Christopher Karlgaard

NASA NTRS2022

Mars Entry Instrumentation Flight Data and Mars 2020 Entry Environments

On February 18th, 2021, the Mars 2020 entry vehicle delivered the Perseverance rover to the surface of Mars. The entry vehicle carried a set of instrumentation installed on the heatshield and backshell to measure aerodynamic and aerothermal performance, named the Mars Entry, Descent, and Landing Instrumentation 2. This set of instrumentation included pressure transducers, thermocouples, heatflux sensors, and a radiometer, as well as a dedicated sensor support electronics system. All MEDLI2 hardware operated as expected during cruise and entry. MEDLI2 sensors gathered accurate pressure measurements in hypersonic through supersonic regimes to reconstruct vehicle attitude and atmospheric profiles. MEDLI2 on the heatshield sensors indicated that surface temperatures, caused by turbulent heating beginning 70 seconds after entry, remained at or below 1430 °C, while heatshield bondline temperatures rose less than 45 °C. Backshell surface TPS temperatures peaked at 630 °C, which was caused primarily by radiative heating measured by several separate sensors. The MEDLI2 temperature and pressure measurements enabled further detailed characterization of the Mars 2020 entry performance, and the flight dataset will provide a wealth of information for the EDL community and future mission designers.

thermal protection system↗

NASA NTRSDate not supplied

Aerodynamic Performance of the 2018 InSight Mars Lander

InSight touched down in Elysium Planitia on 26 November 2018, becoming NASA’s eighth successful entry, descent, and landing (EDL) at Mars. InSight was a build-to-print of the successful 2008 Phoenix EDL system, flying a non-spinning, ballistic trajectory with a 70-degree sphere-cone aeroshell (2.65-meter diameter), disk-gap-band parachute, and pulsed terminal descent and landing engines. This work discusses entry aerodynamic performance for InSight up to parachute deployment, including pre-flight aerodynamics predictions and comparisons with post-flight reconstruction, as well as comparisons with the Phoenix reconstruction.

Ashley M Korzun↗

NASA NTRSDate not supplied

Post-flight Analysis of Atmospheric Properties from Mars 2020 Entry, Descent, and Landing

The Mars 2020 spacecraft landed the Perseverance rover and Ingenuity helicopter successfully in Jezero crater on Feb. 18, 2021. The entry, descent, and landing (EDL) sequence of the spacecraft largely leveraged the previous Mars Science Laboratory (MSL) mission. The atmospheric modeling approach for Mars 2020 was also borrowed from MSL, and consisted of utilizing two mesoscale atmospheric models of the landing site during the Martian season of landing, and using that data to create a statistical model of the pressure, density, temperature, and winds that Mars 2020 could have expected to encounter. Additionally, Mars 2020 contained an optical sensor - Landing Vision System (LVS) - that relied on taking pictures of the terrain, and was sensitive to the dust opacity of the atmosphere. This paper will briefly describe the pre-flight atmospheric models used for Mars 2020, but will focus on post-flight assessment of these models by comparing them to near-landing day orbiter sounder data and onboard atmospheric measurements. Suggestions for potential model changes will be also discussed.

Soumyo Dutta↗

NASA NTRSDate not supplied

Demonstration of Navigation Doppler Lidar Capabilities Onboard the First Commercial Lunar Lander

Landing on the Moon safely, softly, and precisely is still an extremely difficult task to achieve. Navigation Doppler Lidar (NDL) was designed to provide a solution to spaceflight landing vehicles in achieving this task. NDL is a high-performance, compact, and cost-effective velocity and altitude measurement instrument that has been developed, tested and improved over many years. Testing has now culminated with NDL’s successful operation on two spaceflight vehicles this year: Astrobotic’s Peregrine lunar lander and Intuitive Machines’ Odysseus lunar lander. Odysseus became the first U.S. vehicle to land successfully on the Moon since Apollo 17. The performance data obtained by NDL during the Intuitive Machines mission is exceptional, and this mission fully demonstrated NDL’s ability to produce critical velocity and altitude data for future robotic and human exploration missions to the Moon and other planetary bodies. This paper will give an overview of NDL briefly describing its history, architecture, and theory of operation. NDL’s system checkout on Astrobotic’s Peregrine lunar lander is then discussed followed by NDL’s performance during the Intuitive Machines Odysseus lunar lander mission. A description of how the data acquired by NDL is then used to perform trajectory reconstruction and animation is then provided. Finally, this paper concludes with potential uses of NDL’s acquired mission data to future applications.

Lunar Landing↗

NASA NTRSDate not supplied

Demonstration of Navigation Doppler Lidar Capabilities Onboard the First Commercial Lunar Lander

Landing on the Moon safely, softly, and precisely is still an extremely difficult task to achieve. Navigation Doppler Lidar (NDL) was designed to provide a solution to spaceflight landing vehicles in achieving this task. NDL is a high-performance, compact, and cost-effective velocity and altitude measurement instrument that has been developed, tested and improved over many years. Testing has now culminated with NDL’s successful operation on two spaceflight vehicles this year: Astrobotic’s Peregrine lunar lander and Intuitive Machines’ Odysseus lunar lander. Odysseus became the first U.S. vehicle to land successfully on the Moon since Apollo 17. The performance data obtained by NDL during the Intuitive Machines mission is exceptional, and this mission fully demonstrated NDL’s ability to produce critical velocity and altitude data for future robotic and human exploration missions to the Moon and other planetary bodies. This paper will give an overview of NDL briefly describing its history, architecture, and theory of operation. NDL’s system checkout on Astrobotic’s Peregrine lunar lander is then discussed followed by NDL’s performance during the Intuitive Machines Odysseus lunar lander mission. A description of how the data acquired by NDL is then used to perform trajectory reconstruction and animation is then provided. Finally, this paper concludes with potential uses of NDL’s acquired mission data to future applications.

Lunar Landing↗