5k views

### 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 ...
4k views

### James Webb telescope; limits to propellant lifetime?

There is a comprehensive article on Wikipedia on the James Webb telescope. It includes a statement regarding the operational lifetime being nominally five years and optimistically ten years. However ...
396 views

### Have space probe gone to unplanned destinations?

Reading this question about multiple gravity assists (Why is Voyager 1 faster than all other space probes?), it caused me to wonder if any probes have been redirected to additional (or alternate) ...
6k views

### 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 ...
2k views

### Stability of Lissajous orbits around Sun-Venus L1

How far is it from the Venus? Does Mercury gives too big perturbations for a stable Lissajous orbit?
2k views

### How many satellites can stay in a Lagrange point?

Lagrange points as I understand it are points in space between 2 objects where the gravitational pull between them is effectively equal. That makes station keeping at these points relatively easy. ...
1k views

### What is the altitude of a surface-synchronous orbit around the Moon?

A geostationary equatorial orbit (GEO) is a circular geosynchronous orbit in the plane of the Earth's equator with a radius of approximately 42,164 km (26,199 mi) (measured from the center of the ...
2k views

### Can the James Webb Space Telescope basically manage its own orbit if necessary?

In this great answer I learned that the Mars rover Curiosity can be given some tasks and it will go ahead and manage the work and navigation by itself, to at least a certain limit. The James Webb ...
1k views

### The design of the halo orbit of the James Webb Space Telescope

As I feel a little less uncomfortable with "halo" orbits, with this question, I would like to explore the practical aspects, in particular those related to the design of the James Webb Space ...
930 views

### Spacecraft Maneuvers as Intellectual Property? Wow!

In the past I had encountered a few mentions of orbits being patented (or at least applications filed) but didn't take much notice. Then I did a simple search and was blown away by the sheer volume of ...
2k views

### 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 ...
752 views

### How likely will the James Webb Telescope encounter debris trapped at L2?

Do Lagrangian points collect micro-meteorites similar to how the Pacific trash vortex collects debris? I was wondering if the James Webb Telescope will have to clear its Lagrange point before ...
306 views

### Are there some three-body orbits that can't be escaped? Can we know without propagating forever?

update: Searching for "choreographies" I found this Physics SE question which is related but different because it asks only if periodic solutions can be proven to be periodic numerically and my ...
404 views

### 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 ...
222 views

### 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 ...
442 views

### How to find Near Rectilinear Halo Orbits (NHROs)?

Looking all the good questions and answers in this site referent to CR3BP dynamics, periodic orbits, state transition matrices, etc. I wonder: what algorithm or steps do I have to follow to find the ...
263 views

### Did ISEE-3 spend a few years in a halo orbit around sun-earth $L_1$ without using any fuel?

In a related question I'm trying to find some conclusive reference(s) helping explain if some halo orbits around the sun-earth or earth-moon $L_1$ or $L_2$ locations can actually be somewhat stable (...
211 views

### Was Queqiao in a halo or Lissajous orbit? Why do sources disagree?

Wikipedia's Lissajous orbit says that sources disagree on the nature of Queqiao relay satellite's orbit; if it was in a proper halo orbit or just a Lissajous orbit. Proper halo orbits have the same ...