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By NASA
Since its launch in 2014, the Physical Sciences Informatics (PSI) system has served as NASA’s online repository for physical science data. Now, the PSI system is live with new updates to further align with NASA’s open data policy.
With its first significant update in over five years, the data repository has been completely redesigned, featuring a new layout, improved structure, and enhanced search functionalities. This updated system was created with a focus on user experience, and more updates are anticipated as new features are introduced.
A key new feature of the system is, the PSI Submission Portal. This tool is designed to streamline the processes of collecting, curating, and publishing new data by enabling Principal Investigators and scientific teams to upload files directly to the system with the support of a data curator. The Portal also offers a dedicated workspace for data submitters, assigns a unique digital object identifier to each dataset, and standardizes the documentation and data structure for each investigation.
Both the updated PSI system and Submission Portal can be accessed at PSI.NASA.gov.
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By NASA
Name: Christine Knudson
Title: Geologist
Formal Job Classification: Research Assistant
Organization: Planetary Environments Laboratory, Science Directorate (Code 699)
Christine Knudson is a geologist at NASA’s Goddard Space Flight Center in Greenbelt, Md. She began graduate school in August 2012, the same month that NASA’s Curiosity rover landed on Mars. “It is very exciting to be part of the rover team and to be involved in an active Mars mission,” she says. “On days when we’re downlinking science data and I’m on shift, I am one of the first people to see data from an experiment done on Mars!”Courtesy of Christine Knudsen What do you do and what is most interesting about your role here at Goddard?
I am a geologist doing both laboratory and field work, primarily focusing on Mars analog research. I work on the Curiosity rover as part of the Sample Analysis at Mars (SAM) instrument team.
Why did you become a geologist?
As a child, I always loved being outside and I was really interested in all things related to the Earth. In college, I figured out that I wanted to be a geologist after taking an introduction to geology course. I wanted to learn more about the Earth and its interior, specifically volcanism.
What is your educational background?
In 2012, I received a B.S. in geology and environmental geoscience from Northern Illinois University. In August 2012, the same month that Curiosity landed on Mars, I started graduate school and in December 2014, I received a M.S. in geology from the same university. I focused on igneous geochemistry, investigating the pre-eruptive water contents of a Guatemalan volcano.
Why did you come to Goddard?
I came to Goddard in February 2015 to perform laboratory analyses of Mars analog materials, rock and mineral samples, from Earth, that the Curiosity rover and spectral orbiters have also identified on Mars. It is very exciting to be part of the rover team and to be involved in an active Mars mission.
What is a highlight of your work as a laboratory geologist doing Mars analog research?
Using laboratory analyses to interpret data we are getting back from Curiosity is incredibly exciting! I perform evolved gas analysis to replicate the analyses that the SAM instrument does on the rover. Curiosity scoops sand or drills into the rocks at stops along its drive through Gale Crater on Mars, then dumps the material into a small cup within the SAM instrument inside the rover. The rock is heated in a small oven to about 900 C [about 1650 F], and the instrument captures the gases that are released from the sample as it is heated. SAM uses a mass spectrometer to identify the different gases, and that tells us about the minerals that make up the rock.
We do the same analyses on rocks and minerals in our lab to compare to the SAM analyses. The other instruments on Curiosity also aid in the identification of the rocks, minerals, and elements present in this location on the Martian surface.
I also serve as a payload downlink lead for the SAM instrument. I check on the science and engineering data after we perform an experiment on Mars. On the days I’m on shift, I check to make sure that our science experiments finish without any problems, and that the instrument is “healthy,” so that the rover can continue driving and begin the science that is planned for the next sol.
On days when we’re downlinking science data and I’m on shift, I am one of the first people to see data from an experiment done on Mars!
What is some of the coolest field work you have done?
I have done Mars analog field work in New Mexico, Hawaii, and Iceland. The field work in Hawaii is exciting because one of our field sites was inside a lava tube on Mauna Loa. We expect that there are lava tubes on Mars, and we know that the interior of the tubes would likely be better shielded from solar radiation, which might allow for the preservation of organic markers. Scientifically, we’re interested in characterizing the rocks and minerals inside lava tubes to understand how the interior differs from the surface over time and to investigate differences in elemental availability as an accessible resource for potential life. Learning about these processes on Earth helps us understand what might be possible on Mars too.
