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Lunar laser ranging data deposited in the National Space Science Data Center: Filtered observations for January - June 1972 and unfiltered photon detections for July - December 1972

The documentation to be used in conjunction with the filtered data deposited in the National Space Science Data Center is presented. The data was obtained during laser ranging operations between the McDonald Observatory and Apollo 11, 14, and 15 reflectors for the six months ending June 30, 1972. Unfiltered photon detections for the succeeding six months are also included in the system. Nominal coordinates for the laser ranging equipment are given and the calibration code for filtered data is shown. Data format using the CDC 6600 computer is described.

Mulholland, J. D.↗

Analysis of SETI data collected in the parasitic mode

A system for performing SETI observations continuously as part of non-SETI observations at a radio observatory is presented, and the analysis of results obtained by the parasitic system is discussed. The system, designated SERENDIP, is a real-time microprocessor-controlled spectrum analyzer with algorithms for performing statistical operations and recording those spectra with characteristics presumed to be typical of intelligent rather than astrophysical origin. Programs also exist for the post-acquisition analysis of signal autocorrelation, power spectra, time behavior and positional coordinates, and for a generalized cluster analysis to detect clusters of signal detections. In a recent run of 35 days, the SERENDIP system detected 4000 narrowband spectra exceeding a preset threshold, of which 98% were determined to be of instrumental origin. The remaining class of detections is also believed to be instrumental, although not as well organized as the first signals, and means are currently being sought for eliminating them.

Bowyer, S.↗

Three-dimensional perspective software for representation of digital imagery data

A generalized three dimensional perspective software capability was developed within the framework of a low cost computer oriented geographically based information system using the Earth Resources Laboratory Applications Software (ELAS) operating subsystem. This perspective software capability, developed primarily to support data display requirements at the NASA/NSTL Earth Resources Laboratory, provides a means of displaying three dimensional feature space object data in two dimensional picture plane coordinates and makes it possible to overlay different types of information on perspective drawings to better understand the relationship of physical features. An example topographic data base is constructed and is used as the basic input to the plotting module. Examples are shown which illustrate oblique viewing angles that convey spatial concepts and relationships represented by the topographic data planes.

Junkin, B. G.↗

Modulated beam injection from the Space Shuttle during magnetic conjunctions of STS 3 with the DE 1 satellite

An electron beam emitted from the Office of Space Sciences 1 pallet on STS 3 was pulsed with specially designed very low frequency (VLF) formats in an attempt to generate whistler mode waves. Modulated operations of the beam emitted by a fast pulse electron generator (FPEG) were initiated during times of magnetic conjunctions between STS 3 and the high-altitude DE 1 satellite equipped with broadband VLF receivers. Coordinated FPEG/VLF modulation and DE 1 wideband data acquisition were achieved in 12 different cases. No evidence of any waves generated by FPEG were detected on the DE 1 analog wideband data. However, it is shown that in all of the cases, either the STS 3 attitude was such that the emitted electrons struck the main body of the vehicle, or it was not possible for whistler mode waves to propagate from the STS 3 location up to the vicinity of the DE 1 satellite.

Inan, U. S.↗

Coherent phasing of segmented mirrors

The technical issues associated with a coherently phased segmented mirror can be divided into two types. The first involves the issues of manufacturing the surface quality of the mirror segments themselves (coherent phasing of individual segments). The second involves assembly issues of initializing in 1 G and retaining in 0 G an aggregate segmented mirror (coherent phasing between individual segments). Using a rectangular coordinate system at the vertex of a mirror segment, the rigid body motions are the six translational and rotational degrees of freedom. A first cut primary mirror wavefront error budget is presented. For a minimum operational wavelength of 30 micrometers, the derived values from the budget are: segment surface quality (0.45 micrometers RMS), radius mismatch (50 PPM), segment piston error (1.3 micrometers, segment tip/tilt error (0.6 microrad). Either active or passive segmented mirrors can be addressed, but if the surface quality of the off-axis segment and the radius matching requirements can be passively met, then only segment alignment need be sensed and controlled during operation in orbit. For the active mirror case, dimensional stability of the mirror material during operation is a key factor in establishing the degree of active figure control required.

