Pions and Muons from galactic cosmic ray collisions can be used to map the interior of asteroids to the meter scale and a depth of a kilometer
Established remote sensing methods provide coarse, indirect information about the interior structure of small bodies. This information is generally inferred from surface structures and overall mass density. Imagine being able to directly examine the interior of a comet or asteroid. Is the asteroid a composite of different materials or is it uniform? On a comet, how do the vents extend into the nucleus? Are there distinct interior reservoirs of volatiles? Determining the macro-scale of asteroid porosity would be fundamental to characterizing their rubble pile nature and formation and necessary for the development of planetary defense strategies. Knowledge of the interior structure and heterogeneity of comets would provide the first detailed physical constraints on jetting mechanisms, regolith formation and episodic mantle loss, while revealing interior evolutionary processes ongoing in the outer solar system. We propose to develop new types of spacecraft instrumentation, data analysis, and imaging methods that enable mapping the interior of small solar system bodies (SSBs, e.g. asteroids, comet cores and near Earth objects) to unprecedented depth and detail. Our proposed method makes use of galactic cosmic ray (GCR) secondary particle shower products, such as pions and muons. Muons, in particular, can penetrate rock to depths on the order of a kilometer and enable the deep interior of SSBs to be sampled, potentially with meter-scale spatial resolution. The secondary muons produced by GCR collisions with Earth’s atmosphere provide a convenient flux of long range particles that have already found application in volcanology, archeology, and national security, for which radiographic and tomographic methods are employed. Successful Earth surface applications demonstrate that the proposed concept is viable and that the likelihood of success is high; however, the existing muon radiography and tomography methods depend on the production of muons in Earth’s thick overlying atmosphere so that implementation of transmission radiography is straight forward. Interpretation of muon fluxes measured by a spacecraft orbiting an SSB requires separating the production of these particles in the near surface from space background contributions. In this proposal, we will use modeling to determine the magnitude of these signatures and their sensitivity to the internal and near surface structure of solar system bodies. We will also evaluate concepts for imaging systems and missions that would acquire this information.
Imagine a revolutionary way to remotely control the environment surrounding one or more roving vehicles exploring remote and unexplored areas of the Solar System, such as the dark interiors of craters or the depths of caves on Mars, the Moon, or Mercury. We call our solution “TransFormers” – multifunctional platforms that can change their shape and function and can enable new classes of in-situ planetary missions at massively reduced cost. Unfolding to large areas, they can reflect solar energy, warming and illuminating targets, powering solar panels, tracking movement and acting as a telecommunications relay.
Placed on the sunny rim of a permanently-shadowed crater, or at the entrance to a cave, Transformers can be used in conjunction with rover exploration, projecting a favorable micro-environment into cold and dark areas. These challenging sites are particularly exciting and scientifically interesting. For example, water found in the permanently shadowed areas of craters on the Moon or Mercury can reveal clues about planetary formation and history, and could be used as a resource for astronauts. Cave exploration on Mars offers the possibility of finding extraterrestrial life; furthermore, caves are time capsules preserving geochemical traces and may safely shelter future human explorers.
TransFormers present an innovative and highly adaptable way of improving survivability in such extreme environments. Our concept will enable unprecedented science and exploration of sites identified as a promising future direction for investigation in the most recent Planetary Decadal Survey.
Low-Mass Planar Photonic Imaging Sensor
A revolutionary electro-optical (EO) imaging sensor would provide a low-mass, low-volume alternative to the traditional bulky optical telescope and focal plane detector array. This imaging sensor concept consists of millions of direct detection white-light interferometers densely packed onto photonic integrated circuits (PICs) to measure the amplitude and phase of the visibility function at spatial frequencies that span the full synthetic aperture. Our approach replaces the large optics and structures required by a conventional telescope with PICs based on emerging photonic technologies which are produced by standard lithographic fabrication techniques (e.g., CMOS fabrication). By integrating advanced optical interferometry and photonics technologies, this new EO imaging sensor concept enables exciting new NASA outer planet missions since it provides a large-aperture, wide-field EO imager at a fraction of the cost, mass and volume of conventional space telescopes. As part of the initial investigations, we will study several areas tailored to potential NASA missions and requirements including, development an imaging model for potential interferometer array geometries and low light environments, evaluation of PIC architectures and corresponding signal-to-noise models, and development of a technology roadmap that addresses unique NASA mission requirements such as survivability in high radiation environments.
Ten meter suborbital balloon reflector
A project to develop suborbital, 10 meter class telescopes suitable for operation from radio to THz frequencies. The telescope consists of an inflatable, half-aluminized spherical reflector deployed within a much larger carrier balloon – either zero pressure or super pressure. Besides serving as a launch vehicle, the carrier balloon provides both a stable mount and radome for the enclosed telescope. Looking up, the LBR will serve as a telescope. Looking down, the LBR can be used for remote sensing or telecommunication activities.
Dual mode cubesat propulsion
With the cost of planetary exploration rising and budgets for such missions declining newer, cheaper, i.e. low mass, systems must be developed to perform exploration. Currently, small scientific beds which perform limited tasks are being developed and launched into Low Earth Orbit (LEO) in the form of small-scale satellite units, i.e. CubeSats, utilizing solar-based power. However, if a reasonable propulsion system could be developed, these low cost CubeSat platforms could be used to perform exploration of various extra-terrestrial bodies within the solar system; such as Europa. Current standard propulsion technology does not provide the complete answer. Chemical-based systems are high mass and provide insufficient performance for deep space missions. Electric propulsion (EP) is very efficient, i.e. high Isp, but has low thrust, leading to long mission times if orbital maneuvering is required. Thermal propulsion (TP) yields high thrust, but at the expense of a high consumption rate of propellant. Therefore, pairing an EP and TP system into a dual-mode propulsion unit becomes beneficial, where the strengths of each system are used appropriately. The high thrusting capabilities of the thermal mode are ideal for quick Earth orbit escape, drastic orbital maneuvering and orbital insertion at location. The high efficiency of the electric-mode is ideal for interplanetary travel. Researchers at the Center for Space Nuclear Research (CSNR) are proposing a radioisotope-based, dual-mode, low mass propulsion system for a CubeSat payload capable of extending their exploration realm out of LEO. Such an integrated propulsion system would allow for beneficial exploration to be conducted, even within the current budget limitations.
For the proposed work a complete system design will be provided, optimized for a Europa destination with a 10 kg payload. Modeling software such as AGI STK, COMSOL, MALTO and Aspen will be used to design and optimize the various components of the overall system. The design of an experiment will also be conducted to use existing CSNR hardware to evaluate propellant performance within the thermal mode.