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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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586 records · Page 33
All sourcesNASA NTRSDOE OSTI
NASA NTRS2014

Trajectory Design for the Transiting Exoplanet Survey Satellite

The Transiting Exoplanet Survey Satellite (TESS) is a National Aeronautics and Space Administration (NASA) mission, scheduled to be launched in 2017. TESS will travel in a highly eccentric orbit around Earth, with initial perigee radius near 17 Earth radii (Re) and apogee radius near 59 Re. The orbit period is near 2:1 resonance with the Moon, with apogee nearly 90 degrees out-of-phase with the Moon, in a configuration that has been shown to be operationally stable. TESS will execute phasing loops followed by a lunar flyby, with a final maneuver to achieve 2:1 resonance with the Moon. The goals of a resonant orbit with long-term stability, short eclipses and limited oscillations of perigee present significant challenges to the trajectory design. To rapidly assess launch opportunities, we adapted the Schematics Window Methodology (SWM76) launch window analysis tool to assess the TESS mission constraints. To understand the long-term dynamics of such a resonant orbit in the Earth-Moon system we employed Dynamical Systems Theory in the Circular Restricted 3-Body Problem (CR3BP). For precise trajectory analysis we use a high-fidelity model and multiple shooting in the General Mission Analysis Tool (GMAT) to optimize the maneuver delta-V and meet mission constraints. Finally we describe how the techniques we have developed can be applied to missions with similar requirements. Keywords: resonant orbit, stability, lunar flyby, phasing loops, trajectory optimization

Stationkeepting↗
NASA NTRS2014

Trajectory Design for the Transiting Exoplanet Survey Satellite (TESS)

The Transiting Exoplanet Survey Satellite (TESS) is a National Aeronautics and Space Administration (NASA) mission launching in 2017. TESS will travel in a highly eccentric orbit around Earth, with initial perigee radius near 17 Earth radii (Re) and apogee radius near 59 Re. The orbit period is near 2:1 resonance with the Moon, with apogee nearly 90 degrees out-of-phase with the Moon, in a configuration that has been shown to be operationally stable. TESS will execute phasing loops followed by a lunar flyby, with a final maneuver to achieve 2:1 resonance with the Moon. The goals of a resonant orbit with long-term stability, short eclipses and limited oscillations of perigee present significant challenges to the trajectory design. To rapidly assess launch opportunities, we adapted the SWM76 launch window tool to assess the TESS mission constraints. To understand the long-term dynamics of such a resonant orbit in the Earth-Moon system we employed Dynamical Systems Theory in the Circular Restricted 3-Body Problem (CR3BP). For precise trajectory analysis we use a high-fidelity model and multiple shooting in the General Mission Analysis Tool (GMAT) to optimize the maneuver delta-V and meet mission constraints. Finally we describe how the techniques we have developed can be applied to missions with similar requirements.

Monte Carlo↗
NASA NTRS2014

An Earth-Moon System Trajectory Design Reference Catalog

As demonstrated by ongoing concept designs and the recent ARTEMIS mission, there is, currently, significant interest in exploiting three-body dynamics in the design of trajectories for both robotic and human missions within the Earth-Moon system. The concept of an interactive and 'dynamic' catalog of potential solutions in the Earth-Moon system is explored within this paper and analyzed as a framework to guide trajectory design. Characterizing and compiling periodic and quasi-periodic solutions that exist in the circular restricted three-body problem may offer faster and more efficient strategies for orbit design, while also delivering innovative mission design parameters for further examination.

Libration Orbits↗
NASA NTRS2017

Preliminary Analysis of Ground-based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

Estimation↗
NASA NTRS2017

Preliminary Analysis of Ground-Based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations'' scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

Libration Point↗
NASA NTRS2019

Solar Radiation Pressure Effects on the Orbital Motion at SEL2 for the James Webb Space Telescope

Due to James Webb Space Telescope’s large sunshield, which will always be facing the Sun to protect the observatory’s instruments, Solar Radiation Pressure (SRP) has an important effect on its orbital motion around SEL2. Moreover, SRP is highly dependent on the observatory’s attitude with respect to the Sun observatory line. This paper explores the impact of SRP for different attitude profiles on the size of a reference orbit.

Libration Point Orbit↗
NASA NTRSDate not supplied

Massless Exploration – Humans as a Solar System Species

A vision for exploration of the solar system in an earth independent manner is presented taking into account key drivers, challenges and future technological advances. This work was in response to requirements set by the NASA Advanced Exploration Systems (AES) Office. Planetary targets, key assumptions and approaches to utilizing non-terrestrial resources are presented. The mission was divided into four sprints. The first sprint aims at a settlement on Earth’s moon. The second sprint aims at establishing a Lagrangian point station near the moon. The third sprint leads to the colonization of Mars and its moons. The fourth and final sprint investigated the exploration of Callisto, a moon of Jupiter. Bio-inspired approaches to technology and processes were considered to ensure that the in-space habitats are Earth like. The conclusion based on exploring the four sprints is that it is feasible to colonize the solar system without relying on earth but this relies on critical technology development and investments in emerging areas.

In-situ resource utilization↗
NASA NTRSDate not supplied

Massless Exploration: Humans as a Solar System Species

A vision for exploration of the solar system in an earth independent manner is presented taking into account key drivers, challenges and future technological advances. This work was in response to requirements set by the NASA Advanced Exploration Systems (AES) Office. Planetary targets, key assumptions and approaches to utilizing non-terrestrial resources are presented. The mission was divided into four sprints. The first sprint aims at a settlement on Earth’s moon. The second sprint aims at establishing a Lagrangian point station near the moon. The third sprint leads to the colonization of Mars and its moons. The fourth and final sprint investigated the exploration of Callisto, a moon of Jupiter.. Bio-inspired approaches to technology and processes were considered to ensure that the in-space habitats are Earth like. The conclusion based on exploring the four sprints is that it is feasible to colonize the solar system without relying on earth but this relies on critical technology development and investments in emerging areas.

In-situ resource utilization↗