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    • By NASA
      Humans are returning to the Moon—this time, to stay. Because our presence will be more permanent, NASA has selected a location that maximizes line-of-sight communication with Earth, solar visibility, and access to water ice: the Lunar South Pole (LSP). While the Sun is in the lunar sky more consistently at the poles, it never rises more than a few degrees above the horizon; in the target landing regions, the highest possible elevation is 7°. This presents a harsh lighting environment never experienced during the Apollo missions, or in fact, in any human spaceflight experience. The ambient lighting will severely affect the crews’ ability to see hazards and to perform simple work. This is because the human vision system, which despite having a high-dynamic range, cannot see well into bright light and cannot adapt quickly from bright to dark or vice versa. Functional vision is required to perform a variety of tasks, from simple tasks (e.g., walking, operating simple tools) through managing complex machines (e.g., lander elevator, rovers). Thus, the environment presents an engineering challenge to the Agency: one that must be widely understood before it can be effectively addressed.

       In past NASA missions and programs, design of lighting and functional vision support systems for extravehicular activity (EVA) or rover operations have been managed at the lowest program level. This worked well for Apollo and low Earth orbit because the Sun angle was managed by mission planning and astronaut self-positioning; helmet design alone addressed all vision challenges. The Artemis campaign presents new challenges to functional vision, because astronauts will be unable to avoid having the sun in their eyes much of the time they are on the lunar surface. This, combined with the need for artificial lighting in the extensive shadowing at the LSP, means that new functional vision support systems must be developed across projects and programs. The design of helmets, windows, and lighting systems must work in a complementary fashion, within and across programs, to achieve a system of lighting and vision support that enables crews to see into darkness while their eyes are light-adapted, in bright light while still dark-adapted, and protects their eyes from injury.
      Many of the findings of the assessment were focused on the lack of specific requirements to prevent functional vision impairment by the Sun’s brilliance (which is different from preventing eye injury), while enabling astronauts to see well enough to perform specific tasks. Specifically, tasks expected of astronauts at the LSP were not incorporated into system design requirements to enable system development that ensures functional vision in the expected lighting environment. Consequently, the spacesuit, for example, has flexibility requirements for allowing the astronauts to walk but not for ensuring they can see well enough to walk from brilliant Sun into a dark shadow and back without the risk of tripping or falling. Importantly, gaps were identified in allocation of requirements across programs to ensure that the role of the various programs is for each to understand functional vision. NESC recommendations were offered that made enabling functional vision in the harsh lighting environment a specific and new requirement for the system designers. The recommendations also included that lighting, window, and visor designs be integrated.
      The assessment team recommended that a wide variety of simulation techniques, physical and virtual, need to be developed, each with different and well-stated capabilities with respect to functional vision. Some would address the blinding effects of sunlight at the LSP (not easily achieved through virtual approaches) to evaluate performance of helmet shields and artificial lighting in the context of the environment and adaptation times. Other simulations would add terrain features to identify the threats in simple (e.g., walking, collection of samples) and complex (e.g., maintenance and operation of equipment) tasks. Since different facilities have different strengths, they also have different weaknesses. These strengths and limitations must be characterized to enable verification of technical solutions and crew training.
      NESC TB 2024- discipline-focus-hfView the full article
    • By NASA
      ESA/Webb, NASA & CSA, P. Zeidler This new image of star cluster NGC 602, released on Dec. 17, 2024, combines data from NASA’s Chandra X-ray Observatory with a previously released image from the agency’s James Webb Space Telescope. Webb data provide the ring-like outline of the “wreath,” while X-rays from Chandra (red) show young, massive stars that are illuminating the wreath, sending high-energy light into interstellar space.
      NGC 602 lies on the outskirts of the Small Magellanic Cloud, which is one of the closest galaxies to the Milky Way, about 200,000 light-years from Earth. 
      See another new, festive image: the “Christmas tree cluster.”
