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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS2023

Recurrent 3he-Rich Solar Energetic Particle Injections Observed By Solar Orbiter at ∼0.5 Au

We report Solar Orbiter observations of six recurrent solar energetic particle injections in 2022 March 3−6 at ∼0.5 au. All but one were associated with jets emanating from a plage near a large sunspot in active region 12 957. We saw large jets in injections with high 3He and Fe enrichments and minor jets in injections with no or lower enrichments. Furthermore, the event with the highest enrichment showed a more compact configuration of the underlying photospheric magnetic field. The higher fluences as well as harder spectra were seen in the event with a simultaneous jet and wider eruption. However, in this case, the energy buildup time in the source might be required to produce such spectra. Extreme-ultraviolet images from Solar Orbiter revealed a number of intersecting loops at the base of jets not seen from 1 au that might be a precondition for the recurrent events.

Sun: particle emission↗
NASA NTRS1996

Global Geospace Science/Polar Plasma Laboratory: POLAR

The Global Geospace Science (GGS) Project is discussed as part of the International Solar-Terrestrial Physics (ISTP) Science Initiative. The objectives of Polar Plasma Laboratory (POLAR), one of the two spacecraft to be used by the Project to fill critical gaps in the scientific understanding of solar and plasma physics, are outlined. POLAR Laboratory is described, along with POLAR instrumentation, support subsystems, and orbits. Launch vehicle and injection into orbit are also addressed.

Source record↗
NASA NTRS1981

Low cost transfer into useful sun-synchronous orbits at Mars

Mars oblateness has been found to provide sun-synchronous orbits, including orbits with stationary apsides, similar to those used at earth. A low mass and low data rate complement of scientific instruments placed in such orbits can provide exciting planetary investigations such as the Mars Orbiter Water Mission described herein. Use of a modest Shuttle kickstage (PAM-A) and existing spacecraft hardware makes this mission low-cost. A preliminary mission and spacecraft design is described. The major emphasis of the paper is on the mechanics of heliocentric transfer for the 1986 and 1988 launch opportunities, Martian sun-synchronous orbit geometries, injectable mass capabilities, and methods of achieving these scientifically useful orbits.

Glickman, R. E.↗
NASA NTRS2015

Seasonal Variations of the James Webb Space Telescope Orbital Dynamics

LV separation state is fixed ECEF, so inertial states vary with hourly, daily, monthly, and yearly frequencies The net effect of all frequencies leads to significant variations in orbit geometry Injection states can be matched with invariant manifolds of periodic orbits in the CR3BP to explain observed final orbit.

Three Body Problem↗
NASA NTRS1978

Operational modes for a wave injection facility aboard spacelab and a sub-satellite

Various modes of operation are described for an orbiting wave injection facility planned to measure the properties of waves propagating in space plasma. Such a facility would cover a wide frequency range including MF and HF. Phase shift and Doppler shift measurements will yield more accurate measurements of echo time delay and the angle of arrival. Because Spacelab will involve some sub-satellites, some consideration is given to propagation between two vehicles both at HF and VHF.

Dyson, P. L.↗
NASA NTRSDate not supplied

Space Launch System Launch Windows and Day of Launch Processes

Lunar missions benefit from varying the launch azimuth as a function of launch time to allow longer launch windows with minimum performance impacts. This variable azimuth approach allows the vehicle to track the Moon’s apparent motion due to Earth’s rotation. The Space Launch System (SLS) Block 1 vehicle design requires the mission to launch into an elliptical parking orbit to provide sufficient energy to insert Orion into a Trans-Lunar Injection (TLI) orbit. The primary benefit of varying the launch azimuth, and as a result the achieved orbit inclination, allows the SLS Interim Cryogenic Propulsion Stage (ICPS) to perform its TLI burn closer to perigee and take advantage of performing a burn in a location where the burn will optimally raise apogee.

launch window↗
NASA NTRS1981

Study of certain launching techniques using long orbiting tethers

A study of the basic equations governing orbital transfers using long orbiting tethers is presented. A very simple approximation to the general transfer equation is derived for the case of short tethers and low eccentricity orbits. Numerical examples are calculated for the case of injection into a circular orbit from a platform in eccentric orbit and injection into eccentric orbit from a platform in circular orbit. For the case of long tethers, a method is derived for reducing tether mass and increasing payload mass by tapering the tether to maintain constant stress per unit of tether cross section. Formulas are presented for calculating the equilibrium orbital parameters taking into account the mass of the platform, tether, and payload.

