The Lunar Thermal Mapper (LTM) instrument is a UK Space Agency funded infrared radiometer designed and built for the National Aeronautics and Space Administration Lunar Trailblazer mission launched in February 2025. LTM is a pushbroom imaging filter radiometer with 15 channels that cover the wavelength range from 6.25 to 100 mu m with a 40-70 m/pixel ground sampling. Lunar Trailblazer's mission is to understand the form, abundance and distribution of water across the lunar surface. LTM provides an independent measure of temperature to investigate thermal effects on water's mapped distribution as well as an independent measure of surface mineralogy. The LTM instrument's 15 infrared channels include four broadband temperature sensing channels (6.25-12.5, 12.5-25, 25-50 and 50-100 mu m) plus 11 additional narrow band (similar to 40 cm(-1)) filters from similar to 7-10 mu m to map and discriminate silicate composition. We review the LTM design and calibration campaign at the University of Oxford's Space Instrumentation facility and show that the instrument has sensitivity from 400 K with a Noise Equivalent Temperature Difference of <0.1 K to <1 K at 110 K for typical integration times (e.g., 30 Hz readout) from a nominal 70-130 km lunar orbit design altitude.

Active venting at the Aurora hydrothermal field was first located in 2014. In July 2023, the AUV/ROV Nereid Under Ice (NUI) expanded the known size of the Aurora hydrothermal field, discovering 7 ‘black smokers’ together with associated lower-temperature flow. In this study, we present a new high-resolution bathymetric map acquired from NUI which has allowed us to identify morphological features previously undetectable from ship multibeam. All known active vents are aligned along a single 230 m-long ridge, parallel to the Gakkel Ridge strike direction and intersected by a scarp following the general trend of the Lena Trough. The new vents were measured at up to 17 m height from 3D models generated using structure-from-motion techniques applied to opportunistically acquired imaging data collected while in exploration mode. The extent of extinct sulfides present, together with the towering height of vents are consistent with a period of sustained high-temperature venting at Aurora.

We report engineering results from 2023 under-ice fieldwork exploring the Aurora hydrothermal vent field with the hybrid remotely operated vehicle (HROV) Nereid Under Ice. The vehicle generated bathymetric maps, video, and 3D visual reconstructions of vent chimneys over 20 m in height, and collected samples, including the first low-temperature (125 degrees C) fluids collected from any vent field on the Gakkel Ridge. NUI's unique design enabled multi-modal operation (mapping, inspection, sampling), often as components of the same dive, while on the sea floor at 4000 m in the challenging conditions imposed by moving 9/10ths-10/10ths sea ice cover.

Internal structures of the Moon are key to understanding the origin and evolution of detected thousands of lunar seismic events and vastly improved our understanding of the Moon's interior. However, some critical questions like the state and composition of the core remain unsolved largely due to the sparsity of the Apollo seismic stations and the strong scattering of seismic waves in the top layer of the Moon. In this study, we propose the concept of a fiber seismic network on the Moon and discuss its potential in overcoming the challenges in imaging deep Moon structures. As an emerging technique, distributed acoustic sensing (DAS) can provide a cost-efficient solution for largeaperture and dense seismic network deployment in harsh environments. We compute lunar synthetic seismograms and evaluate the performance of DAS arrays of different configurations in retrieving the hidden core reflected seismic phase ScS from the strong scattered waves. We find that, compared to a sparse conventional seismic network, a fiber seismic network using tens of kilometers of cable can dramatically increase the chance of observing clear ScS by array stacking. Our results indicate that DAS could provide new opportunities for the future lunar seismic surveys, but more efforts and further evaluations are required to develop a space-proof DAS.

The MarCO mission, from initial concept through interplanetary flight operations, is a technological demonstration to advance technology necessary to bring NanoSpacecraft into deep space. While MarCO itself took advantage of the significant developments of INSPIRE, it pioneered operational usage and laid the groundwork for many NanoSpacecraft now in development. The remainder of this chapter will focus on the lessons learned from MarCO development and flight, including from the evolution of the design through early planning, integration and test, flight operations, and InSight entry-descent-and-landing support.

