality, or wavefront, to an extraordinary level of 10s of picometers (pm), which is approximately on the order of the size of a hydrogen atom.

Deformable mirrors will enable future space coronagraphs to achieve this level of control. These devices will be demonstrated in space on a coronagraph technology demonstration instrument on NASA’s Roman Space Telescope, which will launch by May 2027. This technology will also be critical to enable a future flagship mission after Roman recommended by the 2020 Decadal Survey in Astronomy and Astrophysics, provisionally called the “Habitable Worlds Observatory” (HWO). 

What is a deformable mirror and how do they work?

Deformable Mirrors (DM) are devices that can adjust the optical path of incoming light by changing the shape of a reflective mirror using precisely controlled piston-like actuators. By adjusting the shape of the mirror, it is possible to correct the wavefront that is perturbated by optical aberrations upstream and downstream of the DM. These aberrations can be caused by external perturbations, like atmospheric turbulence, or by optical misalignments or defects internal to the telescope.

DM technology originated to enable adaptive optics (AO) in ground-based telescopes, where the primary goal is to correct the aberrations caused by atmospheric turbulence. The main characteristics of a DM are: 1) the number of actuators, which is proportional to the correctable field of view; 2) the actuators’ maximum stroke – i.e., how far they can move; 3) the DM speed, or time required to modify the DM surface; 4) the surface height resolution that defines the smallest wavefront control step, and (5) the stability of the DM surface.

Ground-based deformable mirrors have set the state-of-the-art in performance, but to lay the groundwork to eventually achieve ambitious goals like the Habitable Worlds Observatory, further development of DMs for use in space is underway.

For a space telescope, DMs do not need to correct for the atmosphere, but instead must correct the very small optical perturbations that slowly occur as the space telescope and instrument heat up and cool down in orbit. Contrast goals (the brightness difference between the planet and the star) for DMs in space are on the order of 10-10 which is 1000 times deeper than the contrast goals of ground-based counterparts. For space applications total stroke requirements are usually less than a micrometer; however, DM surface height resolution of ~10 pm and DM surface stability of ~10 pm/hour are the key and driving requirements.

Another key aspect is the increased number of actuators needed for both space- and ground-based applications.  Each actuator requires a high voltage connection (on the order of 100V) and fabricating a large number of connections creates an additional challenge.

Deformable Mirror State-of-the-Art

Two main DM actuator technologies are currently being considered for space missions. The first is electrostrictive technology, in which an actuator is mechanically connected to the DM’s reflective surface. When a voltage is applied to the actuator, it contracts and modifies the mirror surface. The second technology is the electrostatically-forced Micro Electro-Mechanical System (MEMS) DM. In this case, the mirror surface is deformed by an electrostatic force between an electrode and the mirror.

Several NASA-sponsored contractor teams are working on advancing the DM performance required to meet the requirements of future NASA missions, which are much more stringent than most commercial applications, and thus, have a limited market application. Some examples of those efforts include improving the mirror’s surface quality or developing more advanced DM electronics.

MEMS DMs manufactured by Boston Micromachines Corporation (BMC) have been tested in vacuum conditions and have undergone launch vibration testing. The largest space-qualified BMC device is the 2k DM (shown in Fig. 2), which has 50 actuators across its diameter (2040 actuators in total). Each actuator is only 400 microns across. The largest MEMS DM produced by BMC is the 4k DM, which has 64 actuators across its diameter (4096 actuators in total) and is used in the coronagraph instrument for the Gemini ground-based observatory. However, the 4k DM has not been qualified for space flight.

Electrostrictive DMs manufactured by AOA Xinetics (AOX) have also been validated in vacuum and qualified for space flight. The AOX 2k DM has a 48 x 48 actuator grid (2304 actuators) with a 1 mm pitch. Two of these AOX 2k DMs will be used in the Roman Space Telescope Coronagraph (Fig. 3) to demonstrate the DM technology for high-contrast imaging in space. AOX has also manufactured larger devices, including a 64 x 64 actuator unit tested at JPL.

Preparing the technology for the Habitable Worlds Observatory

The HWO would also involve unprecedented wavefront control requirements, such as a resolution step size down to single-digit picometers, and a stability of ~10 pm/hr. These requirements will not only drive the DM design, but also the electronics that control the DMs, since the resolution and stability are largely defined by the command signals sent by the controller, which require the implementation of filters to remove any noise the electronics could introduce.

NASA’s Astrophysics Division investments in DM technologies have advanced DMs for space flight onboard the Roman Space Telescope Coronagraph, and the Division is preparing a Technology Roadmap to further advance the DM performance to enable the HWO.

