Maybe you saw, maybe you haven't yet, but Stephen Hawking and
other scientists have recently been talking in the media about travelling to
another star system. That's fancy talk for another solar system! Like ours,
but, different, and very, VERY far away. But how is it that we are planning to
send space crafts out that far into deep space when we can't even get humans
out of Earth's own orbit? How are we able to send something that far and be
alive to witness it, if it took us over 20 years to just get a spacecraft past
Pluto? And this star system is way, way farther than Pluto relative to us.
Like, unfathomably far.
Well, as interesting as it seems, you're
probably overthinking it. If I make a rocket and launch it into space, it will
take A LOT of energy to get that rocket out of our atmosphere and into space,
because it weighs a lot and gravity is a bitch. Well, and a blessing so we
don't float away, but in this case, it's a bitch. Then, to make such a big
spacecraft move while in space also requires energy and we don't have an energy
source (yet) that realistically could allow such a craft to travel to another
star system fast enough. BUT, how would I be able to make something go faster?
Shrink it! Duh.
If I have a house and a cell phone, which
one could I accelerate, or move, the easiest? Obviously the phone, because it's
damn small in comparison. It would be able to travel the same distance as the
house with a fraction of the energy. Simple logic right?
So now think of that phone in space. How
can I get this phone to move around without a fuel source? Hmmmm.... for this,
we'll need to think back to the 1800s. Remember boats? Yeah! They float. Pretty
neat stuff, but before we knew about motors, we needed these wooden floats to
move. So they threw giant sheets up to "catch" wind and move the
boat. Worked like a charm.
So back to space, if I have a spacecraft
with no "motor" (local energy source), and I put a "sail"
on it to "catch" wind, it should move, right!? Welllll, there
isn't exactly wind in space, BUT, there is something we can use instead. THE
SUN! Yeah! The Sun emits a ton of energy everywhere and all the time. That's
the idea behind the LightSail® by the Planetary Society you may or may not have
heard about.
Okay Jay, that's great, but how can our
sun provide enough energy to push a tiny space sail boat to another star
system? Well, it can't. I mean eventually maybe but it would take forever. So
now we need something stronger than the sun. Uh oh, what could that be?
LASERS.
What's a laser but concentrated light? Now
I'm not talking about a laser pointer because that doesn't carry much energy at
all, but if we can develop a laser that has Gigawatts (1 with 9 zeros after it)
of power, and shoot it at our space sail, we could potentially accelerate that
tiny little ship to 1/5th the speed of light!
Now that may not seem fast compared to the
actual speed of light, but it's @$^#&$*
times faster than we've ever gone before.
Comments
Post a Comment