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Sampling soil or rocks from extraterrestrial celestial bodies is the essential step to detecting the existence of water and life in celestial bodies, it is also an important channel to obtain scientific information about the evolution of the solar system and the origin of the universe. To date, a large number of sampling devices have been designed and developed for sampling exploration of extraterrestrial celestial bodies. However, the sampling devices are versatile, and the employed working principle and sampling methods vary in different exploration missions and celestial bodies’ environments. The present work focuses on the exploration history, celestial bodies’ environment, and sampling devices of extraterrestrial celestial bodies (mainly the Moon, Mars, and small celestial bodies), and provides a systematic review. First, the exploration history and future exploration plans of extraterrestrial celestial bodies are reviewed, which outlines the features of the exploration methods and sampling devices. In the overview of the exploration history, it is found that the failure of sampling exploration is mainly due to the unknown of the celestial bodies’ environment. Therefore, the surface environment and geology of extraterrestrial celestial bodies are further summarized, and whereby the influence of the environment on sampling device design and performance in the exploration process is analyzed. Then a focused analysis of the sampling devices that have been used in previous exploration missions and recent advances has been conducted, which provides a comprehensive description of their exploration goals, operating principles, and properties. This work summarizes the current sampling methods into nine types: excavating, drilling, grinding, grabbing, projecting, penetrating, wire-line coring, ultrasonic-assisted coring, and pneumatic, for which their advantages, disadvantages, and scope of application are analyzed. Finally, the limitations and challenges faced by extraterrestrial bodies’ sampling exploration are discussed, with prospects for future sampling exploration techniques, which can provide a reference for the subsequent in-depth development of extraterrestrial celestial bodies’ sampling devices.

The order and chaos of the motion near equilibrium points in the potential of a rotating highly irregular-shaped celestial body are investigated from point of view of the dynamical system theory. The positions of the non-degenerate equilibrium points vary continuously when the parameter changes. The topological structures in the vicinity of equilibrium points are classified into several different cases. Bifurcations at equilibrium points and the topological transfers between different cases for equilibrium points are also discussed. The conclusions can be applied to all kinds of rotating celestial bodies, simple-shaped or highly irregular-shaped, including asteroids, comets, planets, and satellites of planets to help one to understand the dynamical behaviors around them. Applications to asteroids 216 Kleopatra, 2063 Bacchus, and 25143 Itokawa are significant and interesting: Eigenvalues affiliated to the equilibrium points for the asteroid 216 Kleopatra move and always belong to the same topological cases, while eigenvalues affiliated to two different equilibrium points for the asteroid 2063 Bacchus and 25143 Itokawa move through the resonant cases of equilibrium points, and the collision of eigenvalues in the complex plane occurs. Poincaré sections in the potential of the asteroid 216 Kleopatra show the chaos behaviors of the orbits in large scale.

What follows is an exploration of medieval European astronomy focussing on the twelfth and thirteenth centuries as a period of significant change in terms of technologies and learning largely via the inheritance from Greek and Islamicate astronomical thought through translation into Latin. Robert Grosseteste (c. 1170-1253) is used as a particular focal point for discussion, setting his treatise on astronomy On the Sphere in the context of his writing on related topics and those of his contemporaries. Why contemporaries should claim astronomy as the highest of the liberal arts is understood and appreciated through the use of case study and more general reflection - and so too the limits of the discipline.

Fast radio bursts (FRBs) are brief radio emissions from distant astronomical sources. Some are known to repeat, but most are single bursts. Nonrepeating FRB observations have had insufficient positional accuracy to localize them to an individual host galaxy. We report the interferometric localization of the single-pulse FRB 180924 to a position 4 kiloparsecs from the center of a luminous galaxy at redshift 0.3214. The burst has not been observed to repeat. The properties of the burst and its host are markedly different from those of the only other accurately localized FRB source. The integrated electron column density along the line of sight closely matches models of the intergalactic medium, indicating that some FRBs are clean probes of the baryonic component of the cosmic web.