“The field work in Hawaii is exciting because one of our field sites was inside a lava tube on Mauna Loa,” Knudson says. “We expect that there are lava tubes on Mars, and we know that the interior of the tubes would likely be better shielded from solar radiation, which might allow for the preservation of organic markers.”Courtesy of Christine Knudson I use handheld versions of laboratory instruments, some of which were miniaturized and made to fit on the Curiosity rover, to take in situ geochemical measurements — to learn what elements are present in the rocks and in what quantities. We also collect samples to analyze in the laboratory.
I also love Hawaii because the island is volcanically active. Hawaii Volcano National Park is incredible! A couple years ago, I was able to see the lava lake from an ongoing eruption within the crater of Kīlauea volcano. The best time to see the lava lake is at night because the glowing lava is visible from multiple park overlooks.
As a Mars geologist, what most fascinates you about the Curiosity rover?
When Curiosity landed, it was the largest rover NASA had ever sent to Mars: It’s about the size of a small SUV, so landing it safely was quite the feat! Curiosity also has some of the first science instruments ever made to operate on another planet, and we’ve learned SO much from those analyses.
Curiosity and the other rovers are sort of like robotic geologists exploring Mars. Working with the Curiosity rover allows scientists to do geology on Mars — from about 250 million miles away! Earth analogs help us to understand what we are seeing on Mars, since that “field site” is so incredibly far away and inaccessible to humans at this time.
What do you do for fun?
I spend most of my free time with my husband and two small children. We enjoy family hikes, gardening, and both my boys love being outside as much as I do.
I also enjoy yoga, and I crochet: I make hats, blankets, and I’m starting a sweater soon.
What is your “six-word memoir”? A six-word memoir describes something in just six words.
Nature-lover. Mom. Geologist. Cat-enthusiast. Curious. Snack-fiend.
By Elizabeth M. Jarrell
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Conversations With Goddard is a collection of Q&A profiles highlighting the breadth and depth of NASA’s Goddard Space Flight Center’s talented and diverse workforce. The Conversations have been published twice a month on average since May 2011. Read past editions on Goddard’s “Our People” webpage.
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Last Updated Oct 16, 2024 EditorRob GarnerContactRob Garnerrob.garner@nasa.govLocationGoddard Space Flight Center Related Terms
The Solar System Curiosity (Rover) Mars Mars Science Laboratory (MSL) People of Goddard People of NASA Explore More
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By NASA
The study of X-ray emission from astronomical objects reveals secrets about the Universe at the largest and smallest spatial scales. Celestial X-rays are produced by black holes consuming nearby stars, emitted by the million-degree gas that traces the structure between galaxies, and can be used to predict whether stars may be able to host planets hospitable to life. X-ray observations have shown that most of the visible matter in the universe exists as hot gas between galaxies and have conclusively demonstrated that the presence of “dark matter” is needed to explain galaxy cluster dynamics, that dark matter dominates the mass of galaxy clusters, and that it governs the expansion of the cosmos.
X-ray observations also enable us to probe mysteries of the Universe on the smallest scales. X-ray observations of compact objects such as white dwarfs, neutron stars, and black holes allow us to use the Universe as a physics laboratory to study conditions that are orders of magnitude more extreme in terms of density, pressure, temperature, and magnetic field strength than anything that can be produced on Earth. In this astrophysical laboratory, researchers expect to reveal new physics at the subatomic scale by conducting investigations such as probing the neutron star equation of state and testing quantum electrodynamics with observations of neutron star atmospheres. At NASA’s Marshall Space Flight Center, a team of scientists and engineers is building, testing, and flying innovative optics that bring the Universe’s X-ray mysteries into sharper focus.