      Image credit: X-ray: NASA/CXC; Infrared: ESA/Webb, NASA & CSA, P. Zeilder, E.Sabbi, A. Nota, M. Zamani; Image Processing: NASA/CXC/SAO/L. Frattare and K. Arcand
      View the full article
    • By NASA
      X-rays are radiated by matter hotter than one million Kelvin, and high-resolution X-ray spectroscopy can tell us about the composition of the matter and how fast and in what direction it is moving. Quantum calorimeters are opening this new window on the Universe. First promised four decades ago, the quantum-calorimeter era of X-ray astronomy has finally dawned.
      Photo of the XRISM/Resolve quantum-calorimeter array in its storage container prior to integration into the instrument. The 6×6 array, 5 mm on a side, consists of independent detectors – each one a thermally isolated silicon thermistor with a HgTe absorber. The spectrometer consisting of this detector and other essential technologies separates astrophysical X-ray spectra into about 2400 resolution elements, which can be thought of as X-ray colors.NASA GSFC A quantum calorimeter is a device that makes precise measurements of energy quanta by measuring the temperature change that occurs when a quantum of energy is deposited in an absorber with low heat capacity. The absorber is attached to a thermometer that is somewhat decoupled from a heat sink so that the sensor can heat up and then cool back down again. To reduce thermodynamic noise and the heat capacity of the sensor, operation at temperatures less than 0.1 K is required. 
      The idea for thermal measurement of small amounts of energy occurred in several places in the world independently when scientists observed pulses in the readout of low-temperature thermometers and infrared detectors. They attributed these spurious signals to passing cosmic-ray particles, and considered optimizing detectors for sensitive measurement of the energy of particles and photons.
      The idea to develop such sensors for X-ray astronomy was conceived at Goddard Space Flight Center in 1982 when X-ray astronomers were considering instruments to propose for NASA’s planned Advanced X-ray Astrophysics Facility (AXAF). In a fateful conversation, infrared astronomer Harvey Moseley suggested thermal detection could offer substantial improvement over existing solid-state detectors. Using Goddard internal research and development funding, development advanced sufficiently to justify, just two years later, proposing a quantum-calorimeter X-ray Spectrometer (XRS) for inclusion on AXAF. Despite its technical immaturity at the time, the revolutionary potential of the XRS was acknowledged, and the proposal was accepted.
      The AXAF design evolved over the subsequent years, however, and the XRS was eliminated from its complement of instruments. After discussions between NASA and the Japanese Institute of Space and Astronautical Science (ISAS), a new XRS was included in the instrument suite of the Japanese Astro-E X-ray observatory. Astro-E launched in 2000 but did not reach orbit due to an anomaly in the first stage of the rocket. Astro-E2, a rebuild of Astro-E, was successfully placed in orbit in 2005 and renamed Suzaku, but the XRS instrument ceased operation before observations started due to loss of the liquid helium, an essential part of the detector cooling system, caused by a faulty storage system.
      A redesigned mission, Astro-H, that included a quantum-calorimeter instrument with a redundant cooling system was successfully launched in 2016 and renamed Hitomi. Hitomi’s Soft X-ray Spectrometer (SXS) obtained high resolution spectra of the Perseus cluster of galaxies and a few other sources before a problem with the attitude control system caused the mission to be lost roughly one month after launch. Even so, Hitomi was the first orbiting observatory to obtain a scientific result using X-ray quantum calorimeters. The spectacular Perseus spectrum generated by the SXS motivated yet another attempt to implement a spaceborne quantum-calorimeter spectrometer.
      The X-ray Imaging and Spectroscopy Mission (XRISM) was launched in September 2023, with the spectrometer aboard renamed Resolve to represent not only its function but also the resolve of the U.S./Japan collaboration to study the Universe through the window of this new capability. XRISM has been operating well in orbit for over a year.  