Jones, Peter A.↗

Space Shuttle orbiter modifications to support Space Station Freedom

The Space Shuttle will be the primary vehicle to support the launch, assembly, and maintenance of the Space Station Freedom (SSF). In order to accommodate this function, the Space Shuttle orbiter will require significant modifications. These modifications are currently in development in the Space Shuttle Program. The requirements for the planned modifications to the Space Shuttle orbiter are dependent on the design of the SSF. Therefore, extensive coordination is required with the Space Station Freedom Program (SSFP) in order to identify requirements and resolve integration issues. This paper describes the modifications to the Space Shuttle orbiter required to support SSF assembly and operations.

Segert, Randall↗

Synergism of MODIS Aerosol Remote Sensing from Terra and Aqua

The MODerate-resolution Imaging Spectro-radiometer (MODIS) sensors, aboard the Earth Observing System (EOS) Terra and Aqua satellites, are showing excellent competence at measuring the global distribution and properties of aerosols. Terra and Aqua were launched on December 18, 1999 and May 4, 2002 respectively, with daytime equator crossing times of approximately 10:30 am and 1:30 pm respectively. Several aerosol parameters are retrieved at 10-km spatial resolution from MODIS daytime data over land and ocean surfaces. The parameters retrieved include: aerosol optical thickness (AOT) at 0.47, 0.55 and 0.66 micron wavelengths over land, and at 0.47, 0.55, 0.66, 0.87, 1.2, 1.6, and 2.1 microns over ocean; Angstrom exponent over land and ocean; and effective radii, and the proportion of AOT contributed by the small mode aerosols over ocean. Since the beginning of its operation, the quality of Terra-MODIS aerosol products (especially AOT) have been evaluated periodically by cross-correlation with equivalent data sets acquired by ground-based (and occasionally also airborne) sunphotometers, particularly those coordinated within the framework of the AErosol Robotic NETwork (AERONET). Terra-MODIS AOT data have been found to meet or exceed pre-launch accuracy expectations, and have been applied to various studies dealing with local, regional, and global aerosol monitoring. The results of these Terra-MODIS aerosol data validation efforts and studies have been reported in several scientific papers and conferences. Although Aqua-MODIS is still young, it is already yielding formidable aerosol data products, which are also subjected to careful periodic evaluation similar to that implemented for the Terra-MODIS products. This paper presents results of validation of Aqua-MODIS aerosol products with AERONET, as well as comparative evaluation against corresponding Terra-MODIS data. In addition, we show interesting independent and synergistic applications of MODIS aerosol data from both Terra and Aqua. In certain situations, this combined analysis of Terra- and Aqua-MODIS data offers an insight into the diurnal cycle of aerosol loading.

Ichoku, Charles↗

EUNIS-07: First Look

The Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket instrument is a two-channel imaging spectrograph that observes the solar corona with high spectral resolution and a rapid cadence made possible by unprecedented sensitivity. EUNIS flew for the first time on 2006 April 12 (EUNIS-06), returning over 140 science exposures at a cadence of 2.1 s; each exposure comprises six 1K x 1K active pixel sensor (APS) images, three for each wavelength channel (170-205 $\AA$ and 300-370 $\AA$). Analysis of EUNIS-06 data has so far shed new light on the nature of coronal bright points, cool transients, and coronal loop arcades and has enabled calibration updates for TRACE and SOHO's CDS and EIT. EUNIS flew successfully again on 2007 November 6 (EUNIS-07). Because the APS's were operated in video rather than snapshot mode, a faster cadence of 1.3 s was possible (97% duty cycle), resulting in 276 science exposures. We present an overview of the EUNIS-07 spectra and describe the coordinated observing program executed by the Hinode Extreme ultraviolet Imaging Spectrograph (EIS) that will, in conjunction with the absolute radiometric calibration of EUNIS-07, result in the first on-orbit radiometric calibration of EIS. EUNIS data are freely available to the solar physics community. EUNIS is supported by the NASA Heliophysics Division through its Low Cost Access to Space Program in Solar and Heliospheric Physics.