Selected in 2019 as a NASA SIMPLEx mission, Lunar Trailblazer is in implementation for flight system delivery at the end of 2022. The mission's goal is to understand the form, abundance, and distribution of water on the Moon and the lunar water cycle. Lunar Trailblazer also collects data of candidate landing sites to inform planning for future human and robotic exploration of the Moon and evaluate the potential for in situ resource utilization. Lunar Trailblazer's two science instruments, the High-resolution Volatiles and Minerals Moon Mapper (HVM3) and the Lunar Thermal Mapper (LTM) provide simultaneous high-resolution spectral imaging data to map OH/water, crustal composition, and thermophysical properties from a $100\pm 30$ km lunar polar orbit. The ∼210-kg flight system deploys from an ESPA Grande and utilizes a ∼1000 m/s $\Delta\mathrm{V}$ hydrazine chemical propulsion system, similar to that employed by GRAIL. Trailblazing elements include the novel state-of-the-art dataset collected at substantially reduced price point, fully geographically co-registered data products delivered to the Planetary Data System, planetary mission team demographics, Caltech campus mission operations, and student staffing of select mission ops roles. Lunar Trailblazer's pioneering development is providing key lessons learned for future planetary small spacecraft.

The launch and successful operation of the Mars Cube One (MarCO) CubeSats in May of 2018 ushered in a new era of solar system exploration. The 13 interplanetary CubeSats slated to fly on Artemis 1 in 2020 along with MarCO represent the beginning of a new paradigm of planetary exploration—one that utilizes the CubeSat form factor as both primary and supporting exploration platforms. Enabling technologies required by interplanetary CubeSats including relatively high Δv propulsion systems, capable high-frequency transponders, radiation-tolerant components, and extremely capable miniaturized science instruments are now becoming commercially available making these missions possible. Interplanetary CubeSats require different and more sophisticated spacecraft systems architectures and must utilize different and more sophisticated ground station systems than LEO missions. These differences are discussed in this chapter in detail, using specific examples from current and planned missions.

The Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport (InSight) spacecraft landed successfully on 26 November 2018 to conduct an exploration of the interior of Mars. To meet NASA's requirement for communications during critical events, the InSight lander transmitted telemetry continuously throughout entry, descent, and landing. This allowed the public to witness the landing in real time. The transmissions were received by five assets: three at Mars and two on Earth. These included real-time relay of telemetry by the first deep-space CubeSats. This paper describes the constraints on the design of an entry, design, and landing communication link; the uncertainties in the trajectory; and the modeling that was used to meet these constraints. It then reports on the actual performance of each link, including an unexpected degradation of signal to the Mars Reconnaissance Orbiter. The lessons learned from this process contributed to the successful relay of data from the Perseverance lander, as well as to the design of future landing communications systems.

This paper discusses recent activities at JPL that are focused on extending the Opportunistic Multiple Spacecraft Per Antenna (OMSPA) concept to include arraying multiple antennas. Specifically, we explore the ability to process multiple open loop recordings associated with multiple antennas and perform the appropriate alignment and combining. We focus on using the symbol stream combining technique and provide examples of performance measurements on actual spacecraft signals for MarCO A and B as well as the Mars Express.

Smallsats and cubesats have been suggested as low-cost alternative means to achieve scientific goals for interplanetary missions. On May 5, 2018, NASA launched the first interplanetary cubesat: Mars Cube One (MarCO). MarCO-A and MarCO-B are twin communications-relay cubesats designed to monitor InSight during its Entry, Descent and Landing (EDL) on November 26, 2018. After InSight's EDL, MarCO continued to flyby Mars and conduct a radio occultation of the planet. This is the first-ever radio occultation of a planet other than Earth performed, and also the first planetary science measurement taken by an interplanetary cubesat. This research presents a performance assessment of the MarCO radio science measurements, results of MarCO radio occultation task, and the expected radio science capability of MarCO-like cubesat. Future interplanetary radio science missions can investigate planetary atmospheres, ionospheres, and rings using radio occultation measurements; probe the interior of a planetary body with gravity measurements; and surface characteristics with bistatic scattering. Observations made by tracking MarCO from NASA's Deep Space Network using an open-loop recordings of the X-band radio signal collected during cruise, InSight EDL, and the MarCO radio occultation are presented. Although the noise level of the MarCO radio occultation was too high for precise remote sensing of the atmosphere, the noise patterns are presented and analyzed against simulations. We compared observations with the spacecraft dynamics, Earth atmospheric and ionospheric calibrations, Martian atmospheric and ionospheric model simulations to evaluate the performance of the MarCO radio occultation. This investigation will improve our understanding of engineering and science constraints for future interplanetary cubesats.

