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### What is the "mass" of a Lagrange point?

Of the five Lagrange points, L4 and L5, as stable points, can be orbited by asteroids, satellites, and any other useful or interesting object. Assuming two-body motion however, calculating orbits with ...
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### Google maps for Space exploration

Google Maps Can Google Maps for Space Exploration be defined similar to our planet Earth? I.e Planet Mars exploration, Moon exploration, International Space Station (ISS) journey and other planets of ...
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### Are large halo orbits around L₁'s and L₂'s preferred over small orbits for reasons other than geometry?

There have been many examples of the placement of satellites in orbits around Lagrange points, most have been sun-earth and earth-moon $L_1$ and $L_2$ due to their proximity to earth. In each case ...
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### How to best think of the State Transition Matrix, and how to use it to find periodic Halo orbits?

I'll state my mathematical question about the state propagation and state transition matrices first, then show you a simple problem for which I would like to use these concepts to generate a densely ...
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### What is the difference between halo orbits and Lissajous orbits?

The Wikipedia articles for halo orbit and Lissajous orbit leave me wondering how these two orbits are different from an orbital mechanical point of view. Could they be discussed together here, so I ...
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### Could the Lunar Lagrange Points work for space telescopes?

Every orbit in space has its pros and cons. Low Earth Orbit has accessibility but frequent eclipses whereas a Solar Lagrange Point is clear and stable but distant. In the case of the Lunar Lagrange ...
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### Two-body problem VS Three-body problem Applications

The two-body problem deals with two bodies under certain assumptions while the restricted three-body problem deals with three bodies where one has a negligible mass (i.e. spacecraft or comet) I was ...
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### Variation of restricted 3 body problem

I'm in the process of programming a space game which will involve a 3-body system. I'm thinking of making a simplified version of the restricted 3 body problem where: Body A is fixed in space, Body B ...
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### Roughly how many kinds of closed or periodic orbits are there in the circular restricted three-body problem?

Question: Roughly how many kinds of closed or periodic orbits are there in the circular restricted three-body problem? Has anyone made an attempt to enumerate and classify/categorize them? Notes: If ...
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### Can I observe a Venus transit before 2117 from a spacecraft in the Earth-Moon neighbourhood?

The Astronomy SE side of things is clear: The next Venus transit is in 2117. Good things they come in pairs, the 2004 had too many clouds for me, but 2012 was excellent. That means I will not see a ...
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### JWST Halo Orbits for Dummies: can halo orbits be usefully approximated by Simple Harmonic Motion?

Halo Orbits for Dummies: can halo orbits be usefully approximated by Simple Harmonic Motion? I am an undergraduate in the Kerbal Academy of Astrodynamics. Patched conics have given me an intuitive ...
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### L2 point in multi-moon system

For an SF novel, if there were two large moons orbiting a planet, let's say one moon the size of Earth's moon and the 2nd moon about 20% larger, and the planet roughly the size of the Earth, would the ...
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### Is a solar free-return trajectory possible?

I'm coining a new phrase: "Dyson circuit". Is it possible, with current solar orbital capabilities (see Parker Solar Probe), to drive artificial satellites in a free-return trajectory around the Sun? ...
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### Can mascons have Lagrange-like points? In principle? At the Moon?

Background Lagrange points are a mathematical consequence of the The Circular Restricted Three Body Problem (CR3BP or CRTBP); two massive bodies orbiting around their center of mass and a third ...
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### How to prepare for an interview for a Pure Mathematics position at ISRO's Space Application Center?

I have completed a Master's in Pure Mathematics. I have read topics like Abstract Algebra, Linear Algebra, Functional Analysis, Topology, Cryptography, Course in C++, etc. Recently I found an ...
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### Can L3 have halo orbits?

I've recently said you see one co-linear libration point, you seen 'em all. That's what I always say and while halo and other orbits associated with Sun-Earth L1 and L2 work similarly, L3 is 2 AU ...
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### Which notes and/or books on mathematics, physics, 3D geometry preparatory to the study of orbital dynamics?

I have a master's degree in aerospace engineering and I'm preparing for job interviews for orbital mechanics/space flight dynamics engineer positions and I need material about maths, physics, 3D ...
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### Is it obvious or easily-proven that L4 and L5 must be in the parental orbital plane?

Looking at the question and answer and diagrams from Are Lagrangian points associated only with the smaller body? got me wondering. L4 and L5 each form an equilateral triangle with the two main ...
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### How to get Ltool by Martin et.al?

I am just starting work on dynamics of CRTBP. Over several papers I see that "Ltool" is used for trajectory design, But I am unable to find over internet. Can somebody help me to identfy how to ...
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### How do I construct halo orbits around the Sun-Earth L2 point in GMAT? What should the state vector of the spacecraft be?

I am new to trajectory design, and have been using GMAT to learn it since it's free, unlike STK. I have been trying to design a script that takes a spacecraft from Earth orbit to a halo orbit around ...
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### Distant retrograde Orbit in CR3BP Question

How can i calculate the initial vy0 component for a distant retrograde orbit in Sun-Earth CR3BP around Earth?
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### Where is Artemis on this Earth-Moon three-body bifurcation plot? Where's the near-rectilinear halo orbit for example?

Below is a $\mu = 0.01215$ bifurcation plot from E. J. Doedel, E.J. et al's Elemental periodic orbits associated with the libration points in the circular restricted 3-body problem International ...
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### Difference between approach maneuvers to the insertion points of halo and Lissajous orbit?

I have read that spacecraft use two mid-course corrections to approach the Lagrange point, then do a final orbital insertion maneuver to enter into a halo orbit. Are there any specifics about this ...
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Following up on a previous question about the classification of periodic orbits, how can they be constructed, especially the planar Lyapunov family, around libration points $L_1$ and $L_2$? And how ...