Rabin, Douglas M.↗

Eurasian Reindeer Pastoralism in a Changing Climate: Indigenous Knowledge and NASA Remote Sensing

It is intended that Reindeer Mapper/EALAT will be able to provide reindeer herders with an efficient tool for managing the real-time movements and migrations of their herds through enabling improved efficiency in linking different members of the herder settlements or communities and providing real-time local, satellite or other data (e.g., ice melt in lakes and rivers, weather events), thus enabling real time adjustments to herd movements to avoid problems such as changing weather/climate conditions, freeze-thaw "lock-out" problems, or take advantage of availability of better pasturelands along migration routes. The system is being designed to incorporate local data to allow users to bring their own data into the system for analysis in addition to the data provided by the system itself. With the local information of the population, up to date environmental data and habitat characteristics, the system could generate maps depicting important features of interest for reindeer managers. One of the products derived from the planned Reindeer Mapper system will be a web-based graphic display that allows analysts to quickly pinpoint areas of interest such as those with large concentrations of reindeer and provide surrounding environmental information. The system could be automatically updated with near-real-time information such as hourly precipitation and snowfall rate and accumulation, daily surface and air temperatures, and vegetation cover conditions. The system could bring attention to the proximity of human and animal populations as part of the need for control response. A local GIS will bring these many layers together with several supporting models, showing only a straightforward graphic of the real-time situation in the field. Because the system proposed will be operating in the Internet environment, it should be virtually accessible from any network computers and wireless remote access from the field. The International Center for Reindeer Husbandry in Kautokeino, Norway, is providing regional and international coordination of and access to data sets and expertise, and will act as overall clearinghouse for EALAT information.

Maynard, N. G.↗

Adaptive Effects on Locomotion Performance Following Exposure to a Rotating Virtual Environment

During long-duration spaceflight, astronauts experience alterations in vestibular and somatosensory cues that result in adaptive disturbances in balance and coordination upon return to Earth. These changes can pose a risk to crew safety and to mission objectives if nominal or emergency vehicle egress is required immediately following long-duration spaceflight. At present, no operational countermeasure is available to mitigate the adaptive sensorimotor component underlying the locomotor disturbances that occur after spaceflight. Therefore, the goal of this study is to develop an inflight training regimen that facilitates recovery of locomotor function after long-duration spaceflight. The countermeasure we are proposing is based on the concept of adaptive generalization. During this type of training the subject gains experience producing the appropriate adaptive motor behavior under a variety of sensory conditions and response constraints. As a result of this training a subject learns to solve a class of motor problems, rather than a specific motor solution to one problem, i.e., the subject learns response generalizability or the ability to "learn to learn." under a variety of environmental constraints. We are developing an inflight countermeasure built around treadmill exercise activities. By manipulating the sensory conditions of exercise by varying visual flow patterns, body load and speed we will systematically and repeatedly promote adaptive change in locomotor behavior. It has been shown that variable practice training increases adaptability to novel visuo-motor situations. While walking over ground in a stereoscopic virtual environment that oscillated in roll, subjects have shown compensatory torso rotation in the direction of scene rotation that resulted in positional variation away from a desired linear path. Thus, postural sway and locomotor stability in 1-g can be modulated by visual flow patterns and used during inflight treadmill training to promote adaptive generalization. The purpose of this study was to determine if adaptive modification in locomotor performance could be achieved by viewing simulated self-motion in a passive-immersive virtual ' environment over a prolonged period during treadmill locomotion.

