Ioannis Gkolias

Ioannis Gkolias
Aristotle University of Thessaloniki | AUTH · Division of Physics (PHYS)

Doctor of Philosophy

About

36
Publications
5,498
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265
Citations

Publications

Publications (36)
Article
Full-text available
We consider Earth satellite orbits in the range of semi-major axes where the perturbing effects of Earth's oblateness and lunisolar gravity are of comparable order. This range covers the medium-Earth orbits (MEO) of the Global Navigation Satellite Systems and the geosynchronous orbits (GEO) of the communication satellites. We recall a secular and q...
Article
Full-text available
In this work the orbital dynamics of Earth satellites about the geosynchronous altitude are explored, with primary goal to assess current mitigation guidelines as well as to discuss the future exploitation of the region. A thorough dynamical mapping was conducted in a high-definition grid of orbital elements, enabled by a fast and accurate semi-ana...
Article
The NASA Double Asteroid Redirection Test (DART) mission is a planetary defense-driven test of a kinetic impactor on Dimorphos, the satellite of the binary asteroid 65803 Didymos. DART will intercept Dimorphos at a relative speed of ∼6.5km s−1, perturbing Dimorphos’s orbital velocity and changing the binary orbital period. We present three independ...
Article
Full-text available
The Double Asteroid Redirection Test (DART) mission will be the first test of a kinetic impactor as a means of planetary defense. In late 2022, DART will collide with Dimorphos, the secondary in the Didymos binary asteroid system. The impact will cause a momentum transfer from the spacecraft to the binary asteroid, changing the orbit period of Dimo...
Article
Full-text available
Navigation satellites are known from numerical studies to reside in a dynamically sensitive environment, which may be of profound importance for their long-term sustainability. We derive the fundamental Hamiltonian of Global Navigation Satellite System dynamics and show analytically that near-circular trajectories lie in the neighborhood of a Norma...
Preprint
Full-text available
NASA's Double Asteroid Redirection Test (DART) spacecraft is planned to impact the natural satellite of (65803) Didymos, Dimorphos, around 23:14 UTC on 26 September 2022, causing a reduction in its orbital period that will be measurable with ground-based observations. This test of kinetic impactor technology will provide the first estimate of the m...
Article
Full-text available
Despite extended past studies, several questions regarding the resonant structure of the medium-Earth orbit (MEO) region remain hitherto unanswered. This work describes in depth the effects of the 2g+h\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{ma...
Preprint
Full-text available
The Double Asteroid Redirection Test (DART) mission will be the first test of a kinetic impactor as a means of planetary defense. In late 2022, DART will collide with Dimorphos, the secondary in the Didymos binary asteroid system. The impact will cause a momentum transfer from the spacecraft to the binary asteroid, changing the orbit period of Dimo...
Preprint
Full-text available
Despite extended past studies, several questions regarding the resonant structure of the medium-Earth orbit (MEO) region remain hitherto unanswered. This work describes in depth the effects of the $2g+h$ lunisolar resonance. In particular, (i) we compute the correct forms of the separatrices of the resonance in the inclination-eccentricity space fo...
Preprint
Full-text available
The NASA Double Asteroid Redirection Test (DART) mission is a planetary defense-driven test of a kinetic impactor on Dimorphos, the satellite of the binary asteroid 65803 Didymos. DART will intercept Dimorphos at a relative speed of ${\sim}6.5 \text{ km s}^{-1}$, perturbing Dimorphos's orbital velocity and changing the binary orbital period. We pre...
Presentation
Full-text available
Highlights: - Exploiting the effects of lunisolar perturbation and the J2 effect to dispose of GEO satellites via re-entry through a mechanism of long-term eccentricity build-up. - Interfacing the long-term averaged propagation with the destructive re-entry analysis using the concept of overshoot boundary. - Statistical analysis of the condition...
Article
Full-text available
Recent works demonstrated that the dynamics caused by the planetary oblateness coupled with the solar radiation pressure can be described through a model based on singly averaged equations of motion. The coupled perturbations affect the evolution of the eccentricity, inclination and orientation of the orbit with respect to the Sun–Earth line. Reson...
Preprint
Recent works demonstrated that the dynamics caused by the planetary oblateness coupled with the solar radiation pressure can be described through a model based on singly-averaged equations of motion. The coupled perturbations affect the evolution of the eccentricity, inclination and orientation of the orbit with respect to the Sun--Earth line. Reso...
Article
Full-text available
Space debris represents a threat to space missions and operational satellites. Failing to control its growth might lead to the inability to use near-Earth space. However, this issue is still largely unknown to most people. In this paper, we present an educational experience in virtual reality created to raise awareness about the problem of space de...
Conference Paper
The ReDSHIFT (Revolutionary Design of Spacecraft through Holistic Integration of Future Technologies) project focused during three years on various means to reduce the impact of space debris. The project investigated the synergy between theoretical and experimental results (long-term simulations, astrodynamics, passive de-orbiting devices, 3D print...
Conference Paper
Recent works demonstrated that the dynamics caused by the planetary oblateness coupled with the solar radiation pressure can be described by means of an analytical model based on singly-averaged equations of motion. The coupled perturbations affect the evolution of the eccentricity, inclination and orientation of the orbit with respect to the Sun-E...
Conference Paper
Full-text available
