Linked Questions

15 votes
1 answer
18k views

What is a near rectilinear halo orbit?

A proposed option for the lunar orbit of a Lunar Orbital Platform-Gateway (formerly known as Deep Space Gateway) is a near rectilinear halo orbit, or NRHO. This excellent answer discusses the ...
uhoh's user avatar
  • 149k
9 votes
3 answers
2k views

What asteroids have the least delta-v to reach?

I think the question needs very little clarification - specific asteroids and/or their asteroid orbit type would answer it. My own interest is in what would best suit targeting for asteroid mining on ...
Ken Fabian's user avatar
  • 1,042
11 votes
1 answer
3k 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 ...
uhoh's user avatar
  • 149k
10 votes
2 answers
931 views

How many SpaceX 2nd stages are in heliocentric orbits?

I can think of one particularly famous SpaceX 2nd stage in heliocentric orbit that even has its own website: https://www.whereisroadster.com/ and I know one was used to send DSCOVR towards Sun-Earth ...
uhoh's user avatar
  • 149k
10 votes
2 answers
3k 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 ...
Ng Ph's user avatar
  • 2,724
5 votes
3 answers
2k views

How do spacecraft reach Lagrange points?

As I understand, to reach a Lagrange point the spacecraft would need to slow down. Also, can spacecraft passing nearby Lagrange points get captured within the point?
Bruce Vici's user avatar
12 votes
1 answer
1k views

Low Energy Transfer within Earth-Moon system

Practical aspects of a total low energy transfer to the Moon have been seen in missions like GENESIS, which uses Weak stability Boundary legs of Earth and Sun to reach ESL-2. This four body model ...
Kuldeep Barad's user avatar
3 votes
1 answer
715 views

Rendezvouses in halo or lissajous orbits

If a spacecraft was in an EM-L2 halo/lissajous orbit, and another craft would was going to approach EM-L2 a few days later, could they rendezvous immediately or is there a limitation when the second ...
Bob516's user avatar
  • 6,927
2 votes
0 answers
411 views

Did DSCOVR travel "along the stable manifold of its future SE L1 Halo orbit" to get there?

I just wrote (and have since removed) the following paragraph in this answer to How many times do you have to circle the Earth to break orbit?: As can be heard in this video SpaceX's launch of the ...
uhoh's user avatar
  • 149k
1 vote
0 answers
98 views

How is it possible to connect trajectories at a Poincare section using the "bisection" method?

When constructing a heteroclinic connection (a connection between two different periodic orbits at two different libration points), the stable and unstable manifolds of two different libration points ...
John's user avatar
  • 1,377