We report about observations of the solar U+III bursts on 5 June of 2020 by means of a new active antenna designed to receive radiation in 4-70 MHz. This instrument can serve as a prototype of the ultra-long-wavelength radiotelescope for observations on the farside of the Moon. Our analysis of experimental data is based on simultaneous records obtained with the antenna arrays GURT and NDA in high frequency and time resolution, e-Callisto network as well as by using the space-based observatories STEREO and WIND. The results from this observational study confirm the model of Reid and Kontar (2017).
Electrical coupling of a horizontal dipole antenna to a dielectric half-space: applications to radio astronomy from the lunar surface
Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；University of California, Berkeley（加州大学伯克利分校）；The Blackett Laboratory, Imperial College London（帝国理工学院布莱克特实验室）；Brookhaven National Laboratory（布鲁克海文国家实验室）
The Lunar Gravitational--Wave Antenna is a proposed low-frequency gravitational-wave detector on the Moon surface. It will be composed of an array of high-end cryogenic superconducting inertial sensors (CSISs). A cryogenic environment will be used in combination with superconducting materials to open up pathways to low-loss actuators and sensor mechanics. CSIS revolutionizes the (cryogenic) inertial sensor field with a modelled displacement sensitivity at 0.5 Hz of 3 orders of magnitude better than the current state-of-the-art. It will allow the Lunar Gravitational-Wave Antenna to be sensitive…
The active broadband (1 kHz-100 MHz) tripole antenna now envisaged to be placed on the European Lunar Lander located at the Lunar South Pole allows for sensitive measurements of the exosphere and ionosphere, and their interaction with the Earths magnetosphere, solar particles, wind and CMEs and studies of radio communication on the moon, that are essential for future lunar human and science exploration. In addition, the lunar South pole provides an excellent opportunity for radio astronomy. Placing a single radio antenna in an eternally dark crater or behind a mountain at the south (or north) …
Site selection for the Laser Interferometer Lunar Antenna (LILA)
Vanderbilt University（范德堡大学）；Lunar Resources, Inc.（月球资源有限公司）；University of Texas Rio Grande Valley（得克萨斯大学里奥格兰德河谷分校）；Université Paris Cité, Institut de physique du globe de Paris, CNRS（巴黎西岱大学，巴黎地球物理研究所，法国国家科学研究中心）；California Institute of Technology（加州理工学院）；Johns Hopkins Applied Physics Laboratory（约翰斯·霍普金斯大学应用物理实验室）
Earth-based observations are complicated by the opacity of Earth's ionosphere at very low frequencies and strong man-made radio frequency interference. This explains long standing interest in building a low frequency radio telescope on the farside of the Moon. Experience from ground-based observations near the ionospheric cutoff in dealing with the interference, ionosphere, and wide-field imaging/dynamic range problems provides crucial information for future radioastronomic experiments on the Moon. In this purpose we observed non-intensive solar bursts on the example of solar drift pairs (DP) …
Seismic background mitigation with the Lunar Gravitational-wave Antenna
Peking University（北京大学）；Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学卡尔弗天体物理研究所）；Gran Sasso Science Institute（格兰萨索科学研究所）；INFN, Laboratori Nazionali del Gran Sasso（意大利国家核物理研究所，格兰萨索国家实验室）
The detections of small, rocky exoplanets have surged in recent years and will likely continue to do so. To know whether a rocky exoplanet is habitable, we have to characterise its atmosphere and surface. A promising characterisation method for rocky exoplanets is direct detection using spectropolarimetry. This method will be based on single pixel signals, because spatially resolving exoplanets is impossible with current and near-future instruments. Well-tested retrieval algorithms are essential to interpret these single pixel signals in terms of atmospheric composition, cloud and surface cove…
Observing Double White Dwarfs with the Lunar GW Antenna
Università di Padova（帕多瓦大学）；Gran Sasso Science Institute (GSSI)（格兰萨索科学研究所）；INFN, Laboratori Nazionali del Gran Sasso（意大利国家核物理研究所，格兰萨索国家实验室）；INFN, Sezione di Padova（意大利国家核物理研究所，帕多瓦分部）
The August 2009 edition of the AAO newsletter contains articles on observations of the lunar impact of the Kaguya satellite, mapping the ISM towards Omega Centauri, early results from the Anglo-Australian Rocky Planet search, details of a new AAOmega observing mode, the new telescope control system and a number of regular features.
