Re: UFO's
 

Galileo, I think, using the motion of Jupiter's moons. Apparently his initial calculations were reasonably accurate.

EDIT Or was it Newton?

Some brainy classical dude with a telescope, anyway.

Re: UFO's
 

the 'modern' classic experiment was the 'Michelson-Morley' one, which demonstrated that the speed of light was a constant, independant of the speed & direction of the emitter. i.e. the same speed from a star moving towards us as from a star moving away.

- the shift in frequency of the light depending on its direction relative to the observer (red shift & blue shift) is what enables us to estimate the relative speed & distance of the stars to our sun. It is the fact we observe most stars light as red shifted that forms one of the main 'proofs' of the 'big bang'.

so if the Universe really is expanding, those aliens should get here sooner rather than later, or we will all be too far apart :D

Re: UFO's
 

At the end of the day we are looking at this subject based on todays knowledge which may or may not be accurate. We cannot visualise travel to other galaxies because the distance involved would mean that we would not get there in our lifetime. But with advances in medical technology will our three score years and ten eventually be multiplied many times over. If there are many other lifeforms in existance throughout the galaxies it is highly likely that many of them are far more advanced than ours and who have life expectations so long that enduring a hundred year or more voyage might appear to them just as long as a flight to Australia appears to us.

We judge everything by our standards but could there be alien life that is many times our size, maybe several miles tall. If you look at life on Earth there are many types of life forms in many sizes. Can you realistically believe that we have every possible life form here and there are non elsewhere.

Changing the subject slightly, can you ever be sure that what you are doing at this moment in time and your total memory that you think you have are not just part of a dream (or nightmare). Is reality yet another dimension?

Re: UFO's
 

True, and where we have no knowledge, we like to fill in the gaps with our imaginations. Hence, medieval cartographers drew their maps with sea-serpents and other kinds of monster in those parts of the world as yet unexplored.

Similarly, we think about the great, unexplored ocean of space and speculate that there must surely be strange, exotic and perhaps terrifying creatures awaiting us.

We might just find that, once again, aliens and UFOs are just a fanciful doodle on the margin of our understanding. ( <--- wow, did I really say that? :spin: I should write a book... ;) :D )

Re: UFO's
 

But whilst the medieval cartographers drew the sea-serpents that did not exist, mankind did exist on the unexplored areas of the maps.

Re: UFO's
 

Only because we had already migrated there, from whatever part of the world we are believed to have originated from. The humans 'discovered' in America and Australia were not novel life forms.

Re: UFO's
 

so who's to say we only got as far as america perhaps we have got further ;)
or who's to say where we started from, perhaps we are the aliens :Yikes:

Re: UFO's
 

we will be aliens to what ever is out their - i find it pretty hard to belive that in this infinate universe i live in we are the only things and look how we ****ed it all up :) maybe all the aliens stay away for a good reason.

what we need is some seriously fast way of travelling in space and seeing whats out there and folding space seems to be the best way :)

Re: UFO's
 

as the majority of the atoms which make up our bodies were once formed in stars and may have been 'recycled' several times, you could be right ;)

Re: UFO's
 

My point about 'time' seems to have been lost...

Sorry for the repetition, I'll keep it brief ;)

Time From A Fly
From a fly's point of view, humans are very slow, large creatures which live for hundreds of generations.

Time from an Elephant
From an elephants point of view, humans are small and very fast moving creatures with a relativly short life.

BOTH.
How does the elephant see the fly and vice versa?

It's fair to say, the elephant can 'see' the fly, butthe fly cannot 'see' the elephant. The elephants movememnts are so slow, the fly may well not notice them!

So, who's to say that alien life isn't microscopic and it's been here, looked around and gone again billions of times over with nothing more to discover?


If we are talking about alien life as being *ANY* life, then yes, I would imagin there are countless lifeforms on countless planets.

If however we are talking about the kind of life form we cound communicate with, which percieves time at the same rate as us.... then that, I believe, would indicate there may be no other life in the universe

Re: UFO's
 

Galileo tried and failed using two people with lanterns a mile apart
Roemer used Jupiters moons, but didn't have accurate distances so got it as 200,000Km/s
In 1958 Froome used a microwave interferometer and a Kerr cell shutter to measure the speed of light to be 299,792.5 km/s.
These days we define a meter as 1/299,792,458 the distance light travels in one second.
In A level physics, you can get away with using 3x10^8m/s

Re: UFO's
 

:wtf: :erm: :rolleyes: :dunce: :confused: :help: I've only just got to grips with what makes up a billion (thanks Proppin :D )

Re: UFO's
 

:nworthy:

Re: UFO's
 

E=MC^2
We all know it, but do you know what the letters stand for?

E is energy
M is mass
C is the speed of light

therefore using a bit of arabic we get

C=square root (E/M)

So as speed increases, Energy and mass increases.
Something like that anyway.

Now, faster than light travel is theologically possible, although what you really do is take a short cut bye folding or warping spacetime

Re: UFO's
 

1X10^6 is a million :)
1X10^8 is 100 million (8 zeros)
m/s is meters per second (standard unit for speed)