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The radio sky at frequencies of several MHz and below is essentially unexpected with high angular resolution due to refraction and opacity in the Earth's ionosphere.
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A discussion on the science from upcoming NASA Commercial Lunar Payload Services (CLPS) missions to the lunar surface with low frequency (<100 kHz) astronomy instruments.
A discussion on the science from upcoming NASA Commercial Lunar Payload Services (CLPS) missions to the lunar surface with low frequency (<100 kHz) astronomy instruments.
A discussion on the science from upcoming NASA Commercial Lunar Payload Services (CLPS) missions to the lunar surface with low frequency (<100 kHz) astronomy instruments.
A discussion on the science from upcoming NASA Commercial Lunar Payload Services (CLPS) missions to the lunar surface with low frequency (<100 kHz) astronomy instruments.
A discussion on the science from upcoming NASA Commercial Lunar Payload Services (CLPS) missions to the lunar surface with low frequency (<100 kHz) astronomy instruments.
Because of terrestrial ionospheric absorption, very little is known of the radio sky beyond 10 m wavelength. An extremely simple, low cost very low frequency radio telescope is proposed, consisting of a large array of short wires laid on the lunar surface, each wire equipped with an amplifier and a digitizer, and connected to a common computer. The telescope could do simultaneous multifrequency observations of much of the visible sky with high resolution in the 10 to 100 m wavelength range, and with lower resolution in the 100 to 1000 m range. It would explore structure and spectra of galactic and extragalactic point sources, objects, and clouds, and would produce detailed quasi-three-dimensional mapping of interstellar matter within several thousand parsecs of the Sun.
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Radioastronomical observations of moon and planets
Experiments on earth and moon dealing with radio, optical, X-ray and gamma ray astronomy based on Lunar Exploration System for Apollo /LESA/ REPORT
The Lunar Surface Electromagnetics Explorer - Night, LuSEE-Night, is a low-frequency radio astronomy experiment that will explore the cosmic Dark Ages signal on the radio quiet farside of the Moon. The LuSEE-Night carries a radio frequency spectrometer consisting of a set of antennas, analog and digital processing electronics, and will be launched by NASA's Commercial Lunar Payload Services in 2025. The spectrometer is designed to observe the spectrum of the radio sky in the 0.5−50MHz band. The engineering model (EM) of the four-channel spectrometer has been developed. The EM has been characterized for linearity, gain, noise, and their temperature dependence, confirming that the EM meets all the requirements for LuSEE-Night. Three mitigation techniques have been implemented and verified to suppress self-induced electromagnetic interference (EMI). The flight model of the spectrometer is currently being developed and is scheduled to be shipped to the integration site in early 2024
No abstract provided
Cis-lunar space offers affordable near-term opportunities to help pave the way for future global human exploration of deep space, acting as a bridge between present missions and future deep space missions. While missions in cis-lunar space have value unto themselves, they can also play an important role in enabling and reducing risk for future human missions to the Moon, Near-Earth Asteroids (NEAs), Mars, and other deep space destinations. The Cis-Lunar Destination Team of NASA's Human Spaceflight Architecture Team (HAT) has been analyzing cis-lunar destination activities and developing notional missions (or "destination Design Reference Missions" [DRMs]) for cis-lunar locations to inform roadmap and architecture development, transportation and destination elements definition, operations, and strategic knowledge gaps. The cis-lunar domain is defined as that area of deep space under the gravitational influence of the earth-moon system. This includes a set of earth-centered orbital locations in low earth orbit (LEO), geosynchronous earth orbit (GEO), highly elliptical and high earth orbits (HEO), earth-moon libration or "Lagrange" points (E-ML1 through E-ML5, and in particular, E-ML1 and E-ML2), and low lunar orbit (LLO). To help explore this large possibility space, we developed a set of high level cis-lunar mission concepts in the form of a large mission tree, defined primarily by mission duration, pre-deployment, type of mission, and location. The mission tree has provided an overall analytical context and has helped in developing more detailed design reference missions that are then intended to inform capabilities, operations, and architectures. With the mission tree as context, we will describe two destination DRMs to LEO and GEO, based on present human space exploration architectural considerations, as well as our recent work on defining mission activities that could be conducted with an EML1 or EML2 facility, the latter of which will be an emphasis of this paper, motivated in part by recent interest expressed at the Global Exploration Roadmap Stakeholder meeting. This paper will also explore the links between this HAT Cis-Lunar Destination Team analysis and the recently released ISECG Global Exploration Roadmap and other potential international considerations, such as preventing harmful interference to radio astronomy observations in the shielded zone of the moon.
The sources and sinks of the present trace lunar atmosphere can be accounted for. In particular, it is clear that the solar wind is the primary agent for rapidly removing gases, other than H2 which can escape thermally. But the solar wind has only a finite capability for stripping. If gases are added at rates approaching 100 g/sec, an atmosphere will begin to accumulate. Transition to a state where thermal escape dominates, solar wind loss occurs when the atmosphere has accumulated a total mass of about 108 kg. Assuming that disturbing the lunar regolith liberates about 10-4 by mass of trapped gases, this implies that some kinds of mining operation could handle up to 109 tons of material before creating a long lived, albeit still exceedingly tenuous, atmosphere which would have no appreciable influence on most lunar activities. Should the lunar atmosphere ever exceed an abundance matching that of the Earth at 120 km altitude, ever larger UV wavelengths ranges would be inhibited or lost, as would probably be the ability to use the Moon as a base for very low frequency radio astronomy.
The best location in the inner solar system for the grand observatories of the 21st century may be the moon. A multidisciplinary team including university students and faculty in engineering, astronomy, physics, and geology, and engineers from industry is investigating the moon as a site for astronomical observatories and is doing conceptual and preliminary designs for these future observatories. Studies encompass lunar facilities for radio astronomy and astronomy at optical, ultraviolet, and infrared wavelengths of the electromagnetic spectrum. Although there are significant engineering challenges in design and construction on the moon, the rewards for astronomy can be great, such as detection and study of earth-like planets orbiting nearby stars, and the task for engineers promises to stimulate advances in analysis and design, materials and structures, automation and robotics, foundations, and controls. Fabricating structures in the reduced-gravity environment of the moon will be easier than in the zero-gravity environment of earth orbit, as Apollo and space-shuttle missions have revealed. Construction of observatories on the moon can be adapted from techniques developed on the earth, with the advantage that the moon's weaker gravitational pull makes it possible to build larger devices than are practical on earth.
It is presently noted that the moon furnishes a stable and radio-quiet platform for astronomy and space physics, as well as a source for such materials resources as Si, Al, Fe, O, Mg, and Ti, and a base for low cost interplanetary exploration. Attention is given to a vehicle designated the 'Lunar Geochemical Orbiter', and it is recommended that the prospective NASA Space Station's structural modules be designed for lunar as well as orbital use. Further, design studies should be initiated for a manned orbital transfer vehicle (whose propulsion system may be nuclear).
A dynamic constellation of microspacecraft in lunar orbit can carry out valuable radio astronomy investigations in the frequency range of 30kHz--30MHz, a range that is difficult to explore from Earth. In contrast to the radio astronomy ivestigations that have flown on individual spacecraft, the four microspacecraft together with a carrier spacecraft, which transported them to lunar orbit, form an interferometer with far superior angular resolution. Use of microspacecraft allows the entire constellation to be launched with a Taurus-class vehicle. Also distinguishing this approach is that the Moon is used as needed to shield the constellation from RF interference from the Earth and Sun.