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14 pages, 6785 KB

Open AccessArticle

Exoland Simulator, a Laboratory Device for Reflectance Spectral Analyses of Planetary Soil Analogs: Design and Simulation

by Marco Dionigi, Silvia Logozzo, Maria Cristina Valigi, Paola Comodi, Alessandro Pisello, Diego Perugini and Maximiliano Fastelli

Appl. Sci. 2024, 14(13), 5954; https://doi.org/10.3390/app14135954 - 8 Jul 2024

Viewed by 1312

Abstract

In planetary science, visible (Vis) and near-infrared (NIR) reflectance spectra allow deciphering the chemical/mineralogical composition of celestial bodies’ surfaces by comparison between remotely acquired data and laboratory references. This paper presents the design of an automated test rig named Exoland Simulator equipped with two reflectance spectrometers covering the 0.38–2.2 µm range. It is designed to collect data of natural/synthetic rocks and minerals prepared in the laboratory that simulate the composition of planetary surfaces. The structure of the test rig is conceived as a Cartesian robot to automatize the acquisition. The test rig is also tested by simulating some project trajectories, and results are presented in terms of its ability to reproduce the programmed trajectories. Furthermore, preliminary spectral data are shown to demonstrate how the soil analogs’ spectra could allow an accurate remote identification of materials, enabling the creation of libraries to study the effect of multiple chemical–physical component variations on individual spectral bands. Despite the primary scope of Exoland, it can be advantageously used also for tribological purposes, to correlate the wear behavior of soils and materials with their composition by also analyzing the wear scars. Full article

(This article belongs to the Section Surface Sciences and Technology)

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16 pages, 4389 KB

Open AccessArticle

Solar Sail Optimal Performance in Heliocentric Nodal Flyby Missions

by Giovanni Mengali, Marco Bassetto and Alessandro A. Quarta

Aerospace 2024, 11(6), 427; https://doi.org/10.3390/aerospace11060427 - 24 May 2024

Cited by 1 | Viewed by 2012

Abstract

Solar sails are propellantless propulsion systems that extract momentum from solar radiation pressure. They consist of a large ultrathin membrane, typically aluminized, that reflects incident photons from the Sun to generate thrust for space navigation. The purpose of this study is to investigate the optimal performance of a solar sail-based spacecraft in performing two-dimensional heliocentric transfers to inertial points on the ecliptic that lie within an assigned annular region centered in the Sun. Similar to ESA’s Comet Interceptor mission, this type of transfer concept could prove useful for intercepting a potential celestial body, such as a long-period comet, that is passing close to Earth’s orbit. Specifically, it is assumed that the solar sail transfer occurs entirely in the ecliptic plane and, in analogy with recent studies, the flyby points explored are between

0.85 au

and

1.35 au

from the Sun. The heliocentric dynamics of the solar sail is described using the classical two-body model, assuming the spacecraft starts from Earth orbit (assumed circular), and an ideal force model to express the sail thrust vector. Finally, no constraint is imposed on the arrival velocity at flyby. Numerical simulation results show that solar sails are an attractive option to realize these specific heliocentric transfers. Full article

(This article belongs to the Special Issue Spacecraft Orbit Transfers)

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15 pages, 264 KB

Open AccessReview

Mini-Review: Hydrogen Atoms in a High-Frequency Laser Field

by Eugene Oks

Atoms 2019, 7(3), 83; https://doi.org/10.3390/atoms7030083 - 19 Aug 2019

Viewed by 2697

Abstract

Because of the continuing advances in developing lasers in the far-ultraviolet and x-ray ranges, studies of the behavior of atoms under a high-frequency laser field are of theoretical and practical interest. In the present paper, we review various analytical results obtained by the method of separating rapid and slow subsystems for various polarizations of the laser field. Specifically, we review the corresponding analytical results both in terms of the quantum description of the phenomena involved and in terms of the classical description of the phenomena involved. We point out that, for the classical description of hydrogen atoms in a high-frequency laser field, there are interesting celestial analogies. We discuss hidden symmetries of these physical systems, the advantages of this analytical method, and the connection between these results and the transition to chaos. Full article

(This article belongs to the Special Issue Laser Plasma Spectroscopy Applications)

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