A composite X-ray/Optical/Infrared image of the Crab Pulsar. The X-ray image from the Chandra X-ray Observatory (blue and white), reveals exquisite details in the central ring structures and gas flowing out of the polar jets. Optical light from the Hubble Space Telescope (purple) shows foreground and background stars as pinpoints of light. Infrared light from the Spitzer Space Telescope (pink) traces cooler gas in the nebula. Finally, magnetic field direction derived from X-ray polarization observed by the Imaging X-ray Polarimetry Explorer is shown as orange lines. Magnetic field lines: NASA/Bucciantini et al; X-ray: NASA/CXC/SAO; Optical: NASA/STScI; Infrared: NASA-JPL-Caltech Unlike optical telescopes that create images by reflecting or refracting light at near-90-degree angles (normal incidence), focusing X-ray optics must be designed to reflect light at very small angles (grazing incidence). At normal incidence, X-rays are either absorbed by the surface of a mirror or penetrate it entirely. However, at grazing angles of incidence, X-rays reflect very efficiently due to an effect called total external reflection. In grazing incidence, X-rays reflect off the surface of a mirror like rocks skipping on the surface of a pond.
A classic design for astronomical grazing incidence optics is the Wolter-I prescription, which consists of two reflecting surfaces, a parabola and hyperbola (see figure below). This optical prescription is revolved around the optical axis to produce a full-shell mirror (i.e., the mirror spans the full circumference) that resembles a gently tapered cone. To increase the light collecting area, multiple mirror shells with incrementally larger diameters and a common focus are fabricated and nested concentrically to comprise a mirror module assembly (MMA).
Focusing optics are critical to studying the X-ray universe because, in contrast to other optical systems like collimators or coded masks, they produce high signal-to-noise images with low background noise. Two key metrics that characterize the performance of X-ray optics are angular resolution, which is the ability of an optical system to discriminate between closely spaced objects, and effective area, which is the light collecting area of the telescope, typically quoted in units of cm2. Angular resolution is typically measured as the half-power diameter (HPD) of a focused spot in units of arcseconds. The HPD encircles half of the incident photons in a focused spot and measures the sharpness of the final image; a smaller number is better.
Schematic of a full-shell Wolter-I X-ray optic mirror module assembly with five concentrically nested mirror shells. Parallel rays of light enter from the left, reflect twice off the reflective inside surface of the shell (first off the parabolic segment and then off the hyperbolic segment), and converge at the focal plane. NASA MSFC NASA Marshall Space Flight Center (MSFC) has been building and flying lightweight, full-shell, focusing X-ray optics for over three decades, always meeting or exceeding angular resolution and effective area requirements. MSFC utilizes an electroformed nickel replication (ENR) technique to make these thin full-shell X-ray optics from nickel alloy.
X-ray optics development at MSFC began in the early 1990s with the fabrication of optics to support NASA’s Advanced X-ray Astrophysics Facility (AXAF-S) and then continued via the Constellation-X technology development programs. In 2001, MSFC launched a balloon payload that included two modules each with three mirrors, which produced the first focused hard X-ray (>10 keV) images of an astrophysical source by imaging Cygnus X-1, GRS 1915, and the Crab Nebula. This initial effort resulted in several follow-up missions over the next 12 years, and became known as the High Energy Replicated Optics (HERO) balloon program.
In 2012, the first of four sounding rocket flights of the Focusing Optics X-ray Solar Imager (FOXSI) flew with MSFC optics onboard, producing the first focused images of the Sun at energies greater than 5 keV. In 2019 the Astronomical Roentgen Telescope X-ray Concentrator (ART-XC) instrument on the Spectr-Roentgen-Gamma Mission launched with seven MSFC-fabricated X-ray MMAs, each containing 28 mirror shells. ART-XC is currently mapping the sky in the 4-30 keV hard X-ray energy range, studying exotic objects like neutron stars in our own galaxy as well as active galactic nuclei, which are spread across the visible universe. In 2021, the Imaging X-ray Polarimetry Explorer (IXPE), flew and is now performing extraordinary science with an MSFC-led team using three, 24-shell MMAs that were fabricated and calibrated in-house.
