How is the speed spacecraft measured?

How is the speed spacecraft measured?

A Spacecrafts speed is Measured by using the
Doppler Effect..

It is the same effect that causes the
sound to change as a train passes you.

There will be a Doppler Radar at the base station
that will send a high frequency electro magnetic signal
to the space craft that will then return the signal to the
radar.

By measuring the Shift in frequency of the signal due to
doppler effect from the sent and received signals...we
can makeout the Speed of the Craft relative to earth.

Damn, I was going to say that but I was just guessing! Ah well, at least I know I was right ;)

Er.. right thanks Active , I see now

Did you know this already or did you look it up?

I knew that Trains use Doppler Radar to monitor speed

I should be Knowing this...

b'cos I am an Aeronautics Student...

in the future hopefully in a few years it will be measured in light speed.

it is impossible for any tangible object to go lightspeed..

although, it would be cool to travel light speed.


if you traveled light speed, and were gone for a certain length of time, which seemed very short to you, you would come back and find 50 years or so had passed, it's like you are traveling into the future, which just happens to be the present :) actually it's more like, you are traveling with time, rather than time traveling around you, so it's like you have stopped being affected by time.

You can travel at light speed..if your mass is zero...
I mean...not even the electrons of the atoms of the
molecules of the compounds of the cells of the tissues
of your body should occupy space in the universe.

That brings a hypothetical theory, that if we have our
mass in another entity that is outside universe...which
is excatly opposite in nature to our universe...such that
we relatively seem to have a negative mass in the
universe and then can fly at more than light speed
within universe.

But research on this is still premature.

And then there's the theory with quantum physics, that there is an infinate amount of paralel universes where each time we make a decision wether to do something or not it split's into another universe. What does that have to do with the above I hear you say ?

Physisit's are proving that although time travelling is probably impossible, in theory you might be able to travel through to one of these universes through the quantum foam (That is a serious term) and that these universes are not all on the same time level as us.

I've started reading up on this and sorry If it doesn't make sense, as it doesn't make a great deal of sense to me at the moment

Has anyone read "Timeline" by Michael Crichton? It basically has to do with this :)

It what was first got me interested in it. It's a good book. Also "From the corner if his eye" by Dean koontz slightly goes into it

Ian

Stephen hawking's "A Brief history of time" ..is my favourite.

I have the original edition with b&w drawings :)

Hyperspace by Michio Kaku is a very good primer.

i thought a brief history of time was a bit heavy. quite good tho.

Heres one for you:
if a car is travelling at the speed of light and the driver turns on the headlights, what happens, what would an outside observer see, what would the driver see, and how many peoples heads would explode whilst trying to calculate it all?

BOOM

there goe's mine to start you off with

What's the last thing that goes through a fly's mind as it hits your windshield?


























It's ass... :-)

And Katie comes racing into the thread and instantly lowers the tone ;)

Good on ya :D

Thank you, thank you...just trying to do my part!