Monitoring of vibrational eigenmodes of an elastic body excited by gravitational waves was one of the first concepts proposed for the detection of gravitational waves. At laboratory scale, these experiments became known as resonant-bar detectors first developed by Joseph Weber in the 1960s. Due to the dimensions of these bars, the targeted signal frequencies were in the kHz range. Weber also pointed out that monitoring of vibrations of Earth or Moon could reveal gravitational waves in the mHz band. His Lunar Surface Gravimeter experiment deployed on the Moon by the Apollo 17 crew had a technic…
The Radio-wave Observations at the Lunar Surface of the photoElectron Sheath (ROLSES) instrument onboard the Intuitive Machines-1 Mission to the Moon
NASA/GSFC（美国国家航空航天局戈达德太空飞行中心）；Space Science Institute（空间科学研究所）；DeepSpace Technologies（深空技术公司）；University of Colorado, Boulder（科罗拉多大学博尔德分校）；University of California, Berkeley（加州大学伯克利分校）
Results from NASA's First Radio Telescope on the Moon: Terrestrial Technosignatures and the Low-Frequency Galactic Background Observed by ROLSES-1 Onboard the Odysseus Lander
The farside of the Moon is a pristine, quiet platform to conduct low radio frequency observations of the early Universe's Dark Ages, as well as space weather and magnetospheres associated with habitable exoplanets. In this paper, the astrophysics associated with NASA-funded concept studies will be described including a lunar-orbiting spacecraft, DAPPER, that will measure the 21 cm global spectrum at redshifts 40-80, and an array of low frequency dipoles on the lunar farside surface, FARSIDE, that would detect exoplanet magnetic fields. DAPPER observations (17-38 MHz), using a single cross-dipo…
The Simons Observatory (SO) is a ground-based cosmic microwave background survey experiment that consists of three 0.5 m small-aperture telescopes and one 6 m large-aperture telescope, sited at an elevation of 5200 m in the Atacama Desert in Chile. SO will study the polarization and temperature anisotropies of the Cosmic Microwave Background (CMB). The observatory will require well-understood telescope pointing and scanning. Good antenna control will allow us to execute the scan strategy devised to optimize sensitivity to our scientific goals, calibrate the system with celestial targets, and m…
Quantifying Foreground Contamination in the Dark Ages 21 cm Power Spectrum Using an Electromagnetically Simulated Dipole Antenna Atop a Dielectric Surface
Brown University（布朗大学）；National Radio Astronomy Observatory（国家射电天文台）；University of Colorado Boulder（科罗拉多大学博尔德分校）；Lunar Resources, Inc.（月球资源公司）
An array of low-frequency dipole antennas on the lunar farside surface will probe a unique, unexplored epoch in the early Universe called the Dark Ages. It begins at Recombination when neutral hydrogen atoms formed, first revealed by the cosmic microwave background. This epoch is free of stars and astrophysics, so it is ideal to investigate high energy particle processes including dark matter, early Dark Energy, neutrinos, and cosmic strings. A NASA-funded study investigated the design of the instrument and the deployment strategy from a lander of 128 pairs of antenna dipoles across a 10 kmx10…
First Lunar Farside SETI Observations for Periodic Signals with the Low-frequency Radio Spectrometer of Chang'E-4 Mission
Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University（北京师范大学天文与前沿科学研究院）；School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院）；Institute for Astronomical Science, Dezhou University（德州大学天理研究所）；College of Computer and Information, Dezhou University（德州大学计算机与信息学院）；Institute for Astrophysics, Zhengzhou University（郑州大学天体物理研究所）
FARSIDE (Farside Array for Radio Science Investigations of the Dark ages and Exoplanets) is a Probe-class concept to place a low radio frequency interferometric array on the farside of the Moon. A NASA-funded design study, focused on the instrument, a deployment rover, the lander and base station, delivered an architecture broadly consistent with the requirements for a Probe mission. This notional architecture consists of 128 dual polarization antennas deployed across a 10 km area by a rover, and tethered to a base station for central processing, power and data transmission to the Lunar Gatewa…
Particle cascades induced by ultra-high-energy (UHE) cosmic rays and neutrinos impacting on the lunar regolith usually radiate Cherenkov radio emissions due to the presence of excess negative charge, which is known as Askaryan effect. Several experiments have been carried out to detect the Cherenkov radio emissions in the lunar regolith. To prepare for future lunar Ultra-Long Wavelength (ULW, frequencies below 30 MHz) radio astronomy missions, we study the detection of the Cherenkov radio emissions with the ULW radio telescope that are operating at the lunar orbit. We have carried out instrume…