Author: Eduardo Bendek, Ph.D. Jet Propulsion Laboratory, California Institute of Technology.

The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).

Dr. Eduardo Bendek (JPL) and Dr. Tyler Groff (GSFC), Co-chairs of DM Technology Roadmap working group; Paul Bierden (BMC); Kevin King (AOX).

Astrophysics Division Strategic Astrophysics Technology (SAT) Program, and the NASA Small Business Innovation Research (SBIR) Program

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NASA Researcher Honored by Goddard Tech Office for Earth Science Work

Source: NASA

Goddard researcher Dr. Antonia Gambacorta the 2023 IRAD Innovator of the Year for her work developing hyperspectral microwave technology to dissect Earth’s atmosphere from orbit.

Earth science researcher Dr. Antonia Gambacorta earned the 2023 Goddard IRAD Technology Leadership award for pioneering new ways to measure lower layers of Earth’s atmosphere from space.
The award from the chief technologist of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, recognizes Gambacorta’s work demonstrating how hyperspectral microwave sounding, the measurement of hundreds of thousands of wavelengths of microwave light, could dissect Earth’s atmospheric planetary boundary layer (PBL). She also conceptualized a microwave photonics radiometer instrument to reveal these measurements.

The part of Earth’s atmosphere people live in, and have the most experience studying, is the hardest to measure from space due to the volume and complex behavior of the air above it, Gambacorta said. Developing the ability to probe and measure the boundary layer on a global, routine basis is important to better understanding its connections to the rest of our atmosphere, the land surface, and the oceans.
“The unique challenge of the PBL requires a novel path forward that will bring together traditionally disparate observing system components in order to enable transformative scientific advances in Earth system science,” said fellow researcher Joseph Santanello. “To that end, Dr. Gambacorta’s efforts extend beyond individual technology developments, and are represented in her aspirational vision of PBL sounding as ‘the tie that binds.’ Just as notably, Dr. Gambacorta’s passion, enthusiasm, and respect for her colleagues has been evident through each of stage of the project’s development.”
In seeking solutions to measure the boundary layer, Gambacorta stepped up to lead Goddard’s hyperspectral microwave projects and became the face of the center’s Decadal Survey Incubation (DSI) efforts. Through multiple Internal Research and Development, or IRAD grants, she and her team performed fundamental research to show the effectiveness of hyperspectral microwave sounding, conceptualized a microwave photonics radiometer instrument, and more recently began developing a framework to integrate data from multiple sensors for boundary layer science observations.

“Antonia’s innovation rises above her individual successes as a capable and creative innovator,” said Goddard Chief Technologist Peter Hughes. “She capitalized on multiple programs to incubate new technology while engaging expertise from across agencies and around the world to connect to other resources.”
Her cutting-edge innovations and research earned support from NASA’s Earth Science Technology Office and from the National Oceanic and Atmospheric Administration.
Specifically, Gambacorta built on her IRAD successes to secure an Earth Science Technology Office Instrument Incubator Program (IIP) project award to further develop her team’s microwave photonics radiometer concept and DSI funding to advance the multi-sensor fusion framework. Additionally, her momentum enabled a DSI-funded airborne instrument project attempting to transform CoSMIR, Goddard’s Conical Scanning Millimeter-wave Radiometer, into a hyperspectral sensor. That project is led by up-and-coming instrument scientist Rachael Kroodsma.
This entire portfolio that Gambacorta now manages also culminated in a successful NOAA Broad Agency Announcement proposal to demonstrate hyperspectral microwave radiometry. Through her engagement with colleagues in ESTO, NOAA, and the European Organisation for the Exploitation of Meteorological Satellites, Hughes said Goddard’s hyperspectral microwave and PBL initiatives are regarded globally as the trusted strategy for understanding the planetary boundary layer. Goddard is widely viewed as a pioneer in the use of integrated photonics for Earth remote sensing due to Gambacorta’s leadership, he added.
“Antonia serves as a true inspiration to the technologists and scientists on her teams,” her colleague Santanello added. “Her innovation and contribution to Goddard and the larger community can also be measured in each of these ways.”
By Karl B. Hille
NASA’s Goddard Space Flight Center, Greenbelt, Md.

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NASA Engineer Earns Goddard Innovation Award for Sun-studying Photon Sieves

Source: NASA

Goddard Engineer Kevin Denis receives innovation award for photon sieves.

