HUMAN beings are fascinated by the idea
of alien life. Me included. So the discovery, albeit a bit
hypothetical so far, of a rocky, earth-like planet orbiting our
nearest celestial neighhbour inevitably caught the headlines and the
imagination.
Proxima Centauri is, as the name
implies, quite close to our star, Sol. A mere 4.3 light years away.
And inevitably the speculation has been about 'going there' or
'sending a probe'.
Thing is we have already arrived in a
sense. In fact we have been arriving in increasing strength every
year since the first radio transmission on earth (in the 1890s thanks
to Marconi and a shack in Chelmsford, Essex). Whether Marconi's
signals had the strength to reach Proxima is not clear.
But by now we are at the centre of a
bubble of radio waves some 200 light years in diameter, and this is
90 plus light years beyond the new planet. Does that tell us
anything?
Well maybe that the planet does not
contain any advanced technological creatures since they would
probably have heard us and responded by now. Or of course that it
does and they are so smart and so appalled by what they hear and see
that they have, perhaps wisely, decided NOT to pick up.
The point here is that what we ordinary
mortals think about as alien life is very, very different from what
our learned scientists expect. We might have little green thingies in
mind; they have anything remotely capable of replication in their
minds.
For that surely is the nature of life –
replication to survive in the given environment. In fact when dear
old Darwin postulated 'evolution' as the cause of all we see he had
no idea what the mechanism might be. It took a long time and a lot of
science to arrive at the gene and DNA. And oddly the idea of bits of
something being passed from generation to generation had been talked
about 2,000 years earlier by the Greeks. But nobody listened because,
to be frank, the idea was, let's face it, preposterous!
So what do we really know? Well that
lots of stars have planets. Frankly that should not be a surprise as
our best theory of early celestial conditions virtually guarantees
stars have planets and asteroids, stuff collides, some planets have
satellites. And our chemistry tells us that things happen in an
ordered way. So if just once out there the conditions are right then
life is a given. Of course then it has to survive but that's a whole
other ball game. Literally.
So some 4.3 light years away there is a
red dwarf (not the best candidate for life giving properties) which
is being orbited by a large lump of earth-like rock that is very
close and may be so close it is trapped into having one face
permanently facing the dwarf. While the other faces bleak, silent and
very, very cold space.
Frankly it is not the best candidate
for little green, brown or even grey men. But life? The kind
scientists talk about? Maybe. After all it has twilight zones,
between the scorch and the freeze. And scientists can theorise how
good conditions can propagate there.
But get there? Send a probe? Its 4.3
light years away. It is just possible to imagine travelling at 1% of
the speed of light. That's about 1,860 miles a second or 2,991
kilometres per second. But that's still going to be 4,300 years. When
it arrives it will take 4.3 years for a signal to tell us it has
arrived. Or did arrive. Anyway...
The problem is not whether we could
accelerate to that speed. Or control our ship that long and that far.
Given the right propulsion and long enough the answer is simply yes.
But space is not empty and at those speeds it is actually quite
crowded. Not big stuff (maybe?) but lots of dusty stuff. Fancy
hitting a grain of dust at that sort of speed? Reckon we could build
something to survive it? And do it again, and again, and...
So I'd say we are not going and indeed
cannot, short of finding the wormhole solution (Mind you I keep
reading about cranky stuff in the quantum physics environment and
sometimes I do wonder...)
If we are not going then: Do we need to
worry about 'them' coming to us? Well let's put it this way – if
they are coming shouldn't we get some interesting radio stuff ahead
of their arrival?
And won't they be batting off the
'stuff' of the universe all the way? I'm cool on this one. Our
earth-bound problems are much more immediate.
Anyway, what do we do when they turn up
in a burkini?