Most recently, in 2024, the fourth FOXSI sounding rocket campaign launched with a high-resolution MSFC MMA. The optics achieved 9.5 arcsecond HPD angular resolution during pre-flight test with an expected 7 arcsecond HPD in gravity-free flight, making this the highest angular resolution flight observation made with a nickel-replicated X-ray optic. Currently MSFC is fabricating an MMA for the Rocket Experiment Demonstration of a Soft X-ray (REDSoX) polarimeter, a sounding rocket mission that will fly a novel soft X-ray polarimeter instrument to observe active galactic nuclei. The REDSoX MMA optic will be 444 mm in diameter, which will make it the largest MMA ever produced by MSFC and the second largest replicated nickel X-ray optic in the world.
Scientists Wayne Baumgartner (left, crouched) and Nick Thomas (left, standing) calibrate an IXPE MMA in the MSFC 100 m Beamline. Scientist Stephen Bongiorno (right) applies epoxy to an IXPE shell during MMA assembly. NASA MSFC The ultimate performance of an X-ray optic is determined by errors in the shape, position, and roughness of the optical surface. To push the performance of X-ray optics toward even higher angular resolution and achieve more ambitious science goals, MSFC is currently engaged in a fundamental research and development effort to improve all aspects of full-shell optics fabrication.
Given that these optics are made with the Electroformed Nickel Replication technique, the fabrication process begins with creation of a replication master, called the mandrel, which is a negative of the desired optical surface. First, the mandrel is figured and polished to specification, then a thin layer of nickel alloy is electroformed onto the mandrel surface. Next, the nickel alloy layer is removed to produce a replicated optical shell, and finally the thin shell is attached to a stiff holding structure for use.
Each step in this process imparts some degree of error into the final replicated shell. Research and development efforts at MSFC are currently concentrating on reducing distortion induced during the electroforming metal deposition and release steps. Electroforming-induced distortion is caused by material stress built into the electroformed material as it deposits onto the mandrel. Decreasing release-induced distortion is a matter of reducing adhesion strength between the shell and mandrel, increasing strength of the shell material to prevent yielding, and reducing point defects in the release layer.
Additionally, verifying the performance of these advanced optics requires world-class test facilities. The basic premise of testing an optic designed for X-ray astrophysics is to place a small, bright X-ray source far away from the optic. If the angular size of the source, as viewed from the optic, is smaller than the angular resolution of the optic, the source is effectively simulating X-ray starlight. Due to the absorption of X-rays by air, the entire test facility light path must be placed inside a vacuum chamber.
At MSFC, a group of scientists and engineers operate the Marshall 100-meter X-ray beamline, a world-class end-to-end test facility for flight and laboratory X-ray optics, instruments, and telescopes. As per the name, it consists of a 100-meter-long vacuum tube with an 8-meter-long, 3-meter-diameter instrument chamber and a variety of X-ray sources ranging from 0.25 – 114 keV. Across the street sits the X-Ray and Cryogenic Facility (XRCF), a 527-meter-long beamline with an 18-meter-long, 6-meter-diameter instrument chamber. These facilities are available for the scientific community to use and highlight the comprehensive optics development and test capability that Marshall is known for.
Within the X-ray astrophysics community there exist a variety of angular resolution and effective area needs for focusing optics. Given its storied history in X-ray optics, MSFC is uniquely poised to fulfill requirements for large or small, medium- or high-angular-resolution X-ray optics. To help guide technology development, the astrophysics community convenes once per decade to produce a decadal survey. The need for high-angular-resolution and high-throughput X-ray optics is strongly endorsed by the National Academies of Sciences, Engineering, and Medicine report, Pathways to Discovery in Astronomy and Astrophysics for the 2020s.In pursuit of this goal, MSFC is continuing to advance the state of the art in full-shell optics. This work will enable the extraordinary mysteries of the X-ray universe to be revealed.
Project Leads
Dr. Jessica Gaskin and Dr. Stephen Bongiorno, NASA Marshall Space Flight Center (MSFC)
Sponsoring Organizations
The NASA Astrophysics Division supports this work primarily through the Internal Scientist Funding Model Direct Work Package and competed solicitations. This work is also supported by the Heliophysics Division through competed solicitations, as well as by directed work from other government entities.
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Last Updated Oct 15, 2024 Related Terms
Astrophysics Astrophysics Division Marshall Astrophysics Marshall Space Flight Center Science-enabling Technology Technology Highlights Explore More
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