      Development of the Sensor Technology
      Development of the sensor technology employed in Resolve began four decades ago. Note that an X-ray quantum-calorimeter spectrometer requires more than the sensor technology. Other technologies, such as the coolers that provide a
      The sensors used from XRS through Resolve were all based on silicon-thermistor thermometers and mercury telluride (HgTe) X-ray absorbers. They used arrays consisting of 32 to 36 pixels, each of which was an independent quantum calorimeter.  Between Astro-E and Astro-E2, a new method of making the thermistor was developed that significantly reduced its low-frequency noise. Other fabrication advances made it possible to make reproducible connections between absorbers and thermistors and to fit each thermistor and its thermal isolation under its X-ray absorber, making square arrays feasible.
      Through a Small Business Innovation Research (SBIR) contract executed after the Astro-E2 mission, EPIR Technologies Inc. reduced the specific heat of the HgTe absorbers. Additional improvements made to the cooler of the detector heat sink allowed operation at a lower temperature, which further reduced the specific heat. Together, these changes enabled the pixel width to be increased from 0.64 mm to 0.83 mm while still achieving a lower heat capacity, and thus improving the energy resolution. From Astro-E through Astro-H, the energy resolution for X-rays of energy around 6000 eV improved from 11 eV, to 5.5 eV, to 4 eV. No changes to the array design were made between Astro-H and XRISM.
      Resolve detector scientist Caroline Kilbourne installing the flight Resolve quantum-calorimeter array into the assembly that provides its electrical, thermal, and mechanical interfaces.NASA GSFC Over the same period, other approaches to quantum-calorimeter arrays optimized for the needs of future missions were developed. The use of superconducting transition-edge sensors (TES) instead of silicon (Si) thermistors led to improved energy resolution, more pixels per array, and multiplexing (a technique that allows multiple signals to be carried on a single wire). Quantum-calorimeter arrays with thousands of pixels are now standard, such as in the NASA contribution to the future European New Advanced Telescope for High-ENergy Astrophysics (newAthena) mission. And quantum calorimeters using paramagnetic thermometers — which unlike TES and Si thermistors require no dissipation of heat in the thermometer for it to be read out — combined with high-density wiring are a promising route for realizing even larger arrays. (See Astrophysics Technology Highlight on these latest developments.)
      The Resolve instrument aboard XRISM (X-ray Imaging and Spectroscopy Mission) captured data from the center of galaxy NGC 4151, where a supermassive black hole is slowly consuming material from the surrounding accretion disk. The resulting spectrum reveals the presence of iron in the peak around 6.5 keV and the dips around 7 keV, light thousands of times more energetic that what our eyes can see. Background: An image of NGC 4151 constructed from a combination of X-ray, optical, and radio light.Spectrum: JAXA/NASA/XRISM Resolve. Background: X-rays, NASA/CXC/CfA/J.Wang et al.; optical, Isaac Newton Group of Telescopes, La Palma/Jacobus Kapteyn Telescope; radio, NSF/NRAO/VLA Results from Resolve
      So, what is Resolve revealing about the Universe? Through spectroscopy alone, Resolve allows us to construct images of complex environments where collections of gas and dust with various attributes exist, emitting and absorbing X-rays at energies characteristic of their various compositions, velocities, and temperatures. For example, in the middle of the galaxy known as NCG 4151 (see figure above), matter spiraling into the central massive black hole forms a circular structure that is flat near the black hole, more donut-shaped further out, and, according to the Resolve data, a bit lumpy. Matter near the black hole is heated up to X-ray-emitting temperatures and irradiates the matter in the circular structure. The Resolve spectrum has a bright narrow emission line (peak) from neutral iron atoms that must be coming from colder matter in the circular structure, because hotter material would be ionized, and would have a different emission signature. Nonetheless, the shape of the iron line needs three components to describe it, each coming from a different lump in the circular structure. The presence of absorption lines (dips) in the spectrum provides further detail about the structure of the infalling matter.
      A second example is the detection of X-ray emission by Resolve from the debris of stars that have exploded, such as N132D (see figure below), that will improve our understanding of the explosion mechanism and how the elements produced in stars get distributed, and allow us to infer the type of star each was before ending in a supernova. Elements are identified by their characteristic emission lines, and shifts of those lines via the Doppler effect tell us how fast the material is moving.