CubeSats are small spacecraft based on a 10cm by 10cm by 10cm (1U) cube standard that have historically only been operated in Earth orbit. Mars Cube One (MarCO) is the first CubeSat mission developed for interplanetary operation. MarCO is a technology demonstration mission comprised of two identical, solar powered 6U satellites with several key goals, including that of providing a bent pipe telecom relay to Earth for NASA's InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission during its Entry, Descent, and Landing sequence. MarCO launched on the same rocket as InSight and makes use of the Deep Space Network for communications and ranging. It therefore has an attitude control system and propulsion system suitable for operating in several pointing modes, providing desaturations for reaction wheel momentum buildup, and thrusting to change the spacecraft trajectory. Because the spacecraft design is constrained to the CubeSat standards and because of the distances of the spacecraft from Earth and the Sun, the components used for attitude control and propulsion must meet tight size, mass, and power requirements. Autonomous modes of operation are also critical to ensure that the spacecraft can function safely with periods of several hours occurring between consecutive communication periods. A robust testing sequence was required to ensure that the spacecraft functions were exercised and that the operations team understood how the spacecraft were expected to behave after launch. This paper discusses several elements of the MarCO attitude control and propulsion systems. The paper begins with a discussion of the hardware that was selected for the two systems as well as descriptions of the interface between the attitude control and propulsion systems and the interface between these systems and the rest of the spacecraft's command and data handling system. Next, the paper summarizes the different types of tests that were performed at the system and spacecraft levels. Test data is included for some of these tests which helped define the methods by which the spacecraft is operated in space. Lastly, the paper lists a series of lessons-learned for developing attitude control and propulsion systems for interplanetary CubeSats.

The MarCO (Mars Cube One) spacecraft launched with the InSight mission from Vandenburg Airforce Base on May 5, 2018. These spacecraft, the first interplanetary CubeSats, serve as technology demonstrators, supporting the InSight Mars lander. During InSight’s entry, descent, and landing sequence, the MarCO spacecraft will flyby Mars, collecting transmitted data from the lander, and relaying it back to the Deep Space Network (DSN) on Earth. This serves as a demonstrator for the “carry-your-own-relay” concept that might be utilized on more challenging future missions Prior to InSight support, the mission will also demonstrate the capability for a CubeSat sized, DSN compatible deep space transponder, to independently navigate from the Earth to Mars with a small spacecraft, and flight testing for numerous commercial products. In this paper, we present a status update of the mission, an overview of early operations, and an outline for the remainder of the mission to Mars. A broad description of the planetary protection approach that MarCO utilized is provided, as well as detail of the first trajectory correction maneuver.

MARS NANO ORBITER: A CUBESAT FOR MARS SYSTEM SCIENCE. B.L. Ehlmann1,2, A. Klesh2, T. Alsedairy3, R. Dekany4, J. Dickson1, C. Edwards5, F. Forget6, A. Fraeman2, D. McCleese7, S. Murchie8, T. Usui9, S. Sugita10, K Yoshioka10, J.Baker2 1Div. of Geological & Planetary Sciences, California Institute of Technology, 2Jet Propulsion Laboratory, California Institute of Technology, 3King Abulaziz City for Science and Technology, 4Caltech Optical Observatories, Div. of Physics, Mathematics, and Astronomy, California Institute of Technology, 5Northern Arizona University, 6Laboratoire de Météorologie Dynamique, 7Synoptic Science, 8Johns Hopkins Applied Physics Laboratory 9Earth & Life Science Institute, Tokyo Institute of Technology, 10Univeristy of Tokyo

Covers advancements in spacecraft and tactical and strategic missile systems, including subsystem design and application, mission design and analysis, materials and structures, developments in space sciences, space processing and manufacturing, space operations, and applications of space technologies to other fields.

Exploration of asteroids, comets and small moons (small bodies) can answer fundamental questions relating to the formation of the solar system, the availability of resources, and the nature of impact hazards. Near-earth asteroids and the small moons of Mars are potential targets of human exploration. But as illustrated by recent missions, small body surface exploration remains challenging, expensive, and fraught with risk. Despite their small size, they are among the most extreme planetary environments, with low and irregular gravity, loosely bound regolith, extreme temperature variation, and the presence of electrically charged dust. Here we describe the Asteroid Origins Satellite (AOSAT-I), an on-orbit, 3U CubeSat centrifuge using a sandwich-sized bed of crushed meteorite fragments to replicate asteroid surface conditions. Demonstration of this CubeSat will provide a low-cost pathway to physical asteroid model validation, shed light on the origin and geophysics of asteroids, and constrain the design of future landers, rovers, resource extractors, and human missions. AOSAT-I will conduct scientific experiments within its payload chamber while operating in two distinct modes: (1) as a nonrotating microgravity laboratory to investigate primary accretion, and (2) as a rotating centrifuge producing artificial milligravity to simulate surface conditions on asteroids, comets and small moons. AOSAT-I takes advantage of low-cost, off-the-shelf components, modular design, and the rapid assembly and instrumentation of the CubeSat standard, to answer fundamental questions in planetary science and reduce cost and risk of future exploration.