Goddard’s Office of the Chief Technologist named engineer Steven Denis as the FY23 Internal Research and Development (IRAD) Innovator of the Year, an honor the office bestows annually on individuals who demonstrate the best in innovation.

Denis demonstrated persistence and innovation in developing hair-thin photon sieves to focus extreme ultraviolet light – a difficult wavelength to capture. Thin membranes matter for solar science, he said, because these sieves transmit up to seven times more light than thicker materials. Denis’s work will open new ways to study the Sun in better detail and understand its influence on Earth and the solar system.
Working closely with solar scientists over many years through Goddard ’s IRAD, or Internal Research and Development program, Denis developed new ways to create wider and thinner membranes of silicon and niobium. These photon sieves, created in Goddard’s Detector Development Laboratory, are so thin they must be supported by a honeycomb lattice of thicker silicon to prevent tearing. Etched with microscopic holes in a circular pattern, they refract light similar to Fresnel lenses used in lighthouses. Extreme ultraviolet light passing through this sieve is bent gradually inward to a distant receiver.

“It’s a sheer physical challenge to construct sieves with such precision,” said Goddard heliophysicist Dr. Doug Rabin. “Their smallest features are a few microns across. Kevin has really responded to that challenge with very creative solutions.”
Denis’s photon sieves should eventually be able to resolve features near the surface of the Sun 10 to 50 times smaller than can be seen today with the Solar Dynamics Observatory’s EUV imager, Rabin said.
Denis takes inspiration from working closely with scientists to overcome barriers to advancing their field, he said. “With this project in particular, scientists Rabin and Adrian Daw have done a great job using the sieves in near-term science applications while we push the technology for larger and more capable missions.”
Denis’s work was highlighted in Physics Today, a publication of the American Institute for Physics, for its importance in advancing pivotal technology that can address outstanding questions of how coronal heating and acceleration happens in the Sun’s lower atmosphere.
With two patents already awarded based on this project, Denis is submitting a new application for his latest fabrication process.
While he continues to push the limits of engineering, Denis said he is looking forward to seeing them used in missions of increasing complexity and capability. “It’s a great motivation to see they are going to be used for new science.”
By Karl B. Hille
NASA’s Goddard Space Flight Center in Greenbelt, Md.

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Deploying and Demonstrating Navigation Aids on the Lunar Surface

Source: NASA

Lunar Node-1 (LN-1)

NASA is developing lunar navigation beacons to be deployed on spacecraft or the lunar surface to aid in localization and help future space vehicles determine position, velocity, and time to high accuracy.

“Are we there yet?” is a constant question on any journey. As humanity expands its presence on, near, and around the Moon, new systems are needed to provide navigation signals similar those provided by the Global Positioning System (GPS) on Earth. To enable this capability, NASA is supporting research on a range of sensors, architectures, and techniques for providing reference signals to help spacecraft and humans find their way.

Lunar Node 1 (LN-1) is an S-band navigation beacon for lunar applications that was recently designed and built at Marshall Space Flight Center (MSFC). As part of NASA’s Commercial Lunar Payload Services (CLPS) initiative, this beacon is scheduled to be delivered to the Moon’s surface on Intuitive Machine’s NOVA-C lunar lander on the IM-1 mission in early 2024.

During this mission, LN-1’s goal will be to demonstrate navigation technologies that can support local surface and orbital operations around the Moon, enabling autonomy and decreasing dependence on heavily utilized Earth-based communication assets like NASA’s Deep Space Network demonstrate these capabilities, LN-1’s design leverages CubeSat components as well as the Multi-spacecraft Autonomous Positioning System (MAPS) algorithms, which enable autonomous spacecraft positioning using navigation measurements. In addition to demonstrating the MAPS algorithms, LN-1’s radio will also be used to conduct pseudo-noise (PN)-based, one-way, non-coherent ranging and Doppler tracking to provide alternate approaches and comparisons for navigation performance. To provide a real-time solution similar to GPS, but in the lunar environment, multiple references must be in view of users at the same time. As this future lunar communication network is deployed, LN-1 hardware and capabilities could be part of a much larger infrastructure.

Over the course of the transit to the Moon from Earth and during its the nominal lunar surface operations, LN-1 will broadcast its state and timing information back to Earth. Once it lands on the lunar surface, the payload will enter into a 24/7 operational period, and will also provide a navigation reference signal back to Earth.  To validate LN-1 capabilities, DSN ground stations will be used to capture measurements and measure performance. Upon reception of the LN-1 data, high-accuracy packet reception timestamps will be used (along with atmospheric data for induced delays) to assess a ranging observation. This data will be captured during multiple passes to compute a navigation state of the payload during the mission. The LN-1 team is also partnering with other NASA researchers to collect Very Long Baseline Interferometry observations of the navigation signals as an independent truth reference.

