UFOs

[prendrelemick]

When can I breathe in!

[YesNo]

I like how the ITN announcer closed out their segment on the Dome Of The Rock UFO sighting:

"We are not alone! OR ARE WE...??"

I also like what the woman from Mississippi had to say:

"We've seen 'um in Miss'ssippi like this, but never like this."

[Baudolina]

There was a thing on the TV a wee while back where some scientist said, as a remark in passing, that actually it isn't necessary to travel faster than light to achieve rapid interstellar travel. His words were something like "as you approach light-speed, the concept of distance becomes unstable and therefore distance actually shrinks once you start moving that fast."

The comment was, as I say, a throwaway one, and only tangential to the matter of the programme, but the offhand nature of the comment would make me assume that it was accepted fact amongst the scientific community. I don't pretend to understand it myself, and I wish the boffin had gone into greater detail, but there you have it!

This is the Lorentz contraction. Suppose you have a particle that is traveling extremely close to the speed of light. Because of time dilation, it may take the particle 10 seconds from its point of view to cross a distance of 30,000 light-years. Of course, from our POV it took a little longer than 30,000 years. But from the particle's point of view, time is flowing normally for it, it hasn't slowed down, and the reason it completed the trip in 10 seconds is because from its POV, that distance wasn't 30,000 light-years but something way shorter--something it could traverse in 10 seconds. So in a nutshell, from our POV time is flowing really slowly for the particle, but from its POV, space is getting "squished."

[prendrelemick]

Wheras all that is true, were you to pace out the distance travelled, in a traditional earth dweller way, The distance would be the same, only the time taken would be in dispute. (I think) Is it legitimate to measure distance by the time it takes to cover it? It raises an interesting quandry about the relationship of time distance and speed.

[The Atheist]

Just to get back to UFOs, this one was hanging around outside the other day:

[Scheherazade]

Well, if that is not an UFO, I don't know what is...

[prendrelemick]

I hope you avoided the probing.

[MystyrMystyry]

You were lucky to get such a clear photo - the red ones usually go faster

[Emil Miller]

[QUOTE=The Atheist;1016349]Just to get back to UFOs, this one was hanging around outside the other day

[The Atheist]

I hope you avoided the probing.

Yes, all clear there! I ran back inside quickly.

[Three Sparrows]

That picture looks like the red streak I saw outside yesterday. I took a picture of it but it isn't very clear. Hmm...Oh well. I guess I will just have to remain happily ignorant of what that funny light was.

[prendrelemick]

Here's a NASA fact...subject to my memory being up to it.

I would take 100 years worth of the Worlds current energy output to get a 5 tonne spacecraft to the nearest star within 50 years. That's by using the best theoretical propulsion systems. .

and then it probably wouldn't survive the trip.

[Emil Miller]

Here's a NASA fact...subject to my memory being up to it.

I would take 100 years worth of the Worlds current energy output to get a 5 tonne spacecraft to the nearest star within 50 years. That's by using the best theoretical propulsion systems. .

and then it probably wouldn't survive the trip.

This would of course be using materials and energy sources known to inhabitants of the Earth.

[The Atheist]

Here's a NASA fact...subject to my memory being up to it.

I would take 100 years worth of the Worlds current energy output to get a 5 tonne spacecraft to the nearest star within 50 years. That's by using the best theoretical propulsion systems. .

and then it probably wouldn't survive the trip.

I suspect whoever wrote that was fooling with you.

Proxima Centauri is roughly 5 light years, or 47 trillion km distant.

To reach there in 50 years would need a speed of 10% of the speed of light.

Light travels at about a billion km an hour, so we would need to be travelling at 100,000,000 km/h.

Given that current technology only allows us to travel at ~50,000 km/h, we haven't got a clue as to what kind of propulsion might be needed to attain that kind of speed. You can't make rockets go faster by building them bigger, so it's impossible to put an energy value on the question. Whether humans could withstand being propelled 20,000 times faster than ever before is moot.

Even the escape velocity of the sun (sorry to pour cold water on Mr Spock) is a measly 2,000,000 km/h, still only 2% of the speed needed to get to Proxima Centauri in time for the half-century party.

[MarkBastable]

David Icke's mob is a good example. They go a little further than just seeing flying saucers.

(For goodness' sake do NOT try to find out by reading his site - you'll burn your retinas.)

No, no - do! Also read his books. They are absolutely, untouchably fantastic. And I use the adjective in every available sense it carries. As an example of what Vonnegut characterises as slipped-gear thinking, they're unparallelled. Do not for an instant baulk at the thought that, by buying the books, you are funding a dangerous nutter. Nutters of Icke's calibre should be given as much money as they need to keep going. This stuff is so intricately, so unfalsifiably, so comprehensively insane that it beggars the creative imagination.

Honestly - the whole endeavour reaffirms my faith in the impossibility of any human being ever entirely understanding what it must be like to be someone else.