[Cheiron]

Ok here goes, with risk of just talking to myself it seems...

This is a riddle in what is called "orbital mechanics", a little contemplation into laws of physics is very much needed here for solving this. The person that first replies with correct answer will win 250.000 USD and a summer resort at Cayman Islands.

Here goes:

Imagine two spacecrafts in orbit around earth. They are on same orbit and following eachother.
Spacecraft A is at the lead, Spacecraft B wants to close in on A to dock (as is frequently situation on ISS with the spaceshuttle).

What happens if spacecraft B boosts it's forward thrusters in relation to spacecraft A?

and... you can contemplate this:

What happens if spacecraft B fires it's sideways thrusters in relation to spacecraft A?

When you realize the complexity, you realize why spacecraft manouvering is not something a busdriver can do...or an ordinary airplane pilot.

Happy thinking, but think carefully now
_________________
Cheiron
______________________________
"Any scientist with respect for himself should start
the day by rejecting his own pet hypotheses".
(Konrad Lorenz)

"Wir müssen wissen
Wir werden wissen"
(David Hilbert)

[Scotsman]

Go play starhawk on main a few times and you'll get an idea on this one. I was very careful in that game to get the simulation accurate.

[Cheiron]

Hmmm, I forgot Scotsman is also interested in astronomy and astrophysics

And yups, Starhawk is a very good 2D illustration, it gets even more hairy when in 3D (or 4D as it rightfully should be called, as time is the 4th dimension), phew

Anyways... another problem in space: taking a dump ... watch this lol:

http://www.youtube.com/watch?v=HUe2HcFUPSo&feature=related

So, next time you watch a beautiful shooting star... ummm it might be... ummm
_________________
Cheiron
______________________________
"Any scientist with respect for himself should start
the day by rejecting his own pet hypotheses".
(Konrad Lorenz)

"Wir müssen wissen
Wir werden wissen"
(David Hilbert)

[Cheiron]

Ok, answer to riddle just for the record....

Let's ask astronaut Greg Chamitoff on ISS, he is flight engineer and explains the counterintuitive stuff that has to do with question at hand.

http://www.youtube.com/watch?v=-N5A0L83C_M

so ... what happens...

A) if you fire forward thrusters you move up and slowly slides behind the other spacecraft, due to you change orbit that will be higher and takes longer time, hence the falling behind.

B) in case of firing sideways thrusters you change the angle of orbit, and you will change relative position to other spacecraft each half orbit, so that you sorta float from side to side compared to other spacecraft.
_________________
Cheiron
______________________________
"Any scientist with respect for himself should start
the day by rejecting his own pet hypotheses".
(Konrad Lorenz)

"Wir müssen wissen
Wir werden wissen"
(David Hilbert)

[Cheiron]

hmmm... tonight I couldn't sleep so went for a walk, it was a nice frosty night with a clear sky... and guess what?... I saw a beautiful shooting star.... but I remembered this thread and thought.... oh well, prolly crap...
then proceeded to trod along in my nocturnal solitude contemplating the marvellous splendors of the universe and ... the more mundane phenomenons we create....hehe
_________________
Cheiron
______________________________
"Any scientist with respect for himself should start
the day by rejecting his own pet hypotheses".
(Konrad Lorenz)

"Wir müssen wissen
Wir werden wissen"
(David Hilbert)

[Alexander]

Cheiron, I have seen a shooting star and I agree it is beautiful .

I often look up at the stars........... now and then I make a wish and wonder will my wish ever come true

- Alexander -

[Anita]

Amateur Astromomer and member of Galaxy Universe and zoo project, owner of (Galileo 1100mm x 135mm Reflector Telescope/ 7-15x35mm Zoom Binocular Combo)

The standard technique for rendezvous and docking is to dock an active vehicle with a passive target. This technique has been used successfully for the Gemini, Apollo, Apollo/Soyuz, Salyut, Skylab, Mir, and ISS programs.

For this to be possible, both spacecraft must be in the same orbital plane, and the phase of the orbit must be matched. This can be achieved by one spacecraft being in a higher orbit than the other, and the lower orbit will gain on the higher orbit over time.

The active vehicle is then put on an intercept course with the target. The closure rate is then reduced by use of the active vehicle's reaction control system. Docking typically occurs at a rate of 0.1 ft/s (0.030 m/s) to 0.2 ft/s (0.061 m/s).[5]

Data captured off Wikipedia "nasa space docking"

NO prize necessay have a nice day
_________________
the Heart wants, what it wants!

[Anita]

oh and im a beautician by trade not a bus driver
_________________
the Heart wants, what it wants!

[Wicked innocence]

Well if it were me...I step on the gas...and yell get the heck out of the way, i am coming thru....but that wasnt really the question was it!