Mulavara, A. P.↗

Mars Express Forward Link Capabilities for the Mars Relay Operations Service (MaROS)

This software provides a new capability for landed Mars assets to perform forward link relay through the Mars Express (MEX) European Union orbital spacecraft. It solves the problem of standardizing the relay interface between lander missions and MEX. The Mars Operations Relay Service (MaROS) is intended as a central point for relay planning and post-pass analysis for all Mars landed and orbital assets. Through the first two phases of implementation, MaROS supports relay coordination through the Odyssey orbiter and the Mars Reconnaissance Orbiter (MRO). With this new software, MaROS now fully integrates the Mars Express spacecraft into the relay picture. This new software generates and manages a new set of file formats that allows for relay request to MEX for forward and return link relay, including the parameters specific to MEX. Existing MEX relay planning interactions were performed via email exchanges and point-to-point file transfers. By integrating MEX into MaROS, all transactions are managed by a centralized service for tracking and analysis. Additionally, all lander missions have a single, shared interface with MEX and do not have to integrate on a mission-by mission basis. Relay is a critical element of Mars lander data management. Landed assets depend largely upon orbital relay for data delivery, which can be impacted by the availability and health of each orbiter in the network. At any time, an issue may occur to prevent relay. For this reason, it is imperative that all possible orbital assets be integrated into the overall relay picture.

Allard, Daniel A.↗

Airspace Technology Demonstration 3 (ATD-3): Multi-Flight Common Route (MFCR) Technology Transfer Document Summary Version 1.0

This summary document and accompanying technology artifacts satisfy the second of three Research Transition Products (RTPs) defined in the ATD-3 Applied Traffic Flow Management (ATFM) Research Transition Team (RTT) Plan. This transfer consists of NASA's Multi-Flight Common Route (MFCR) research for efficient route corrections for en-route weather avoidance. The MFCR concept builds on the experience of the legacy Dynamic Weather Routes (DWR) and focuses on a better balance of potential savings with ATC acceptability, common route corrections options for multiple flights on similar routings, and better use of existing and/or modern automation for communication and coordination of route change options. All of these capabilities are expected to improve system performance significantly in terms of actual delay-reducing clearances issued to flights compared to that of the DWR tool and operating concept.

tech transfer↗

Using Systems Engineering to Develop an Integrated Crew Health and Performance System to Mitigate Risk for Human Exploration Missions

New space exploration missions are currently being designed to take humanity beyond low Earth orbit (LEO) to cis-lunar space, the lunar surface, and eventually to Mars. These missions carry increased risks due to a number of factors, including distance from Earth, exposure to deep space hazards, reduced capacity and ability to resupply and evacuate, and increased communication delays. As distance from Earth grows and mission length increases, a growing proportion of mission risk can be attributed to the “human system.” Almost twenty years ago, the Institute of Medicine in the United States recommended the early and complete integration of the human system into the spacecraft and mission design process to mitigate this increased risk inherent in exploration missions. Exploration missions will require increasing levels of crew self-sufficiency that will challenge the current operational paradigms established in LEO. Enabling progressive Earth independence requires management of the increasingly complex interactions among spacecraft systems and integration of all the data and functions that affect human health and performance into one coordinated system –the Crew Health and Performance (CHP) system. This system is a critical spacecraft system that is analogous to other systems such as propulsion, guidance and navigation, or avionics. Design and integration of the CHP system requires the evidence-based merger of typically disparate disciplines such as medicine, human factors, and life support system design, using systems engineering (SE) practices. SE provides traceability of spacecraft requirements and enables reliable and repeatable trade space analysis of the many competing options for hardware and software to be included in the mission architecture. The approach described here enables spacecraft and mission designers to align the scope of a CHP system with mission specific requirements, decrease risk to the crew, and increase the probability of mission success.

