Videos

14080 readers

169 users here now

For sharing interesting videos from around the Web!

Rules

Videos only
Follow the global Mastodon.World rules and the Lemmy.World TOS while posting and commenting.
Link directly to the video source and not for example an embedded video in an article.
Don't be a jerk
No advertising
Avoid clickbait titles. (Tip: Use dearrow)

founded 1 year ago

MODERATORS

[email protected]

What if we aimed the Hubble Telescope at Earth? - Minute Earth are working together with xkcd to animate "What If" questions! (www.youtube.com)

submitted 9 months ago by [email protected] to c/[email protected]

21 comments fedilink hide all child comments

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 3 points 9 months ago (1 children)

And the angular momentum is conserved.

Your choices are basically RCS thrusters or reaction wheels. Thrusters burn limited fuel. Reaction wheels are flywheels inside the satellite that you spin in the operator opposite direction to where you want to rotate. They are limited by the mass and size of flywheel, and the maximum speed you can spin it up to.

[–] [email protected] 1 points 9 months ago

electromagnets also work as the earth has a magnetic field. a pair of reaction wheels can be rotated (which yes, adds complexity) opposite directions along an axis perpendicular to the axles once they have reached saturation, effectively resetting the reaction wheels