Spacecraft Graveyard

[Nibb31]

13 hours ago, LordFerret said:

Oh come now, Wiki has the basics of this information, starting with its mass.

That's not enough to calculate drag, and remember that the station is tumbling, so you don't know the attitude.

But the main unknown is the atmosphere. For the same reason we can't do weather predictions beyond a few days, we can't predict the density of the upper atmosphere, for which our models are much more basic, several weeks in advance, and around the entire globe. Any approximation early on produces uncertainty that gets bigger in the future, to the point where the prediction is meaningless.

Remember that the station covers 400km in one minute, so any meaningful prediction would have to be precise to at least a minute or two. It's simply impossible to get to that level of precision several weeks in advance.

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A single solitary little satellite, such complex math, so many variables, and we're to believe climatologists can model and give concrete answers on climate change. I'll sit back and enjoy my coffee now.

I'll bite. Climate change isn't a prediction, it's an observation. Most of the predictions have seriously underestimated the problem because climate is complex and chaotic and computational models are always simplified. Also climate is not weather.

Edited October 30, 2017 by Nibb31

[Green Baron]

I'll bite as well : really, lumping together geodynamics and a tumbling aluminium can doesn't address neither problem :-)

Ok, i once read about the entry corridor for the return of the Apollo missions and how they performed several maneuvers to narrow it down from several thousands a few hours before to a cone of a few miles in the final minutes. Y'all know that better than i do.

A low orbit takes ~1.5 hours, distance travelled is >40,000km. To calculate the precipitation :-) one needs an atmospheric model through all the altitudes including air densities and compressibility as well as the weight and the aerodramatics of the can. There are several models for the first, but the latter depend on weight, the cross section to the flow, density and speed. A small change in either of these induces a change for rest of the trajectory. Is the tumbling chaotic ? When do parts fall of and how does this change the other quantities and air drag coefficient and so on ? I doubt this can be calculated, you'd need additional info like how corroded are things and so on. Impossible to obtain. So the error and the cone of travel remains big and long.

It seems to me that giving more hints than a rough estimation of the geographic area a number n of orbits before the fireworks is reading tea leaves. So we'd have n * 1.5h of pre alert time to prepare the photo apparatusses :-)

Edited October 30, 2017 by Green Baron

[ARS]

Somehow this reminds me of Ironbottom Sound

[Urses]

Somehow this remainds me on german craftsman... "You have something brocken? No problem, we will come somewhere between lunch on Juno and afternoon on September, please stay tuned and be at home there!"

The big problem is all calculated predictions are like a near-miss, it may be somewhere there but slightest changes in inperplanetary or planetary Weather changes the predictions as far they are as more to be unrealistic.

It is like close they eyes and throw a bowlingball upwards. Now predict the chance to be hit... A simple drunk bird can change this from "Full pants" to "realy bad headache"...

Funny Kabooms 

Urses

2 hours ago, Green Baron said:

the aerodramatics of the can.

Realy beautiful term! I absolutely have to steal it

[Green Baron]

5 minutes ago, Urses said:

Realy beautiful term! I absolutely have to steal it

Take it. License is wtfpl ;-)

[Urses]

3 minutes ago, Green Baron said:

Take it. License is wtfpl ;-)

I think we need a Forum conformed term for the license:

WINK -> what in name (of) kerb....