In this paper, we develop a methodology to study the periodic dynamics of irregular heterogeneous celestial bodies. Heterogeneous bodies are not scarce in space. It has been found that bodies, such as 4 Vesta, 624 Hektor, 87 Sylvia, 16 Psyche and 25143 Itokawa, may all have varied internal structures. They can be divided into large-scale and small-scale cases. The varied internal structures of large-scale bodies always result from gradient pressure inside, which leads to compactness differences of the inner material. However, the heterogeneity of a small-scale body is always reflected by the different densities of different areas, which may originate from collision formation from multiple objects. We propose a modeling procedure for the heterogeneous bodies derived from the conventional polyhedral method and then compare its dynamical characteristics with those of the homogeneous case. It is found that zero-velocity curves, positions of equilibrium points, types of bifurcations in the continuation of the orbital family and the stabilities of periodic orbits near the heterogeneous body are different from those in the homogeneous case. The suborbicular orbits near the equatorial plane are potential parking orbits for a future mission, so we discuss the switching of the orbital stability of the family because it has fundamental significance to orbit maintenance and operations around actual asteroids.

On 17 August 2017, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer detected gravitational waves (GWs) emanating from a binary neutron star merger, GW170817. Nearly simultaneously, the Fermi and INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory) telescopes detected a gamma-ray transient, GRB 170817A. At 10.9 hours after the GW trigger, we discovered a transient and fading optical source, Swope Supernova Survey 2017a (SSS17a), coincident with GW170817. SSS17a is located in NGC 4993, an S0 galaxy at a distance of 40 megaparsecs. The precise location of GW170817 provides an opportunity to probe the nature of these cataclysmic events by combining electromagnetic and GW observations.

The UK is a nation with burgeoning ambitions for its space sector, which sits alongside a strong astronomical community embedded in major international science projects on the ground and in space. As the primary representative body for UK astronomers, the Royal Astronomical Society (RAS) has the challenge of navigating these sometimes competing priorities, working to persuade the British government to give the science of astronomy the protection it requires. This paper summarises where we are, recent policy developments, and thoughts on our future plans.

Aromatic molecules such as polycyclic aromatic hydrocarbons (PAHs) are known to exist in the interstellar medium owing to their characteristic infrared emission features. However, the infrared emission only indicates the general class of molecule, and identifying which specific molecular species are present is difficult. McGuire et al. used radio astronomy to detect rotational transitions of benzonitrile emitted from a well-known nearby cloud of interstellar gas (see the Perspective by Joblin and Cernicharo). This molecule may be a precursor to more complex PAHs. The identification of benzonitrile sheds light on the composition of aromatic material within the interstellar medium—material that will eventually be incorporated into new stars and planets. Science , this issue p. 202 ; see also p. 156 Radio astronomy is used to identify the aromatic molecule benzonitrile in the interstellar medium. Polycyclic aromatic hydrocarbons and polycyclic aromatic nitrogen heterocycles are thought to be widespread throughout the universe, because these classes of molecules are probably responsible for the unidentified infrared bands, a set of emission features seen in numerous Galactic and extragalactic sources. Despite their expected ubiquity, astronomical identification of specific aromatic molecules has proven elusive. We present the discovery of benzonitrile ( c -C 6 H 5 CN), one of the simplest nitrogen-bearing aromatic molecules, in the interstellar medium. We observed hyperfine-resolved transitions of benzonitrile in emission from the molecular cloud TMC-1. Simple aromatic molecules such as benzonitrile may be precursors for polycyclic aromatic hydrocarbon formation, providing a chemical link to the carriers of the unidentified infrared bands.

Astronomical calculations reveal the Solar System’s dynamical evolution, including its chaoticity, and represent the backbone of cyclostratigraphy and astrochronology. An absolute, fully calibrated astronomical time scale has hitherto been hampered beyond ~50 million years before the present (Ma) because orbital calculations disagree before that age. Here, we present geologic data and a new astronomical solution (ZB18a) showing exceptional agreement from ~58 to 53 Ma. We provide a new absolute astrochronology up to 58 Ma and a new Paleocene–Eocene boundary age (56.01 ± 0.05 Ma). We show that the Paleocene–Eocene Thermal Maximum (PETM) onset occurred near a 405-thousand-year (kyr) eccentricity maximum, suggesting an orbital trigger. We also provide an independent PETM duration (170 ± 30 kyr) from onset to recovery inflection. Our astronomical solution requires a chaotic resonance transition at ~50 Ma in the Solar System’s fundamental frequencies.