In this paper we investigate the correlation between the atmospheric perturbations at Paranal Observatory and the Chilean coast tides, which are mostly modulated by the 14-day syzygy solar-lunar tidal cycle. To this aim, we downloaded 15 years (2003-2017) of cloud coverage data from the AQUA satellite, in a matrix that includes also Armazones, the site of the European Extremely Large Telescope. By applying the Fast Fourier Transform to these data we detected a periodicity peak of about 14 days. We studied the tide cycle at Chanaral De Las Animas, on the ocean coast, for the year 2017, and we c…
We measured the components of the 31-m-long vector between the two Very-Long-Baseline Interferometry (VLBI) antennas at the Kokee Park Geophysical Observatory (KPGO), Hawaii, with approximately 1 mm precision using phase-delay observables from dedicated VLBI observations in 2016 and 2018. The two KPGO antennas are the 20 m legacy VLBI antenna and the 12 m VLBI Global Observing System (VGOS) antenna. Independent estimates of the vector between the two antennas were obtained by the National Geodetic Survey (NGS) using standard optical surveys in 2015 and 2018. The uncertainties of the latter sur…
We describe a new space gravitational wave observatory design called LAGRANGE that maintains all important LISA science at about half the cost and with reduced technical risk. It consists of three drag-free spacecraft in the most stable geocentric formation, the Earth-Moon L3, L4, and L5 Lagrange points. Fixed antennas allow continuous contact with the Earth, solving the problem of communications bandwidth and latency. A 70 mm diameter AuPt sphere with a 35 mm gap to its enclosure serves as a single inertial reference per spacecraft, which is operated in "true" drag-free mode (no test mass for…
A new era of exploration of the low radio frequency Universe from the Moon will soon be underway with landed payload missions facilitated by NASA's Commercial Lunar Payload Services (CLPS) program. CLPS landers are scheduled to deliver two radio science experiments, ROLSES to the nearside and LuSEE to the farside, beginning in 2021. These instruments would be pathfinders for a 10-km diameter interferometric array, FARSIDE, composed of 128 pairs of dipole antennas proposed to be delivered to the lunar surface later in the decade. ROLSES and LuSEE, operating at frequencies from 100 kHz to a few …
During the past decade there have been several attempts to detect cosmogenic ultra high energy (UHE) neutrinos by searching for radio Cerenkov bursts resulting from charged impact showers in terrestrial ice or the lunar regolith. So far these radio searches have yielded no detections, but the inferred flux upper limits have started to constrain physical models for UHE neutrino generation. For searches which use the Moon as a target, we summarize the physics of the interaction, properties of the resulting Cerenkov radio pulse, detection statistics, effective aperture scaling laws, and derivatio…
The location of an astronomical observatory is a key factor that affects its scientific productivity. The best astronomical sites are generally those found at high altitudes. Several such sites in western China and the Tibetan plateau are presently under development for astronomy. One of these is Ali, which at over 5000 m is one of the highest astronomical sites in the world. In order to further investigate the astronomical potential of Ali, we have installed a lunar scintillometer, for the primary purpose of profiling atmospheric turbulence. This paper describes the instrument and technique, …
(Abridged) Lunar occultations (LO) are a very efficient and powerful technique, that achieves the best combination of high angular resolution and sensitivity possible today at near-infrared wavelengths. Given that the events are fixed in time, that the sources are occulted randomly, and that the telescope use is minimal, the technique is very well suited for service mode observations. We have established a program of routine LO observations at the VLT observatory, especially designed to take advantage of short breaks available in-between other programs. We have used the ISAAC instrument in bur…
Chang'e 7 Lunar Lander Optical Camera-Telescope: Optical Astronomy from the Moon
The University of Hong Kong（香港大学）；National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）；International Lunar Observatory Association（国际月球观测站联盟）
The European Moon Rover System: a modular multipurpose rover for future complex lunar missions
GMV Aerospace and Defence SAU（GMV航空航天与防务公司）；GMV NSL Ltd（GMV NSL有限公司）；AVS Added Value Solutions（AVS增值解决方案公司）；OHB System AG（OHB系统股份公司）；Hellenic Technology of Robotics（希腊机器人技术公司）；German Aerospace Center (DLR)（德国航空航天中心）；ESTEC, ESA（欧洲空间研究与技术中心）
The Rosse Solar-Terrestrial Observatory (RSTO; www.rosseobservatory.ie) was established at Birr Castle, Co. Offaly, Ireland (53 05'38.9", 7 55'12.7") in 2010 to study solar radio bursts and the response of the Earth's ionosphere and geomagnetic field. To date, three Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) spectrometers have been installed, with the capability of observing in the frequency range 10-870 MHz. The receivers are fed simultaneously by biconical and log-periodic antennas. Nominally, frequency spectra in the ran…