Among its results, the ReDSHIFT project has developed a software tool for spacecraft operators, space agencies and research institutions to design the end-of-life of Earth-based missions and to study the interaction with the space debris environment. As part of this, the “Disposal Mapping” module, presented in this paper in its structure and algori...
Conference Paper
Full-text available
The ReDSHIFT (Revolutionary Design of Spacecraft through Holistic Integration of Future Technologies) project was concluded on March 31, 2019. The 3-year project involved 13 European partners and was aimed at studying, implementing and testing novel solutions for space debris mitigation. The focus was on passive means to reduce the impact of Space...
Preprint
Full-text available
Navigation satellites are known from numerical studies to reside in a dynamically sensitive environment, which may be of profound importance for their long-term sustainability. We derive the fundamental Hamiltonian of GNSS dynamics and show analytically that near-circular trajectories lie in the neighborhood of a Normally Hyperbolic Invariant Manif...
Conference Paper
Small constellations of satellites in Inclined Geosynchronous Orbits (IGSO) provide an alternative to the increasingly crowded Geostationary Equatorial Orbit (GEO) belt. Satellite platforms equipped with electric propulsion systems increase in popularity since they broaden the mission design opportunities due to the potentially significant propella...
Conference Paper
This paper investigates low-thrust station-keeping strategies for geostationary satellites. On the contratry to traditional low-thrust control methods, which requires ground-station operations in a daily basis, the proposed method maximises the exploitation of natural dynamics and allows for the design of an efficient control within a predefined sl...
Preprint
Full-text available
Accepted for publications in Communications in Nonlinear Science and Numerical Simulation, 2019
Article
We provide an analytical approximation to the dynamics in each of the three most important low order secondary resonances (1:1, 2:1, and 3:1) bifurcating from the synchronous primary resonance in the gravitational spin-orbit problem. To this end we extend the perturbative approach introduced in [10], based on normal form series computations. This a...
Preprint
Full-text available
In this work the orbital dynamics of Earth satellites about the geosynchronous altitude are explored, with primary goal to assess current mitigation guidelines as well as to discuss the future exploitation of the region. A thorough dynamical mapping was conducted in a high-definition grid of orbital elements, enabled by a fast and accurate semi-ana...
Conference Paper
Full-text available
This work presents the design of optimal strategies for the post-mission disposal of satellites in high-altitude orbits by exploiting the luni-solar effects. The dynamic of distant Earth satellites is mainly influenced by the third body perturbations of the Moon and the Sun, coupled with the Earth’s oblateness. In this paper, an analytical model is...
Conference Paper
Full-text available
In this work, we exploit the luni-solar perturbations for the post-mission disposal of satellites in high-altitude orbits. Starting from the double-averaged dynamical system, the representation of the dynamics is reduced to a one degree-of-freedom Hamiltonian, depending on the orbit eccentricity and the perigee orientation in the equatorial frame....
Conference Paper
One of the deliverables of the ReDSHIFT H2020 project will be a software tool available to the scientific community and the wider public. The ReDSHIFT software is thought as a tool for spacecraft operators, space agencies and research institutions to design the end-of-life of any Earth satellite mission and to study the interaction with the space d...
Conference Paper
The ReDSHIFT (Revolutionary Design of Spacecraft through Holistic Integration of Future Technologies) project has been approved by the European Community in the framework of the H2020 Protec 2015 call, focused on passive means to reduce the impact of Space Debris by prevention, mitigation and protection. The main innovative aspects of the project c...
Article
Full-text available
The H2020 ReDSHIFT project aims at finding passive means to mitigate the proliferation of space debris. This goal is pursued by a twofold research activity based on theoretical astrodynamics, computer simulations and the analysis of legal aspects of space debris, coupled with an experimental activity on advanced additive manufacturing (3D printing)...
Article
Full-text available
The slow deformation of terrestrial orbits in the medium range, subject to lunisolar resonances, is well approximated by a family of Hamiltonian flow with $2.5$ degree-of-freedom. The action variables of the system may experience chaotic variations and large drift that we may quantify. Using variational chaos indicators, we compute high-resolution...
Article
In a realistic scenario, the evolution of the rotational dynamics of a celestial or artificial body is subject to dissipative effects. Time-varying non-conservative forces can be due to, for example, a variation of the moments of inertia or to tidal interactions. In this work, we consider a simplified model describing the rotational dynamics, known...
Article
We study the resonant dynamics in a simple one degree of freedom, time dependent Hamiltonian model describing spin-orbit interactions. The equations of motion admit periodic solutions associated with resonant motions, the most important being the synchronous one in which most evolved satellites of the Solar system, including the Moon, are observed....
Article
Full-text available
Do nonlinear waves destroy Anderson localization? Computational and experimental studies yield subdiffusive nonequilibrium wave packet spreading. Chaotic dynamics and phase decoherence assumptions are used for explaining the data. We perform a quantitative analysis of the nonequilibrium chaos assumption, and compute the time dependence of main chao...
Article
Full-text available
The motion of a satellite around a planet can be studied by the Hill model, which is a modification of the restricted three body problem pertaining to motion of a satellite around a planet. Although the dynamics of the circular Hill model have been extensively studied in the literature, only few results about the dynamics of the elliptic model were...

