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### Could JWST stay at L2 “forever”?

Using only reaction wheels powered by solar panel and the sunshield as a sail (in continuous active attitude control) to generate thrust from solar photon pressure in the desired direction, could JWST ...
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### 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 ...
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### Besides HST, JWST and stations, are there any examples of satellites designed for service in space?

update: I've just read these intriguing first sentence in the recently published (and paywalled) Aviation Weekly article No Second Chances On Webb Telescope Deployment: NASA has no plans to service ...
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### What is the required burn to keep a satellite at a Lagrangian point?

When a satellite reaches a Lagrangian point, it has a non-zero velocity $v_1$ because of the transfer orbit in which it had already been. What burn, say, $\Delta v$, one needs if the satellite is ...
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### Halo vs Lissajous orbit: Which station-keeping strategy to select and when?

I'm looking for a comprehensive pros and cons of the two most commonly used station-keeping types of orbits used at libration points, Lissajous and halo orbits. When would one select one over the ...
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### Can/Will the James Webb Telescope maintain its position passively?

A recent article about the telescope states (emphasis mine): Unlike Hubble, which orbits the Earth at about 340 miles of altitude, Webb will be sent almost a million miles into space, at a ...
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### What are the sources of light at L2? How will the James Webb telescope be powered?

The James Webb space telescope will be positioned very close to L2. According to JPL, Webb will have a large solar-array to power itself. I don't understand how this works, since L2 is positioned "...
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### Do Lagrangian points apply to eccentric orbits or binary systems?

The assumptions about the Lagrangian points being stable (...in the traditional meaning of the word: not moving around; they are unstable in the mathematical sense, except for arguably L4, L5) that I'...
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### Is Landsat-7's propellant resupply port “robot-ready”? (Restore-L mission)

note: the recent 2019 news Northrop's satellite refueling spacecraft launches on October 9th which is sourced from Mission Extension Vehicle Headed for Space reminded me that there may be some ...
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### Will WFIRST and JWST be able to resolve each other?

The James Webb Space Telescope is scheduled to launch in 2021 and be put in a halo orbit around Sun-Earth L2 soon after. The plan for the Wide Field Infrared Survey Telescope is a launch perhaps ...