Linked Questions

11
votes
4answers
4k views

Why aren't space telescopes put in GEO?

I don't know of any space telescope that has been placed in geosynchronous orbit among the communication satellites. I wonder why not? In GEO, a space telescope could use a single stationary radio ...
15
votes
4answers
4k views

What artificial satellite has the farthest orbit around the Earth?

What is the furthest Earth orbiting satellite? What is its speed and purpose?
16
votes
1answer
919 views

Why was TESS' launch window open for only 40 seconds per day?

The BBC news podcast Science in Action episode New Planet Hunting Mission covers the upcoming TESS mission between 01:00 and 07:15 with Sara Seager, TESS deputy ...
1
vote
4answers
146 views

Is GEO redundant (Geo- and Earth)? Would we call a Lunasychronous Lunar orbit LLO?

I think the title of the question Is it possible to establish a synchronous lunar orbit without using Lagrange points? is absolutely clear; it's an orbit around the Moon that is synchronous to the ...
2
votes
3answers
276 views

Why does Earth not appear to be at the focus of TESS' elliptical orbit in this video?

An excellent review of all of the considerations and work that has gone into designing TESS' orbit can be read in the ArXiv preprint A High Earth, Lunar Resonant Orbit for Lower Cost Space Science ...
3
votes
2answers
154 views

When calculating the future orbit of an artificial Earth satellite, is the Moon's gravity significant or insignificant?

Imagine a mathematician is plotting the future orbit of a satellite to be launched and put in orbit around the Earth. When they are making their calculation, is the moon so far away and the ...
8
votes
1answer
305 views

What was Sutton talking about? How to “obtain small accelerations by taking advantage of difference in gravity as a function of altitude”?

Sutton and Biblarz's Rocket Propulsion elements says in Chapter 1, section 1.2 (editions 7, 8, 9, possibly earlier as well) that: Totally different methods of producing thrust are used in ...
2
votes
2answers
180 views

How close to the moon would a flyby trip likely attempt?

For a flyby of the moon, like the SpaceX #dearMoon flight announced September 17, 2018, how close would they likely attempt to pass? Is there an average or optimal trajectory for a lunar flyby used ...
4
votes
1answer
200 views

Any news of TESS' lunar flyby; how well did go?

According to this TESS tweet: TESS is on track for a lunar flyby on 17 May at 06:34:35 UTC (2:34 AM EST). At this point, TESS will be 8,253 km from the lunar surface. In the coming days, follow @...
5
votes
2answers
208 views

Bringing an asteroid into reasonably low Earth orbit--can it be done?

Assume plenty of delta-v is available but it's very slow. At first glance it looks easy enough, get capture and spiral in. However, we have that big bully in the sky, aka Luna. Is it possible to ...
4
votes
0answers
99 views

Why have JWST in a Sun-Earth L2 halo orbit?

What is the main reason JWST will be in a halo orbit around the Sun-Earth L2 LaGrange point? There have been questions on this site that ask Why won't JWST deploy in LEO where it is potentially ...