      XRISM’s Resolve instrument captured data from supernova remnant N132D in the Large Magellanic Cloud to create the most detailed X-ray spectrum of the object ever made. The spectrum reveals peaks associated with silicon, sulfur, argon, calcium, and iron. Inset at right is an image of N132D captured by XRISM’s Xtend instrument.JAXA/NASA/XRISM Resolve and Xtend These results are just the beginning. The rich Resolve data sets are identifying complex velocity structures, rare elements, and multiple temperature components in a diverse ensemble of cosmic objects. Welcome to the quantum calorimeter era! Stay tuned for more revelations!
      Project Leads: Dr. Caroline Kilbourne, NASA Goddard Space Flight Center (GSFC), for silicon-thermistor quantum calorimeter development from Astro-E2 through XRISM and early TES development. Foundational and other essential leadership provided by Dr. Harvey Moseley, Dr. John Mather, Dr. Richard Kelley, Dr. Andrew Szymkowiak, Mr. Brent Mott, Dr. F. Scott Porter, Ms. Christine Jhabvala, Dr. James Chervenak (GSFC at the time of the work) and Dr. Dan McCammon (U. Wisconsin).
      Sponsoring Organizations and Programs:  The NASA Headquarters Astrophysics Division sponsored the projects, missions, and other efforts that culminated in the development of the Resolve instrument.
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    • By NASA
      5 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      A scientific balloon is inflated during NASA’s 2023 Antarctic campaign in McMurdo, Antarctica. NASA/Scott Battaion NASA’s Scientific Balloon Program has returned to Antarctica’s icy expanse to kick off the annual Antarctic Long-Duration Balloon Campaign, where two balloon flights will carry a total of nine missions to near space. Launch operations will begin mid-December from the agency’s Long Duration Balloon camp located near the U.S. National Science Foundation’s McMurdo Station on the Ross Ice Shelf.
      “Antarctica is our cornerstone location for long-duration balloon missions, and we always look forward to heading back to ‘the ice,’” said Andrew Hamilton, acting chief of NASA’s Balloon Program Office at the agency’s Wallops Flight Facility in Virginia. “It’s a tremendous effort to stage a campaign like this in such a remote location, and we are grateful for the support provided to us by the U.S. National Science Foundation, New Zealand, and the U.S. Air Force.”
      This year’s Antarctic campaign includes investigations in astrophysics, space biology, heliospheric research, and upper atmospheric research, along with technology demonstrations. The campaign’s two primary missions include:
      GAPS (General Anti-Particle Spectrometer), led by Columbia University in New York, is an experiment to detect anti-matter particles produced by dark matter interactions. The anti-particles stemming from these interactions in our galaxy can only be observed from a suborbital platform or in space, since Earth’s atmosphere shields us from the cosmic radiation. GAPS aims to provide an unprecedented level of sensitivity to certain classes of anti-particles, allowing the exploration of a currently unexplored energy regime of the elusive dark matter. Salter Test Flight Universal, led by NASA’s Columbia Scientific Balloon Facility in Palestine, Texas, will test and validate long-duration balloon and subsystems, while supporting several piggyback missions on the flight. Piggyback missions, or smaller payloads, riding along with the Salter Test Flight Universal mission include:
      MARSBOx (Microbes in Atmosphere for Radiation, Survival, and Biological Outcomes Experiments), led by the U.S. Naval Research Laboratory, will expose melanized fungus, called Aspergillus niger, to the stratosphere’s extreme radiation and temperature fluctuations, low atmospheric pressure, and absence of water — conditions much like the surface of Mars. Knowledge of how this fungus adapts to protect itself in this harsh environment could lead to the development of treatments to protect astronauts from high radiation exposure. EMIDSS-6 (Experimental Module for Iterative Design of Satellite Subsystems 6), led by National Polytechnical Institute − Mexico, is a technological platform with experimental design and operational validation of instrumentation that will collect and store data from the stratospheric environment to contribute to the study of climate change. SPARROW-6 (Sensor Package for Attitude, Rotation, and Relative Observable Winds – 6), led by NASA’s Balloon Program Office at NASA Wallops, will demonstrate relative wind measurements using an ultrasonic anemometer designed for the balloon float environment.   