Colombo, G.↗
NASA NTRS1998

An Overview of Mars Vicinity Transportation Concepts for a Human Mars Mission

To send a piloted mission to Mars, transportation systems must be developed for the Earth to Orbit, trans Mars injection (TMI), capture into Mars orbit, Mars descent, surface stay, Mars ascent, trans Earth injection (TEI), and Earth return phases. This paper presents a brief overview of the transportation systems for the Human Mars Mission (HMM) only in the vicinity of Mars. This includes: capture into Mars orbit, Mars descent, surface stay, and Mars ascent. Development of feasible mission scenarios now is important for identification of critical technology areas that must be developed to support future human missions. Although there is no funded human Mars mission today, architecture studies are focusing on missions traveling to Mars between 2011 and the early 2020's.

Dexter, Carol E.↗
NASA NTRS2018

PEG Enhancement for EM1 and EM2+ Missions

NASA is currently building the Space Launch System (SLS) Block-1 launch vehicle for the Exploration Mission 1 (EM-1) test flight. The next evolution of SLS, the Block-1B Exploration Mission 2 (EM-2), is currently being designed. The Block-1 and Block-1B vehicles will use the Powered Explicit Guidance (PEG) algorithm. Due to the relatively low thrust-to-weight ratio of the Exploration Upper Stage (EUS), certain enhancements to the Block-1 PEG algorithm are needed to perform Block-1B missions. In order to accommodate mission design for EM-2 and beyond, PEG has been significantly improved since its use on the Space Shuttle program. The current version of PEG has the ability to switch to different targets during Core Stage (CS) or EUS flight, and can automatically reconfigure for a single Engine Out (EO) scenario, loss of communication with the Launch Abort System (LAS), and Inertial Navigation System (INS) failure. The Thrust Factor (TF) algorithm uses measured state information in addition to a priori parameters, providing PEG with an improved estimate of propulsion information. This provides robustness against unknown or undetected engine failures. A loft parameter input allows LAS jettison while maximizing payload mass. The current PEG algorithm is now able to handle various classes of missions with burn arcs much longer than were seen in the shuttle program. These missions include targeting a circular LEO orbit with a low-thrust, long-burn-duration upper stage, targeting a highly eccentric Trans-Lunar Injection (TLI) orbit, targeting a disposal orbit using the low-thrust Reaction Control System (RCS), and targeting a hyperbolic orbit. This paper will describe the design and implementation of the TF algorithm, the strategy to handle EO in various flight regimes, algorithms to cover off-nominal conditions, and other enhancements to the Block-1 PEG algorithm. This paper illustrates challenges posed by the Block-1B vehicle, and results show that the improved PEG algorithm is capable for use on the SLS Block 1-B vehicle as part of the Guidance, Navigation, and Control System.

Von der Porten, Paul↗
NASA NTRS2006

Advances in Pharmacotherapeutics of Space Motion Sickness

Space Motion Sickness (SMS) is common occurrence in the U.S. manned space flight program and nearly 2/3 of Shuttle crewmembers experience SMS. Several drugs have been prescribed for therapeutic management of SMS. Typically, orally-administered SMS medications (scopolamine, promethazine) have poor bioavailability and often have detrimental neurocognitive side effects at recommended doses. Intramuscularly administered promethazine (PMZ) is perceived to have optimal efficacy with minimal side effects in space. However, intramuscular injections are painful and the sedating neurocognitive side effects of promethazine, significant in controlled ground testing, may be masked in orbit because injections are usually given prior to crew sleep. Currently, EVAs cannot be performed by symptomatic crew or prior to flight day three due to the lack of a consistently efficacious drug, concern about neurocognitive side effects, and because an in-suit vomiting episode is potentially fatal. NASA has long sought a fast acting, consistently effective anti-motion sickness medication which has only minor neurocognitive side effects. Development of intranasal formulations of scopolamine and promethazine, the two commonly used SMS drugs at NASA for both space and reduced gravity environment medical operations, appears to be a logical alternative to current treatment modalities for SMS. The advantages are expected to be fast absorption, reliable and high bioavailability, and probably reduced neurocognitive side effects owing to dose reduction. Results from clinical trials with intranasal scopolamine gel formulation and pre-clinical testing of a prototype microcapsule intranasal gel dosage form of PMZ (INPMZ) will be discussed. These formulations are expected to offer a dependable and effective noninvasive treatment option for SMS.

