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Alan M Cassell

Publications and source records attributed to Alan M Cassell.

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2020

Aerocapture as an Enhancing Option for Ice Giants Missions

Investigation of Uranus and Neptune, via orbiter and atmospheric probes, is required to answer pressing science questions that have been raised in previous Decadal Surveys. As the Ice Giants are the farthest planets from Earth, traditional fully-propulsive orbit insertion missions would require a large amount of propellant, leaving less mass for the scientific payload; additionally, transit time to the planetary bodies near 13-15 years. Aerocapture uses aerodynamic forces generated by flight within a planetary atmosphere to decelerate and achieve orbit insertion. Although, aerocapture has not been used in the past, recent developments in thermal protection systems, guidance and control, and navigation capabilities enable the use of rigid, heritage entry vehicle configurations already flown at other planetary bodies for Ice Giants aerocapture. With the addition of these recent capabilities, aerocapture can robustly deliver spacecraft to Ice Giant orbits, while substantially increasing on-orbit payload mass (more than 40%) and reducing the transit time by 2-5 years (15-30%) relative to fully-propulsive orbit insertion.

Soumyo Dutta↗
NASA NTRSDate not supplied

Deployable Entry Vehicles for Future Science and Exploration Missions

Deployable Entry Vehicle (DEV) technology has made significant advances over the last decade with ground test development campaigns and flight test demonstrations. DEVs offer benefits over traditional rigid entry vehicles including lower volume and mass, while enabling larger payload delivery and greater landing access. A crucial mission benefit is the DEV capability to transform from a compactly stowed launch configuration to a high drag area entry system for delivery of landers, rovers, aerial platforms, and orbiters (via aerocapture). These benefits span the range of mission classes from Small Satellite to human-class exploration systems. This presentation will describe DEV technology development status, highlight mission concepts, and recommend future investments.

Mission Design↗
NASA NTRSDate not supplied

Small Spacecraft Sample Return Mission Concept to Support Gateway and Lunar Science

Sustaining long-term presence at the Moon will likely require innovative and cost-effective approaches for frequentand affordable payload return. NASA Ames Research Center and the Deep Space Logistics team at Kennedy SpaceCenter (which manages the Gateway Logistics Services missions) have investigated the development of a small spacecraft-based sample return capability to complement the limited sample return capacity available with the earlyOrion missions. The goal is to demonstrate a cost-effective capability as part of an early Deep Space Logisticsmission and provide up to 10 kg (~ 4 L volume) of scientific payload returned from the Gateway. The mission concept envisions the progressive addition of sample return capabilities, including returning temperature- andacceleration-sensitive payloads, and evolution into a commercially provided service, similar to existing International Space Station payload return logistics. An overview of payload science and technology use cases and smallspacecraft mission concepts will be presented to engage scientists, payload developers and mission planners who are considering lunar exploration activities that will require the return of high-value samples from the Gateway and/or the lunar surface.

Alan M Cassell↗
NASA NTRSDate not supplied

Trajectory Design for a Spacecraft Capable of Deploying Probes to the Martian Surface en Route to Low Mars Orbit

The presented trajectory design and analysis was performed for the Aeolus spacecraft mission concept. The Aeolus spacecraft consists of an orbiter (i.e., “mothership”) with the goal of transferring from Earth to low Mars orbit via propulsive and/or atmospheric braking (i.e., aerobraking). During various phases of flight from hyperbolic approach of Mars through low Mars Orbit, the Aeolus orbiter will deploy multiple probes which are targeted to land on the Martian surface with the goal of achieving global surface coverage.

Mars hyperbolic approach↗