WALRUSS (Wallops Atmospheric Light Radiation and Ultraviolet Spectrum Sensor), led by the Balloon Program Office at NASA Wallops, is a technology demonstration of a sensor package capable of measuring the total ultraviolet wavelength spectrum and ozone concentration. INDIGO (INterim Dynamics Instrumentation for Gondolas), led by the Balloon Program Office at NASA Wallops, is a data recorder meant to measure the shock, rotation, and attitude of the gondola during the launch, float, and landing phases of flight. Data will be used to improve understanding of the dynamics of flight and to inform the design of future components and hardware. The remaining two piggyback missions are led by finalists of NASA’s FLOATing DRAGON (Formulate, Lift, Observe, And Testing; Data Recovery And Guided On-board Node) Balloon Challenge, sponsored by the Balloon Program Office at NASA Wallops and managed by the National Institute of Aerospace. The challenge was created for student teams to design, build, and fly an autonomous aerial vehicle, deployed from a gondola during a high-altitude balloon flight. The teams’ student-built data vaults will be safely dropped from around 120,000 feet with the capability to target a specific landing point on the ground to manage risk. The missions participating in the Antarctic campaign are Purdue University’s Purdue DRAGONfly, and University of Notre Dame’s IRIS v3.
      NASA’s zero-pressure balloons, used in the Antarctic campaign, are made of a thin plastic film and are capable of lifting up to 8,000 pounds of payload and equipment to altitudes above 99.8% of Earth’s atmosphere. Zero-pressure balloons, which typically have a shorter flight duration from the loss of gas during the day-to-night cycle, can support long-duration missions in polar regions during summer. The constant daylight of Antarctica’s austral summer and stable stratospheric wind conditions allow the balloon missions to remain in near space for days to weeks, gathering large amounts of scientific data as they circle the continent.
      NASA’s Long Duration Balloon camp is located about eight miles from the U.S. National Science Foundation’s McMurdo Station on Antarctica’s Ross Ice Shelf. NASA/Scott Battaion NASA’s Wallops Flight Facility in Virginia manages the agency’s scientific balloon flight program with 10 to 15 flights each year from launch sites worldwide. Peraton, which operates NASA’s Columbia Scientific Balloon Facility in Palestine, Texas, provides mission planning, engineering services, and field operations for NASA’s scientific balloon program. The Columbia team has launched more than 1,700 scientific balloons over some 40 years of operations. NASA’s balloons are fabricated by Aerostar. The NASA Scientific Balloon Program is funded by the NASA Headquarters Science Mission Directorate Astrophysics Division. NASA balloon launch operations from Antarctica receive logistical support from the U.S. National Science Foundation’s Office of Polar Programs, which oversees the U.S. Antarctic Program.
      For mission tracking, click here. For more information on NASA’s Scientific Balloon Program, visit: https://www.nasa.gov/scientificballoons.
      By Olivia Littleton
      NASA’s Wallops Flight Facility, Wallops Island, Va.
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      Last Updated Dec 10, 2024 EditorOlivia F. LittletonContactOlivia F. Littletonolivia.f.littleton@nasa.govLocationWallops Flight Facility Related Terms
      Scientific Balloons Astrophysics Astrophysics Division Goddard Space Flight Center Wallops Flight Facility Explore More
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    • By European Space Agency
      Video: 00:02:27 ESA’s Proba-3 mission lifted off on its PSLV-XL rocket from Satish Dhawan Space Centre in Sriharikota, India, on Thursday, 5 December, at 11:34 CET (10:34 GMT, 16:04 local time).
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