Kerry McGuire↗

The Search for Chiral Asymmetry as a Potential Biosignature in Samples from Mars

The search for evidence of extraterrestrial life in our solar system is currently guided by our understanding of terrestrial biology and its associated biosignatures. The observed homochirality in all life on Earth, that is, the predominance of “left-handed” or L-amino acids and “right-handed” or D-sugars, is a unique property of life that is crucial for molecular recognition, enzymatic function, information storage and structure and is thought to be a prerequisite for the origin or early evolution of life. Therefore, the detection of L- or D-enantiomeric excesses of chiral amino acids and sugars could be a powerful indicator of extant or extinct life on Mars or other habitable environments in our solar system. The exploration of habitable environments on Mars, including an assessment of the preservation potential for complex organics of either abiotic or biological origin, remains a key goal of both current and future Mars missions. Now with the unambiguous detection of indigenous organic matter in sedimentary rocks on Mars [1-3], NASA’s Curiosity rover has significantly advanced our understanding of the preservation of potential chemical biosignatures in the martian near surface. Although amino acids have not yet been identified by in situ measurements on Mars, if they were present, it is expected that amino acid hydrolysis and racemization would be very slow and any chiral or isotopic signatures from an extinct martian biota could be preserved for billions of years, given the extremely cold and dry surface conditions [4]. One of ESA’s Rosalind Franklin rover payload instruments called the Mars Organic Molecule Analyzer (MOMA) includes a wet chemistry package capable of measuring the enantiomeric ratios of any chiral amino acids present at part-per-million concentrations or higher [5]. The complexity and limited duration of spaceflight operations and the known analytical challenges associated with in situ extraction and characterization of trace reduced organic compounds in ancient rocks make it challenging to determine the origins of martian organic matter found to date. Coordinated state-of-the-art laboratory measurements of returned samples from Mars that include spatially resolved chemical, mineralogical, and isotopic studies and molecule-specific isotopic and enantiomeric measurements will be required to firmly establish whether the complex organic matter detected on Mars comes from biotic or abiotic sources. Ultimately, sample return may be our best chance of identifying chemical biosignatures from a past or present martian biota, if one ever existed on Mars. NASA’s Perseverance rover will collect dozens of surface sample cores for possible future return to Earth by NASA and ESA. Here we review our current knowledge of the distributions and enantiomeric and isotopic compositions of non-biological amino acids found in meteorites compared to terrestrial biochemistry and propose a set of measurement criteria that should be used to help establish the origin of any chiral asymmetry detected in samples from Mars [6].

Daniel P Glavin↗

Communications with Curiosity during solar conjunction

This study examines the methodology for operating and communicating with NASA's Curiosity Rover (MSL) during the 2019 solar conjunction. For MSL, solar conjunction occurs when the viewing angle between the Sun and Mars from Earth's perspective falls below 3 degrees, which occurs roughly every two Earth years and lasts for about two weeks. This presents a challenge for engineers operating a vehicle on Mars because the degraded signal to noise ratio disrupts data flow between Earth and the spacecraft. As a result, operators designate a command moratorium in which no commands are sent to the rover and instead design long-term plans that are uplinked weeks in advance (rather than the nominal case of daily uplinks). Coordinating communications with the rover leading up to and following conjunction requires negotiations with several orbiters, another lander, and the Deep Space Network (DSN) each with their own set of constraints. It is the Strategic Comm Planning T coordination, which acts as a baseline for the conjunction Comm team faced additional complications such as the arrival of two new spacecraft at Mars - Roscosmos ExoMars Trace Gas Orbiter (TGO).

Laubach, Sharon↗

NASA’s Secured Airspace for Urban Air Mobility (UAM)

