Linked Questions

42
votes
5answers
9k views

Why are so many space telescopes placed in LEO instead of at Lagrange Points? And why do we hear about Hubble more than any Langrange-orbit telescope?

Here is the list of every space telescope launched by different space agencies - List of space telescopes. Most of the listed telescopes are placed in Lower Earth Orbit (about 95% of them). It's ...
14
votes
4answers
2k views

Why are JWST optics not enclosed like HST?

The Hubble Space Telescope encloses its primary and secondary mirrors in a tube. The James Webb Space Telescope has no tube around its optics, which obviously leads to significant mass savings. Does ...
6
votes
4answers
578 views

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 ...
10
votes
2answers
908 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 ...
9
votes
1answer
837 views

What happens to JWST after it runs out of propellant?

JWST will be orbiting L2 which is unstable equilibrium thus will require propellant for station keeping. JWST will carry propellant for 5-10 years. What will happen once it runs out of propellant? ...
7
votes
2answers
599 views

What plane will DSCOVR’s orbit be in?

According to the “NASA Earth Science Instruments” section of noaa.gov's DSCOVR page, DSCOVR will make unique space measurements from the first sun-Earth Lagrange point (L1). ... 1.5 million ...
6
votes
2answers
533 views

How much of the sky can the JWST see?

According to the JWST FAQ: To turn and point at different objects in space, Webb uses six reaction wheels to rotate the observatory. The reaction wheels are basically flywheels, which store angular ...
4
votes
1answer
132 views

Can a Space Telescope orbit so it was always in the shadow of the Earth?

Imagine you have a space telescope that had temperature sensitive instruments. (Like the Spitzer Space Telescope). In order to maintain a cool temperature - you want it always to orbit in the shadow ...
3
votes
1answer
112 views

How will JWST maintain its elliptical orbit around L2?

I understand that JWST will have a vertical elliptical orbit around L2, but what I don't understand is how the telescope will actually maintain an orbit if there is no body in L2 to actually orbit ...
4
votes
0answers
92 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 ...
3
votes
1answer
68 views

Orbit ephemeris or visualization for the BepiColombo mission?

Where is it possible to see the progress of the BepiColombo mission in terms of ephemeris and or graphical visualisation? I should add, I've checked JPL Horizons, though its not clear how to specify ...