I am
a big supporter of space exploration. And
as a scifi writer, I spend a lot of time thinking about ways to explore the
solar system and how they could be worked into stories. Along the way I’ve come up with some ideas
for space missions which I think would be cool or would help in making humanity
a spacefaring civilization. Over a year
ago I wrote up Some ideas for small lunar landers, and I guess you could say
this is an extension of that, although these are big missions that go
everywhere else but the moon. I’m not an
engineer, so these are more back of an envelope ideas, but if you are a space
engineer and you’re looking for something to do, maybe one of these will spark something.
Deep space antenna
We
have dozens of spacecraft across the solar system, and they all need to
communicate with Earth. Most do so
through the Deep Space Network, which is a series of radio telescopes placed
across the world. So far, so good, but
as we start sending out more and more probes, there could easily be a
bottleneck in communications. My idea is
to put a big ass antenna out in space.
Part of the idea is that if we can make the antenna really big – say 100
meters in diameter – it would make it easier to get the weak signals from
extremely distant spacecraft, such as New Horizons.
Where
would you put such an antenna? I’m
thinking maybe twice geostationary orbit, so the antenna would take two days to
orbit the Earth. The reason you’d want
to put it out so far, is that in lower Earth orbit a 100 meter antenna would be
damaged by debris and the faintest traces of atmosphere would work to deorbit
the craft. Also, it would probably be
rather bright. Geostationary orbit is
full of communication satellites, and just outside of geostationary orbit is a
graveyard orbit of dead communication satellites, so I’m thinking that at twice
geostationary orbit there would be plenty of open space with little
interference.
How
would you get something that big out there?
I’m thinking you build and launch it in three parts. The first part would be the main antenna
which would be as big as can be origamied into a rocket fairing. The second part would have the solar panels,
all the electronic stuff, and the antennas to talk to the ground. The final part would be the engine to get it
into the proper orbit, and would handle all the station keeping aspects of the
mission. The best part of this idea, is
that when the fuel starts running low, you could launch a new station keeping
module to replace the old one, so that this antenna would stay functional for
decades.
Could
you fold up a 100 meter antenna to fit on a rocket? Those might already exist, I just don’t have
the security clearance to know. But if
you could only fit, say, an 80 meter antenna on a rocket, that’s not bad. But I had a crazy idea how to turn a measly 80
meter into a 100 meter. What if on the
outside of the second or third module there were preformed panels that a small
robotic arm could attach to the folded up antenna to get it up to 100
meters? A bit complicated, I admit, but
is it really that far beyond our capability, especially if we get a really kick
ass antenna out of it? Of course,
there’s no reason why we couldn’t build several of these antennas. Well, other than getting the funding for
them.
Innersystem relays
As
the author of The Moon Before Mars: Why returning to the moon makes more sense than rushing off to Mars, you can
probably tell that I’m not one of these “We have to go to Mars, now!”
people. I fully support the scientific
exploration of Mars – as well as all other solar system bodies – but my vision
of human exploration of Mars is more akin to the International Space Station
than Las Vegas. And while I think we are
probably twenty years away from humans on Mars, we do have several robots
there. That’s great, but sometimes in
their orbits, Earth and Mars will end up on opposite sides of the Sun. This means we can’t really send or receive
signals for about two weeks. During that
time, our rovers just park and probably just take some photos and wait for us
to be in contact again.
Just
for safety reasons, I don’t think we should allow this for when humans
eventually go to Mars. My solution is to
put a couple of relay satellites into orbit, probably between Venus and
Earth. So whenever the Sun blocks our
view of Mars, they could just relay the messages and we wouldn’t have to worry
if the crew is dead.
But
this only happens for two weeks every two years or so. Building and launching a satellite just for
that seems overkill. So the main point
of these satellites would be to observe the Sun. And if you have two, three, or four of these spacecraft
spread out, you can have a full view of the Sun.
Multiple asteroid flybys
I
see the real future of humanity in the Asteroid Belt. As I’ve said before, “If we go to Mars, we
get a planet. If we go to the Asteroid
Belt, we get the galaxy.” Because we can grind the asteroids up into their
component elements, and build spacecraft that we can then send to other star
systems. Before we start colonizing the
galaxy, we can use the resources from the Asteroid Belt for … just about
anything. We could mine the materials to
build the factories that would build giant solar power stations, which could
then be flown to Earth using asteroid manufactured fuel to supply all of our
power needs. For example.
