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James Webb Status Page

jwst.nasa.gov

51 pointsmmaunder11 comments

It blows my mind how fast these things travel at cruising speed. It's completing a marathon every 21.8 seconds.

It's going almost half the speed it did yesterday (1.8km/s vs 3.5km/s). Why is that?

The target Orbit is at L2 Lagrange point, the point on the line connecting Earth and sun behind Earth, where gravitational force and centrifugal force are equal and you have a semi stable, force free orbit.

From the outside view, the telescope will orbit the sun with the sand period as Earth, so the relative speed will be 0.

To avoid the need for strong deceleration, and thus lots of fuel, shocks etc, they use a trajectory where earth gravity will slow down Webb so they arrive just right with 3 minor planned course corrections but no real burn.

So you will see the relative velocity drop continuously until wenn arrives at L2.

This is such a beautiful example of the use of math and physics to achieve something that feels impossible.

And (I think) you could potentially calculate this to a reasonable accuracy with 8th grade basic algebra? Or maybe at most basic calculus.

I read that it cannot actually even brake in the case it is going too fast. It only has a major motor pointing towards the Sun!

It’s insane how far it’s going to orbit from Earth. I didn’t realize you can orbit earth at that distance.

> The James Webb Space Telescope will not be in orbit around the Earth, like the Hubble Space Telescope is - it will actually orbit the Sun, 1.5 million kilometers (1 million miles) away from the Earth at what is called the second Lagrange point or L2.

https://jwst.nasa.gov/content/about/orbit.html

JWST won’t orbit the Earth. It will orbit around the L2 Lagrange point.

I’m a moron.

So am I. You read/learn more in a specific area and you stop being a moron (in that area). Only recently I realized the source of my frustration in my knowledge pertaining to my profession. For years I've been frustrated that I don't know about certain areas that "I should know of". I just realized that I've never actually learnt anything in those areas with enough effort. Just had a superficial knowledge, thinking that this is somehow deep. Thinking knowledge comes ex nihilo is very dangerous. It is a good point for me now, as, it turns out, there is nothing wrong with me, I just need to do my belated homework. It sounds stupid, but spans years in my example. Do the real stuff, you will have the real knowledge/skills.

Arguably it is rotating around the Earth once a year, but it will never be between the Earth and the Sun.

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