| 1. |
- Palos, Mario F., et al.
(författare)
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Electric Sail Mission Expeditor, ESME : Software Architecture and Initial ESTCube Lunar Cubesat E-Sail Experiment Design
- 2023
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Ingår i: Aerospace. - : MDPI AG. - 2226-4310. ; 10:8
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Tidskriftsartikel (refereegranskat)abstract
- The electric solar wind sail, or E-sail, is a novel deep space propulsion concept which has not been demonstrated in space yet. While the solar wind is the authentic operational environment of the electric sail, its fundamentals can be demonstrated in the ionosphere where the E-sail can be used as a plasma brake for deorbiting. Two missions to be launched in 2023, Foresail-1p and ESTCube-2, will attempt to demonstrate Coulomb drag propulsion (an umbrella term for the E-sail and plasma brake) in low Earth orbit. This paper presents the next step of bringing the E-sail to deep space—we provide the initial modelling and trajectory analysis of demonstrating the E-sail in solar wind. The preliminary analysis assumes a six-unit cubesat being inserted in the lunar orbit where it deploys several hundred meters of the E-sail tether and charges the tether at 10–20 kV. The spacecraft will experience acceleration due to the solar wind particles being deflected by the electrostatic sheath around the charged tether. The paper includes two new concepts: the software architecture of a new mission design tool, the Electric Sail Mission Expeditor (ESME), and the initial E-sail experiment design for the lunar orbit. Our solar-wind simulation places the Electric Sail Test Cube (ESTCube) lunar cubesat with the E-sail tether in average solar wind conditions and we estimate a force of (Formula presented.) N produced by the Coulomb drag on a 2 km tether charged to 20 kV. Our trajectory analysis takes the 15 kg cubesat from the lunar back to the Earth orbit in under three years assuming a 2 km long tether and 20 kV. The results of this paper are used to set scientific requirements for the conceptional ESTCube lunar nanospacecraft mission design to be published subsequently in the Special Issue “Advances in CubeSat Sails and Tethers”.
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| 2. |
- Slavinskis, Andris, et al.
(författare)
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Electric Sail Test Cube–Lunar Nanospacecraft, ESTCube-LuNa: Solar Wind Propulsion Demonstration Mission Concept
- 2024
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Ingår i: Aerospace. - : MDPI AG. - 2226-4310. ; 11:3
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Tidskriftsartikel (refereegranskat)abstract
- The electric solar wind sail, or E-sail, is a propellantless interplanetary propulsion system concept. By deflecting solar wind particles off their original course, it can generate a propulsive effect with nothing more than an electric charge. The high-voltage charge is applied to one or multiple centrifugally deployed hair-thin tethers, around which an electrostatic sheath is created. Electron emitters are required to compensate for the electron current gathered by the tether. The electric sail can also be utilised in low Earth orbit, or LEO, when passing through the ionosphere, where it serves as a plasma brake for deorbiting—several missions have been dedicated to LEO demonstration. In this article, we propose the ESTCube-LuNa mission concept and the preliminary cubesat design to be launched into the Moon’s orbit, where the solar wind is uninterrupted, except for the lunar wake and when the Moon is in the Earth’s magnetosphere. This article introduces E-sail demonstration experiments and the preliminary payload design, along with E-sail thrust validation and environment characterisation methods, a cis-lunar cubesat platform solution and an early concept of operations. The proposed lunar nanospacecraft concept is designed without a deep space network, typically used for lunar and deep space operations. Instead, radio telescopes are being repurposed for communications and radio frequency ranging, and celestial optical navigation is developed for on-board orbit determination.
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| 3. |
- Jones, Geraint H., et al.
(författare)
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The Comet Interceptor Mission
- 2024
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Ingår i: Space Science Reviews. - : Springer Nature. - 0038-6308 .- 1572-9672. ; 220:1
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Tidskriftsartikel (refereegranskat)abstract
- Here we describe the novel, multi-point Comet Interceptor mission. It is dedicated to the exploration of a little-processed long-period comet, possibly entering the inner Solar System for the first time, or to encounter an interstellar object originating at another star. The objectives of the mission are to address the following questions: What are the surface composition, shape, morphology, and structure of the target object? What is the composition of the gas and dust in the coma, its connection to the nucleus, and the nature of its interaction with the solar wind? The mission was proposed to the European Space Agency in 2018, and formally adopted by the agency in June 2022, for launch in 2029 together with the Ariel mission. Comet Interceptor will take advantage of the opportunity presented by ESA’s F-Class call for fast, flexible, low-cost missions to which it was proposed. The call required a launch to a halo orbit around the Sun-Earth L2 point. The mission can take advantage of this placement to wait for the discovery of a suitable comet reachable with its minimum Δ V capability of 600 ms − 1 . Comet Interceptor will be unique in encountering and studying, at a nominal closest approach distance of 1000 km, a comet that represents a near-pristine sample of material from the formation of the Solar System. It will also add a capability that no previous cometary mission has had, which is to deploy two sub-probes – B1, provided by the Japanese space agency, JAXA, and B2 – that will follow different trajectories through the coma. While the main probe passes at a nominal 1000 km distance, probes B1 and B2 will follow different chords through the coma at distances of 850 km and 400 km, respectively. The result will be unique, simultaneous, spatially resolved information of the 3-dimensional properties of the target comet and its interaction with the space environment. We present the mission’s science background leading to these objectives, as well as an overview of the scientific instruments, mission design, and schedule.
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