But
before we can start mining the asteroids, we need to learn as much about them
as we can. We’ve already flown-by or
orbited a dozen or so asteroids, but I’d like to dramatically increase those
numbers. So this mission would be
designed to take a looping orbit through the Asteroid Belt that would let it
flyby … say at least ten asteroids.
Maybe even more. But the
interesting idea is that instead of just one, there would be three spacecraft.
I
know that the Asteroid Belt isn’t like what you see in movies where there are
thousands of rocks just rapidly flying around each other. In reality, if you were standing on an
asteroid and you were really, really, really, really lucky, you might see one
other asteroid as a dim point of light at the very edge of vision. I also know that orbital mechanics means
flying between objects in space isn’t the same as flying between points on
Earth, but I hope this idea could work.
Basically, you have three spacecraft that are mostly identical. You launch the first one, wait a week or so,
then launch the second, and wait maybe two weeks for the third. The goal, is that the A craft flies by and
gets detailed images of half the asteroid.
Then when B flies by, you adjust its path so it can image the other
half. And C fills in any gaps, or takes
a closer look at something interesting the first two found. As things stand now, if we flyby an asteroid and
see some strange surface feature, it may be decades, or centuries, before
another craft visits it to get a closer look.
With this setup, it may just be a few weeks.
The
way you’d do this would be using ion engines, which don’t have much thrust
because they go through their fuel so slowly, but since they go through their
fuel so slowly you can run them for years.
Spacecraft A would have cameras and a bunch of other instruments as well
as a small ion engine for course corrections.
Spacecraft B would have cameras and two-thirds of the instruments of A,
to make room for a bigger fuel tank because it will need to make more course
corrections than A. And Spacecraft C
would have cameras, the other one-third of instruments, and an even bigger fuel
tank because it will need to make even more course corrections.
A
possibility is that if these craft are mostly identical, you could mass produce
them and you could have four or five of these tri-spacecraft missions flying,
sending back data on dozens and dozens of asteroids. Or you might find another use for them.
Jovian moon explorer
Jupiter
has about eighty satellites, that we know of.
Four of them are big and get almost all the news, while the rest are
just small captured asteroids. We do
have a few grainy images of some of them, but the vast majority are just points
of light in telescopes. This mission
would aim to flyby as many of them as possible, because every object in the
solar system has a story but it is very unlikely there will ever be a mission
to … Pandia.
Jupiter
is much farther from the Sun than the asteroids, so you couldn’t just send a set
of the asteroid flyby craft to Jupiter.
You’d need to put on larger solar panels, for example. But it’s possible the Jupiter craft could be
a version of the asteroid craft, making the development a bit cheaper. Saturn also has some eighty known satellites,
but right now we don’t have the technology to power a spacecraft at Saturn with
solar power, we only recently got that capability at Jupiter.
One
thing both the asteroid and Jupiter missions would do is look for new asteroids
and moons. It’s likely there would be months,
even years between flybys, and one idea is that the A and B crafts would have
telescopes that could be used to search for small, dim objects in their
vicinity. If possible, there could be
unplanned distant flybys of these newly discovered objects, which would be
fantastic.
The One Light Day Mission
Voyager 1 is the most
distant human object. Launched in 1977,
it is now over 22 billion kilometers
from Earth, meaning it takes over twenty hours for its radio signals to come
back to us. Meaning, even after flying
for almost forty-four years, it’s not even one light day from us. This mission is to get that far away from us
in, say twenty years. The way it does
this is to launch the craft on one rocket, and then launch two more with
booster engines. The first one to
attach, would be as big an ion engine as can fit in a rocket. The second to attach would just be as big a
conventional rocket as can fit. This
booster fires, gets it going as fast as it can in a few minutes, then detaches. Then the ion engine fires for a decade, or
more, slowly ramping up the speed. Probably
throw in a Jupiter flyby to pick up even more.
I know it would be a challenge, but what space mission hasn’t been?
The
probe would have dust counters and magnetometers and other such instruments to
study the interstellar medium, but it would also have a telescope. Hopefully, the craft would be put on a course
to flyby a known object in the Kuiper Belt, but the telescope would be used to
look for objects too small and dim to be seen from Earth. Also, once it got out to one light day, it
would take a picture of the Sun. In such
a picture, would the Earth even be a pale, blue dot?
