ISS and Space-related discussion

[Sackmycook]

The speed has declined to 1.09 miles per sec from 1.11 this morning. Since, afaik, there is zero drag/resistance in space, why is it slowing ?

 

[The Bear78]

The speed has declined to 1.09 miles per sec from 1.11 this morning. Since, afaik, there is zero drag/resistance in space, why is it slowing ?

Gravity.

 

[Sackmycook]

Of course.......silly me

 

[The Bear78]

I suspect that it will continue to decrease as it nears Lagrange Point 2 (L2). Slowing down with rockets means extra fuel weight which then needs even more fuel to get off the ground...
Bizarrely, the craft needs fuel for occasional burns to stay in "orbit" around L2 as there isn't actually anything there to orbit around.

 

[JOG]

Great link @Loz thank you

 

[Skyliner33]

I suspect that it will continue to decrease as it nears Lagrange Point 2 (L2). Slowing down with rockets means extra fuel weight which then needs even more fuel to get off the ground...
Bizarrely, the craft needs fuel for occasional burns to stay in "orbit" around L2 as there isn't actually anything there to orbit around.

Wont the telescope be orbiting the Sun at a distance 193000 miles more than the Earth does? That’s my understanding of the L2 orbit.

 

[Loz]

They need to under thrust so as not to overshoot its orbit as it is not capable of turning around to slow down as this would expose the telescope to the sun.
instead they with do a number of under burns.

 

[The Bear78]

They need to under thrust so as not to overshoot its orbit as it is not capable of turning around to slow down as this would expose the telescope to the sun.
instead they with do a number of under burns.

If they overshoot something's gone seriously wrong!

Wont the telescope be orbiting the Sun at a distance 193000 miles more than the Earth does? That’s my understanding of the L2 orbit.

L2 is 930 000 miles but even though the combined gravitational pull of the Sun and the Earth will theoretically maintain an object at this point it isn't completely stable and will drift eventually.
However, L2 is in constant shadow which isn't much good for solar power so the JWST, along with a few existing probes will orbit around L2 so it will still receive solar energy.

(This is only what I've read!)

 

[Skyliner33]

If they overshoot something's gone seriously wrong!


L2 is 930 000 miles but even though the combined gravitational pull of the Sun and the Earth will theoretically maintain an object at this point it isn't completely stable and will drift eventually.
However, L2 is in constant shadow which isn't much good for solar power so the JWST, along with a few existing probes will orbit around L2 so it will still receive solar energy.

(This is only what I've read!)

Thats my understanding, but it was the fact you wrote "as there isn't actually anything there to orbit around" that puzzled me, as it will be orbiting around the Sun.

 

[Loz]

Deployment video

 

[Ghost]

 

[Ghost]

The ISS will be passing over the UK tonight at

21:32 (Bright)

23:06 ( incredibly bright )
@JOG

 

[JOG]

The ISS will be passing over the UK tonight at

21:32 (Bright)

23:06 ( incredibly bright )
@JOG

Nice one @Ghost

 

[JOG]

Argh - cloud cover!!!!

 

[Roberts83]

No cloud cover here in kettering, be looking later then.

 

[JOG]

No cloud cover here in kettering, be looking later then.

Hoping for a good view later now the rain has passed

 

[Howzat]

I think those times are UTC, so add 1 hour.

ISS Tracker

 

[JOG]

I think those times are UTC, so add 1 hour.

ISS Tracker

So, I should be craning my neck at 00:06 rather than 23:06?

 

[Howzat]

According to that tracker its over the Atlantic now so I dont think it will be 00:06. Looks like somewhere between 23:15 - 23:30 for us.

 

[JOG]

Just seen it!