Beyond Sgr A* and M87*: Sub-Microarcsecond Black Hole Shadow Detection via Lunar-based Extremely Long Baseline Interferometry
Shanghai Astronomical Observatory, Chinese Academy of Sciences（中国科学院上海天文台）；Key Laboratory of Radio Astronomy and Technology, Chinese Academy of Sciences（中国科学院射电天文与技术重点实验室）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；Tsung-Dao Lee Institute, Shanghai Jiao Tong University（上海交通大学李政道研究所）；School of Physics and Astronomy, Shanghai Jiao Tong University（上海交通大学物理与天文学院）；Institut für Theoretische Physik, Goethe-Universität（法兰克福大学理论物理研究所）
We present the technical specifications and first results of the ESA-funded, lunar monitoring project "NELIOTA" (NEO Lunar Impacts and Optical TrAnsients) at the National Observatory of Athens, which aims to determine the size-frequency distribution of small Near-Earth Objects (NEOs) via detection of impact flashes on the surface of the Moon. For the purposes of this project a twin camera instrument was specially designed and installed at the 1.2 m Kryoneri telescope utilizing the fast-frame capabilities of scientific Complementary Metal-Oxide Semiconductor detectors (sCMOS). The system provid…
Small-Body Science with the Nautilus Space Observatory: From Cislunar Space Resilience to Mapping the Kuiper-Belt-to-Oort-Cloud Transition
Massachusetts Institute of Technology（麻省理工学院）；Space Science Institute（太空科学研究所）；Lawrence Livermore National Laboratory（劳伦斯利弗莫尔国家实验室）；Steward Observatory, The University of Arizona（亚利桑那大学斯蒂沃德天文台）；Lunar and Planetary Laboratory, University of Arizona（亚利桑那大学月球与行星实验室）；Alien Earths Team, NASA ICAR/NExSS（NASA ICAR/NExSS 外星地球团队）；Space Telescope Science Institute（空间望远镜科学研究所）
This is an account of the Millimeter Wave Observatory, a 4.9 meter diameter antenna facility that pioneered continuum observations of planets and interstellar molecular spectroscopy from 1971 to 1988. The circumstances of its founding, development of its instrumentation, and major research contributions are discussed. The MWO role in training of personnel in this new field is illustrated by a listing of student and postdoctoral observers, with titles of PhD theses that included MWO data.
A prototype for dedicated observations of pulsars and other astrophysical transients in the frequency range 50\,-\,80\,MHz has been recently commissioned at the Gauribidanur radio observatory near Bangalore in India. The antenna set-up, analog \& digital receiver systems, and the initial observations are presented.
Brookhaven National Laboratory（布鲁克海文国家实验室）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；University of California, Berkeley（加州大学伯克利分校）；University of Colorado Boulder（科罗拉多大学博尔德分校）；University of Minnesota（明尼苏达大学）；Université Paris-Cité（巴黎西岱大学）
Tunka-Rex is the radio extension of the Tunka cosmic-ray observatory in Siberia close to Lake Baikal. Since October 2012 Tunka-Rex measures the radio signal of air-showers in coincidence with the non-imaging air-Cherenkov array Tunka-133. Furthermore, this year additional antennas will go into operation triggered by the new scintillator array Tunka-Grande measuring the secondary electrons and muons of air showers. Tunka-Rex is a demonstrator for how economic an antenna array can be without losing significant performance: we have decided for simple and robust SALLA antennas, and we share the ex…
The next-generation Very Large Array (ngVLA) is an astronomical observatory planned to operate at centimeter wavelengths (25 to 0.26 centimeters, corresponding to a frequency range extending from 1.2 to 116 GHz). The observatory will be a synthesis radio telescope constituted of approximately 244 reflector antennas each of 18 meters diameter, and 19 reflector antennas each of 6 meters diameter, operating in a phased or interferometric mode. We provide a technical overview of the Reference Design of the ngVLA. This Reference Design forms a baseline for a technical readiness assessment and the c…
CODALEMA is one of the pioneer experiments dedicated to the recent field of cosmic ray radio detection. It is located at the radio observatory of Nancay (France). The detector setup combined until recently a ground particle detector and an array of active dipole antennas covering a total area of 0.25 km^2. The experiment is now going through a major upgrade with the deployment around the existing apparatus of a Standalone Antenna Array, which consists of 60 standalone new generation radio-detection stations and which will cover an area of 1.5 km^2 (33 stations deployed over the spring of 2011 …
The next-generation Very Large Array (ngVLA) is an astronomical observatory planned to operate at centimeter wavelengths (25 to 0.26 centimeters, corresponding to a frequency range extending from 1.2 GHz to 116 GHz). The observatory will be a synthesis radio telescope constituted of approximately 214 reflector antennas each of 18 meters diameter, operating in a phased or interferometric mode. We provide an overview of the current system design of the ngVLA. The concepts for major system elements such as the antenna, receiving electronics, and central signal processing are presented. We also de…