After completion and delivery of the LN-1 payload, testing with the planned operational ground stations began. This testing included RF compatibility testing between the DSN and the LN-1 payload as well as tests of the data flows between the DSN and MSFC’s Huntsville Operations Support Center. Performed at the DSN’s Development and Test Facility (DTF)-21 facility in early 2021, these tests successfully verified RF compatibility between DSN and the LN-1 payload. Specifically, the tests showed that the DSN can receive S-band telecommunication signals in all the planned operational modes required to process telemetry and ranging data from LN-1.

In the future, this new technology and the MAPS algorithms demonstrated by LN-1 could enable autonomous navigation for lunar assets. As NASA invests in communication and navigation infrastructure around, near, and on the Moon, the LN-1 team continues to develop future iterations of the navigation beacon to support broad lunar surface coverage. The team is currently maturing the capabilities of the payload in preparation for continued laboratory assessments and field demonstrations using updated navigation signals as defined for LunaNet. Three key capabilities will be the focus of the development of a follow-on payload to LN-1:

Demonstration of inter-spacecraft navigation, providing support to operational vehicles in lunar orbit by acting as a fixed ground reference
The capability to survive the lunar night onboard the payload to demonstrate technologies needed for a long-term navigation beacon
Maturation of signal to match the Augmented Forward Signal standard as defined in the LunaNet Interoperability Specification for integration, operation, and compatibility with other planned NASA assets and infrastructure

Dr. Evan Anzalone and Tamara Statham, NASA Marshall Space Flight Center (MSFC)

NASA-Provided Lunar Payloads Program

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Goddard Engineers Improve NASA Lidar Tech for Exploration, Navigation

Source: NASA

Lidar technology improvements will help NASA scientists and explorers with remote sensing and surveying, mapping, 3D-image scanning, hazard detection and avoidance, and navigation.

Like a sonar using light instead of sound, lidar technology increasingly helps NASA scientists and explorers with remote sensing and surveying, mapping, 3D-image scanning, hazard detection and avoidance, and navigation.
Cutting edge innovations by NASA researchers seek to refine lidars into smaller, lighter, more versatile tools for exploration.
“There are a lot of flavors of lidar right now,” said Cheryl Gramling, assistant chief for technology at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It’s such an important technology because of the precision and versatility that it offers.”
Light detection and ranging, or lidar, is a remote sensing technology related to sonar and radar. Lidar uses pulses of light to measure distances and properties of objects accurately, by measuring the time it takes the light to reflect back to the lidar sensor.
Goddard innovators are looking to expand the usefulness of lidar applications in communication and navigation, planetary exploration, and space operations. Here are a few of the current investigations.
Foldable, Flat Lidar Optics

Research engineer Mark Stephen is developing a deployable, segmented telescope to capture the returning light signal using state-of-the-art flat-panel optics organized in foldable, origami-inspired panels. Working with researchers at Brigham Young University, their team seeks to provide future missions with the benefits of lidar technology without the current technologies’ high cost and limited efficiency.
Lidar typically is a high-cost technology that may not make the cut for tomorrow’s smaller, lighter, and more efficient missions. Size, weight, and power demands limit the technology’s ability to be implemented in more missions.
“Most people want really high performance,” Stephen said, “But they want it in a small, light, and power-efficient package. We’re trying to find the best balance, and cost matters. Often the cost comes more from the size, weight, and power than it does from the actual development if we’re launching something into space. That is where it gets expensive.”
Stephen is wrapping up a three-year effort to improve lidars through a Radical Innovation Initiative grant within Goddard’s Internal Research and Development (IRAD) program. Their project has been picked up by NASA’s Earth Science Technology Office to fund further improvements.
Typically, lidar receivers depend on bulky lenses to capture light, each lens needs a specific curvature and size to bend the light, in addition to the structures which hold the lenses, and other mechanics, Stephen said. Larger lenses are more effective, and that is where lidar technology tends to get heavy.
Flat optics use new types of nano-structured materials to manipulate individual photons, he said. These meta-materials allow thin and lightweight optics to perform the same functions as much larger and more expensive three-dimensional counterparts.

