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Young, Brian

Publications and source records attributed to Young, Brian.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2021

Maven Navigation Support of the Mars 2020 Perseverance Entry, Descent and Landing

Through three years of maneuvering, the MAVEN orbiter was able to support the Mars 2020 (M2020) Perseverance Entry, Descent and Landing (EDL), while also changing to a more relay friendly orbit and preserving a mission lifetime through 2030. The synchronization of the MAVEN orbit for M2020 EDL will be reviewed, followed by a description of the MAVEN phasing for EDL. Poten-tial concerns that arose from large density variations will be discussed, along with the interfaces between MAVEN and M2020.

Kangas, Julie↗
NASA NTRS2020

Navigation Design and Operations of Maven Aerobraking

This paper describes the operational design and execution of the MAVEN aerobraking phase at Mars from a Navigation Team perspective. MAVEN was designed to perform atmospheric science in a ~150x6200 km altitude elliptical orbit. After the primary science mission, it was decided that MAVEN should circularize its orbit, as much as feasible from a spacecraft and mission standpoint, to better support relay operations with the landers. As a result, MAVEN performed aerobraking in the first half of 2019 to reduce its orbit to ~150x4500 km altitude. Although MAVEN did not decrease its altitude as low as previous aerobraking missions, it had several unique challenges. Science observations continued to be taken during aerobraking, requiring dramatically better Navigation accuracies than typical for such phases. Furthermore, continuous DSN coverage with 2-way Doppler data was not available. So, with 40% less Doppler data, Navigation had to meet prediction accuracies which were an order of magnitude smaller than in previous aerobraking operations. Spacecraft accelerometer data was included in Navigation analyses in order to meet these requirements.

Jakosky, Bruce↗
NASA NTRS2019

Navigating MarCO, the first interplanetary CubeSats

The NASA’s Mars Cube One (MarCO) probes are twin 6U CubeSats that were launched into space on May 5, 2018. The MarCOs shared a launch vehicle with NASA’s InSight mission, separating from the Atlas V Centaur upper stage after InSight. The MarCOs were injected into an Earth-Mars transfer trajectory and were independently navigated to the proximity of Mars. On 26 November, 2018 the MarCO probes flew by Mars as the InSight lander descended to the surface, providing real-time relay of InSight UHF data back to the Earth. This paper describes the approaches used to design the MarCOs’ trajectories and to navigate them to Mars, presenting the challenges of navigating and operating CubeSats in deep space, and the technological firsts achieved by the MarCO mission.

Young, Brian↗
NASA NTRS2019

Using telemetry to navigate the MarCO cubesats to Mars

The two MarCO “cubesat” spacecraft were launched alongside NASA’s InSight in May 2018, operating primarily as a technology demonstrator for small satellites in deep space, with a nominal (but experimental) mission to provide relay support for the primary spacecraft during entry, descent, and landing at Mars. Due to their small size and experimental nature, extensive use of telemetry beyond that commonly used by deep space missions was necessary to complete adequate orbit determination. In particular, telemetry was valuable in two areas: use of wheel speeds during thruster calibrations to improve knowledge of individual thruster force levels, and the use of propellant temperature and pressure data to correctly model small thrusting events on board the vehicle.

Martin-Mur, Tomas↗
NASA NTRS2019

Aerobracking the ExoMars TGO: the JPL Navigation Experience

In October 2016, ESA’s Trace Gas Orbiter entered into orbit around Mars. The transfer from its initial 24-hour elliptical orbit into the final 2-hour science orbit was helped by means of 952 aerobraking passes between March 2017 and February 2018. For this first aerobraking operation by European Space Operations Centre (ESOC), a dedicated partnership was organized between ESOC and NASA’s Jet Propulsion Laboratory (JPL) to allow for JPL navigation team’s support during the TGO aerobraking operations. The Mission Design and Navigation section at JPL supported the mission by providing consulting in aerobraking navigation operations and independent orbit determination solutions during TGO’s aerobraking. This paper discusses the JPL Navigation team’s experience, challenges faced, and lessons learned during TGO’s aerobraking at Mars. Topics include the collaboration between the two navigation teams, configuration of orbit determination for aero drag passes, arrangement of automated orbit determination, and reporting processes.

Young, Brian↗
NASA NTRS2019

Orbit determination sensitivity analysis for th Europa Clipper Mission tour

This paper will assess the sensitivity of OD delivery and knowledge performance for the current Europa Mission trajectory through parametric variation of a baseline tour navigation strategy.2 Variations of several parameters are run, one at a time, to determine the impact on spacecraft ephemeris uncertainties at OD knowledge, delivery, and encounter reconstruction times. There are two basic categories of sensitivity runs considered: variations of tracking data type and amount, and variations to dynamic parameters. The results of these parameter and data variations are compared against the values necessary to achieve accurate instrument pointing and observation planning.

Young, Brian↗
NASA NTRS2018

Practical Orbit Determination for Aerobraking with Accumulated Accelerometer Data

Navigation during aerobraking missions has historically relied solely on radiometric Doppler data. Accelerometer data, available on all modern spacecraft, has the potential to supplement Doppler data, increasing operational tempos, filling tracking data gaps, and improving the accuracy of orbit determination solutions. However, integration of Doppler and accelerometer data into the batch filter solutions used for operational navigation has proven to be practically challenging, due to the narrow region of adequate linear approximation for acceleration incurred by drag. This work proposes to use the accumulated velocity changes derived from these values as a more compatible data type. Demonstrations of results focus on NASA’s Maven and ESA’s TGO mission, and how this technique can be used to improve operations for the upcoming Maven aerobraking phase with reduced tracking data and lighter staffing requirements.

Young, Brian↗
NASA NTRS2017

JPL Navigation Support for the JAXA Akatsuki (Planet-C) Return to Venus

This paper details the orbit determination activities undertaken at JPL in support of the Akatsuki (a.k.a. Planet-C) mission’s return to Venus. The JPL navigation team’s role was to provide independent navigation support as a point of comparison with the JAXA generated orbit determination solutions. Topics covered will include a mission and spacecraft overview; small forces modeling; cruise, approach, and Venus phase orbit determination results; and the international teaming arrangement. A discussion of the preparations for the Venus orbit insertion maneuver, which was successfully executed on December 7, 2015, is also covered in detail in the paper.

Young, Brian↗
NASA NTRS2016

MAVEN Transition-To-Science Maneuvers and Comet Siding Spring

After the September 2014 arrival of the Mars Atmosphere Volatile Evolution mission (MAVEN) at Mars, the spacecraft was to perform five maneuvers to reduce the orbit period from 35 to 4.5 hours, and lower the periapsis altitude into the target in-situ science density corridor. While in route, however, the potential threat — and science opportunity — from Comet C/2013 Siding Spring crystallized, and the plan had to be modified to shield the spacecraft behind Mars and support new observations. This paper describes the plan modifications, Monte Carlo analyses necessary to ensure success, and results of executing the modified plan.

Young, Brian↗
NASA NTRS2016

MAVEN Navigation During the First Mars Year of the Science Mission

The Mars Atmosphere and Volatile Evolution mission (MAVEN) is the first mission devoted to studying the Martian atmosphere. From a Navigation perspective it is unique in that science is performed at near aerobraking altitudes. This results in the requirements on Navigation trajectory accuracy requirements which are an order of magnitude tighter than those of aerobraking phases on previous missions. Navigation experiences with the Mars atmosphere are described as they pertain to Navigation models, trajectory reconstructions, trajectory predictions, density corridor control, and collision avoidance of other bodies around Mars.

Demcak, Stuart↗