The Urban Air Mobility (UAM) architecture is leveraged from the Unmanned Traffic Management (UTM) concept of operations. Within the UAM environment, UAM operators work collaboratively to manage aerial vehicles in the urban environment. Providers of Services for UAM (PSU), UAM operators, and Supplemental Data Service Providers (SDSP) provide services to support flight operations within that environment. As a recognized need, various views of UAM flight information are provided to the public and public safety entities. To accomplish this, among other goals, the Federal Aviation Administration (FAA) can coordinate flight information between the FAA controlled National Airspace System (NAS) and the UAM environments through the FAA-Industry Data Exchange Protocol (FIDXP). This concept of UAM proposes to develop short-range, point-to-point transportation systems in metropolitan areas using vertical take-off and landing (VTOL) or short take-off and landing (STOL) aircraft to overcome increasing surface congestion. To garner the support of UAM and to realize its potential, an assurance of cybersecurity is critical for public acceptance. Understanding the various components communicating with one-another cybersecurity, like in other industries, has come to the forefront highlighting the need to protect these networks and systems from cyberattacks. With the planned growth and reach of UAM systems, it’s clear that the associated data exchange and service interactions will be at risk due to numerous types of cybersecurity attacks. Consequently, as these threats evolve, the UAM cybersecurity capabilities must adapt to these changes as well. While learning is always the goal, the overall intent of this workshop is to make recommendations on the following: (1) how future UAM environments can be protected against cyber-attacks, and (2) what mechanisms should be put in place to detect attacks against UAM environments.

UAM↗

Earth Observations to Assess Impact of Hurricane Katrina on John C. Stennis Space Center

The peril from hurricanes to Space Operations Centers is real and is forecast to continue; Katrina, Rita, and Wilma of 2005 and Charley, Frances, Ivan, and Jeanne of 2004 are sufficient motivation for NASA to develop a multi-Center plan for preparedness and response. As was demonstrated at SSC (Stennis Space Center) in response to Hurricane Katrina, NASA Centers are efficiently activated as local command centers, playing host to Federal and State agencies and first responders to coordinate and provide evacuation, relocation, response, and recovery activities. Remote sensing decision support provides critical insight for managing NASA infrastructure and for assisting Center decision makers. Managers require geospatial information to manage the federal city. Immediately following Katrina, SSC s power and network connections were disabled, hardware was inoperative, technical staff was displaced and/or out of contact, and graphical decision support tools were non-existent or less than fully effective. Despite this circumstance, SSC EOC (Emergency Operations Center) implemented response operations to assess damage and to activate recovery plans. To assist Center Managers, the NASA ASP (Applied Sciences Program) made its archive of high-resolution data over the site available. In the weeks and months after the immediate crisis, NASA supplemented this data with high-resolution, post-Katrina imagery over SSC and much of the affected coastal areas. Much of the high-resolution imagery was made available through the Department of Defense Clear View contract and was distributed through U.S. Geological Survey Center for Earth Resources Observation and Science "Hurricane Katrina Disaster Response" Web site. By integrating multiple image data types with other information sources, ASP applied an all-source solutions approach to develop decision support tools that enabled managers to respond to critical issues, such as expedient access to infrastructure and deployment of resources, provision of temporary shelter, logistical control of critical supplies, and the mobilization and coordination of assets from ground crews to aircraft/airspace management. Furthermore, ASP developed information products that illustrate risks to SSC's infrastructure from surge, inundation, and flood. Current plans include developing wind-risk prototype products for refinement and adoption into EOC plans.

Graham, William D.↗

Global Precipitation Measurement (GPM) and International Space Station (ISS) Coordination for CubeSat Deployments to Minimize Collision Risk

The Global Precipitation Measurement Mission (GPM) is a joint U.S. and Japan mission to observe global precipitation, extending the Tropical Rainfall Measuring Mission (TRMM), which was launched by H-IIA from Tanegashima in Japan on February 28TH, 2014 directly into its 407km operational orbit. The International Space Station (ISS) is an international human research facility operated jointly by Russia and the USA from NASA's Johnson Space Center (JSC) in Houston Texas. Mission priorities lowered the operating altitude of ISS from 415km to 400km in early 2105, effectively placing both vehicles into the same orbital regime. The ISS has begun a program of deployments of cost effective CubeSats from the ISS that allow testing and validation of new technologies. With a major new asset flying at the same effective altitude as the ISS, CubeSat deployments became a serious threat to GPM and therefore a significant indirect threat to the ISS. This paper describes the specific problem of collision threat to GPM and risk to ISS CubeSat deployment and the process that was implemented to keep both missions safe from collision and maximize their project goals.

Pawloski, James H.↗