“We are working toward being able to have a family of instruments where we have some flexibility and agility to meet the needs of a given mission,” Stephen said. “We want to develop a tool where you can make a better trade in terms of size, weight and power versus performance.”
One Laser, Many Wavelengths
Goddard engineer Guangning Yang is looking to improve lidar by producing multiple wavelengths of light from a single beam. Most modern lidars use multiple beams of a single wavelength to increase their accuracy.
Yang is the primary investigator for CASALS, or Concurrent Artificially intelligent Spectrometry and Adaptive Lidar System, a lidar technology that can sweep a large area more efficiently.
CASALS starts with one laser pulse, but instead of splitting that pulse into the many directions it needs to travel, their technology changes the wavelength of the laser at a very high speed. The different wavelengths of light then exit the laser transmitter at different angles based on their wavelength.
This pulse sequence produces a broom-like array sweeping across the object, landscape, or celestial body being studied.
“We have improved the efficiency,” Yang said, “and that will allow us to reduce the instrument’s size dramatically.”
Along with improvements in efficiency, CASALS is smaller than a typical lidar instrument. Yang said CASALS could help provide higher-density mapping of Earth and of other planets and moons as well as assisting with autonomous descents and landings.
Both flat optics and wavelength scanning offer new possibilities for lidar technology and are part of an array of investigations expected to unlock new opportunities in science and navigating distant worlds, Gramling said.
By Elizabeth Markham
NASA’s Goddard Space Flight Center in Greenbelt, Md.

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New Software Enables Atmospheric Modeling with Greater Resolution

Source: NASA

High Performance GEOS-Chem

An ESTO investment in software optimization helps researchers and citizen scientists model air quality and greenhouse gases with greater resolution, allowing them to better understand how global atmospheric trends impact local areas.

Next-generation software is making it easier for researchers, policy makers, and citizen scientists to model air quality and greenhouse gases using NASA meteorological data.

This novel software, “High Performance GEOS-Chem,” uses equations representing the Earth’s atmospheric chemistry and boundary conditions from NASA’s Goddard Earth Observation System (GEOS) to represent global atmospheric chemistry across three dimensions at a horizontal spatial resolution of 12 kilometers by 12 kilometers per pixel—an area about one-fifth the size of New York City.

For comparison, the original GEOS-Chem model that was developed in 2001 only produced global simulations at a spatial resolution of about 200 by 250 square kilometers – an area about twice as large as the entire state of New Jersey.

With this improved resolution, researchers interested in air quality and atmospheric chemistry in specific communities can use models, simulations, and visualizations built with NASA data to better understand how global atmospheric trends impact local areas.

GEOS-Chem is an open-source model freely accessible here. More information about High Performance Geos-Chem – including manuals and tutorials – can be found here.

“This new generation of High Performance GEOS-Chem offers major advancements for ease of use, computational performance, versatility, resolution, and accuracy,” said Randall Martin, a professor at Washington University’s McKelvey School of Engineering and Primary Investigator for the High Performance GEOS-Chem project.

In a recent technical demonstration of their improved GEOS-Chem software, Martin and his team showed two images mapping tropospheric nitrogen dioxide – a pollutant typically produced by burning fossil fuels.

The image produced with High Performance GEOS-Chem featured 200 million more grid cells than the image produced with the original GEOS-Chem software. In other words, High Performance GEOS-Chem creates images more resolute by a factor of about 200.

“We’re really excited. Many features can be examined that aren’t resolved at all at the coarser resolution,” said Martin.

For researchers interested in global air quality and atmospheric composition with local resolution, this new generation of the High Performance GEOS-Chem marks the beginning of a new era for creating descriptive models.

Martin and his team added a number of technological innovations to High Performance GEOS-Chem. In particular, they incorporated a cubed-sphere computation grid into their GEOS-Chem software, reducing noise at the poles and allowing for higher resolution.

High Performance GEOS-Chem also includes a cloud computing capability. This spreads the resource-intensive computation work of generating detailed atmospheric models across dispersed computing nodes, such as Amazon Web Services.

Martin and his team pride themselves on ensuring GEOS-Chem remains an open and accessible tool for anyone interested in simulating atmospheric composition. Their website includes a full suite of tutorial videos, manuals, and guides for using GEOS-Chem effectively.

“NASA enabled us to develop this new generation of GEOS-Chem that has both the additional technical performance and offers the ease of use that this large community requires,” said Martin.

Future iterations of GEOS-Chem could feature further improvements. Developing a better user interface and increasing the modularity of GEOS-Chem are just a few objectives Martin and his team have in mind.

NASA’s Advanced Information Systems Technology (AIST), a part of NASA’s Earth Science Technology Office (ESTO), funded this program.

Randall Martin, Washington University in St. Louis

Earth Science Division’s Advanced Information Systems Technology (AIST) Program