Putcha, Lakshmi↗
NASA NTRS2006

Aerocapture Technology Development for Planetary Science - Update

Within NASA's Science Mission Directorate is a technological program dedicated to improving the cost, mass, and trip time of future scientific missions throughout the Solar System. The In-Space Propulsion Technology (ISPT) Program, established in 2001, is charged with advancing propulsion systems used in space from Technology Readiness Level (TRL) 3 to TRL6, and with planning activities leading to flight readiness. The program's content has changed considerably since inception, as the program has refocused its priorities. One of the technologies that has remained in the ISPT portfolio through these changes is Aerocapture. Aerocapture is the use of a planetary body's atmosphere to slow a vehicle from hyperbolic velocity to a low-energy orbit suitable for science. Prospective use of this technology has repeatedly shown huge mass savings for missions of interest in planetary exploration, at Titan, Neptune, Venus, and Mars. With launch vehicle costs rising, these savings could be the key to mission viability. This paper provides an update on the current state of the Aerocapture technology development effort, summarizes some recent key findings, and highlights hardware developments that are ready for application to Aerocapture vehicles and entry probes alike. Description of Investments: The Aerocapture technology area within the ISPT program has utilized the expertise around NASA to perform Phase A-level studies of future missions, to identify technology gaps that need to be filled to achieve flight readiness. A 2002 study of the Titan Explorer mission concept showed that the combination of Aerocapture and a Solar Electric Propulsion system could deliver a lander and orbiter to Titan in half the time and on a smaller, less expensive launch vehicle, compared to a mission using chemical propulsion for the interplanetary injection and orbit insertion. The study also identified no component technology breakthroughs necessary to implement Aerocapture on such a mission. Similar studies of Aerocapture applications at Neptune, Venus, and Mars were studied in 2003 through 2005. All showed significant performance improvements for the missions studied. Findings from these studies were used to guide the technology development tasks originally solicited in a 2002 NASA ROSS Research Announcement. The tasks are now in their final year and have provided numerous improvements in modeling and hardware, for use in proposals or new mission starts. Major Accomplishments: Since validation of the Aerocapture maneuver requires a space flight, ground developments have focused on modeling and environment prediction, materials, and sensors. Lockheed Martin has designed and built a 2-meter Carbon-Carbon aeroshell "hot structure." The article utilizes co-cured stiffening ribs and advanced insulation to achieve large scale, and up to a 40% reduction in areal density over the Genesis probe construction. This concept would be an efficient solution for probes that experience heat rates near 800-1000 W/cm(exp 2), such as at Venus and Earth. Applied Research Associates has extensively tested a family of efficient ablative TPS materials that provide solutions for a range of heating conditions. These materials are being applied to high-temperature structures built by ATK Space Systems, led by Langley Research Center. One-meter aeroshells will be thermally tested to validate construction and demonstrate higher bondline temperatures, which can lead to mass savings of up to 30% over traditional heatshields. Ames Research Center has developed aeroshell instrumentation that could measure environmental conditions and material performance during atmospheric entry. Instruments to measure TPS recession, heat flux, and catalycity could be combined with traditional sensors to provide a "plug-and-play" system for minimal mass and power, that would acquire flight data for model improvement and risk reduction on future missions. Improved atmospheric and aerothermodynamic models ha also been a major focus of the program. Next Steps: Aerocapture is one of five technologies in competition for a flight validation opportunity through the New Millennium Program. If selected, a fully autonomous vehicle will perform an Aerocapture at Earth in 2010, and flight data will be used to validate the guidance system and the TPS material for science mission infusion.

Munk, Michelle M.↗
NASA NTRS2004

Coordination of Mars Orbiting Assets to Support Entry, Descent, and Landing (EDL) Activities

NASA policy requires continuous telecommunications with missions during the execution of their critical events, which implies constraints on where missions to other planets may land or inject into orbit. JPL is working to establish a telecommunications network at Mars to provide contact with inbound missions to Mars and assets that have landed on the Martian surface, thus reducing the constraints on where critical events may be performed. Coordination of network assets is required to cover an inbound mission's critical event, such as EDL. This paper describes the development of a tool to evaluate EDL coverage capability of Mars network assets over a specified launch date/arrival date space.

Mars Network↗