Projects

Projects (3)
Project
Space benefits mankind through the services it provides to Earth. Future space activities progress thanks to space transfer and are safeguarded by space situation awareness. Natural orbit perturbations are responsible for the trajectory divergence from the nominal two-body problem, increasing the requirements for orbit control; whereas, in space situation awareness, they influence the orbit evolution of space debris that could cause hazard to operational spacecraft and near Earth objects that may intersect the Earth. However, this project proposes to leverage the dynamics of natural orbit perturbations to significantly reduce current extreme high mission cost and create new opportunities for space exploration and exploitation. The COMPASS project will bridge over the disciplines of orbital dynamics, dynamical systems theory, optimisation and space mission design by developing novel techniques for orbit manoeuvring by “surfing” through orbit perturbations. The use of semi-analytical techniques and tools of dynamical systems theory will lay the foundation for a new understanding of the dynamics of orbit perturbations. We will develop an optimiser that progressively explores the phase space and, though spacecraft parameters and propulsion manoeuvres, governs the effect of perturbations to reach the desired orbit. It is the ambition of COMPASS to radically change the current space mission design philosophy: from counteracting disturbances, to exploiting natural and artificial perturbations. COMPASS will benefit extensive international, including the ESA, NASA, JAXA, CNES, and ASI. Indeed, the proposed idea of optimal navigation through orbit perturbations will address various major engineering challenges in space situation awareness, for application to space debris evolution and mitigation, missions to asteroids for their detection, exploration and deflection, and in space transfers, for perturbation-enhanced trajectory design.
Project
ReDSHIFT addresses the call topic PROTEC-1-2015: "Passive means to reduce the impact of Space Debris" from the H2020 Space Work Programme. ReDSHIFT will address barriers to compliance for spacecraft manufacturers and operators presented now and in the future by requirements and technologies for de-orbiting and disposal of space objects. This will be achieved through a holistic approach that considers from the outset opposing and challenging constraints for the safety of the human population when these objects re-enter the atmosphere, designed for demise, and for their survivability in the harsh space environment while on orbit. Ensuring robustness into the future, ReDSHIFT will take advantage of disruptive opportunities offered by 3D printing to develop highly innovative, low-cost spacecraft solutions, exploiting synergies with electric propulsion, atmospheric and solar radiation pressure drag, and astrodynamical highways, to meet de-orbit and disposal needs, but which are also designed for demise. Inherent to these solutions will be structures to enhance spacecraft protection, by fracture along intended breakup planes, and re-entry demise characteristics. These structures will be subjected to functional tests as well as specific hypervelocity impact tests and material demise wind tunnel tests to demonstrate the capabilities of the 3D printed structures. At the same time, novel and complex technical, economic and legal issues of adapting the technologies to different vehicles, and implementing them widely across low Earth orbit will be tackled through the development of a hierarchical, web-based tool aimed at a variety of space actors. This will provide a complete debris mitigation analysis of a mission, using existing debris evolution models and lessons learned from theoretical and experimental work. It will output safe, scalable and cost-effective satellite and mission designs in response to operational constraints. Through its activities, ReDSHIFT will recommend new space debris mitigation guidelines taking into account novel spacecraft designs, materials, manufacturing and mission solutions.