Our Place in Space: Phobos

Hello, friends!  Welcome to Our Place in Space: A to Z!  For this year’s A to Z Challenge, I’ll be taking you on a partly imaginative and highly optimistic tour of humanity’s future in outer space.  If you don’t know what the A to Z Challenge is, click here to learn more.  In today’s post, P is for…

PHOBOS

Buzz Aldrin.  He walked on the Moon.  He also has ideas about how to get humans to Mars.  We talked about one of those ideas earlier this month, and now we’re going to talk about another.  What if, rather than going straight down to the surface of Mars, we first set up a little base for ourselves on Phobos, one of Mars’s two moons.

Whenever you want to land on a planet (or a moon), you’ll have to fight against gravity to do so.  That is assuming, of course, that you want to land safely.  Crashing into a planetary body is fairly easy.  Landing safely—that’s the hard part!  You need to control your descent.  If you’re controlling your descent using rocket engines, you’re going to use up a whole lot of fuel in the process.

But as you can see in this highly technical diagram, Phobos is very small.

Okay, maybe not that small.  But still, Phobos is much smaller than Mars, and Phobos’s surface gravity is significantly less than the surface gravity on Mars.  That means a rocket controlled descent onto the surface of Phobos will use up less fuel than a rocket controlled descent all the way down to the surface of Mars.

In his book Mission to Mars: My Vision for Space Exploration, Aldrin argues that we should set up a way station on Phobos before attempting to land humans on Mars.  From this Phobos way station, astronauts could get an up close and personal view of Mars.  They could get the lay of the land without actually landing.  Using remote controlled robots, they could explore the Martian surface and prepare the way for future missions.  And on the off chance that we discover alien life on Mars (current life, I mean, not fossils), then our astronauts on Phobos could study that life from afar without risking any sort of biological contamination.

Personally, I’m not 100% sold on this idea.  I kind of feel like if we’re going to go to Mars, let’s just go to Mars.  But Buzz Aldrin is Buzz Aldrin, and I’m just some guy with a blog.  The thing about the fuel costs for landing on Phobos vs. landing on Mars makes sense to me.  And if it does turn out that there’s life on Mars, contaminating the Martian ecosystem with our Earth germs (or having Mars germs contaminate us) does become a serious concern.

But otherwise, do we really need a way station on Phobos?  Is that a necessary prerequisite to landing humans on Mars?  I don’t know.  Maybe it would be helpful.  When the time comes, maybe we really will go to Phobos first and land on Mars later.  It’s possible.

Want to Learn More?

Once again, I’m going to recommend Mission to Mars: My Vision for Space Exploration by Buzz Aldrin.  Lots and lots of ideas in that book about how we might one day travel to Mars and what we might do once we get there.

Our Place in Space: The Aldrin Cycler

Hello, friends!  Welcome to Our Place in Space: A to Z!  For this year’s A to Z Challenge, I’ll be taking you on a partly imaginative and highly optimistic tour of humanity’s future in outer space.  If you don’t know what the A to Z Challenge is, click here to learn more.  In today’s post, A is for…

THE ALDRIN CYCLER

Even in the future, space travel will be expensive.  True, new technologies should make it less expensive than it is today, but there’s one problem that will never go away, no matter how advanced our technology gets: gravity.

Anywhere you want to go in space, you’re going to have to fight against gravity to get there: Earth’s gravity, the Sun’s gravity, the gravity of other planets and moons—at some point on your journey, you’re going to have to fight against any or all of these gravitational forces.  And fighting gravity uses up fuel.  Lots and lots and lots of fuel.

And yet, despite the unforgiving and unrelenting force of gravity, human civilization will eventually spread out across the Solar System.  I’m not going to tell you it will happen in the next twenty years.  I won’t tell you it will happen in the next century, even.  But someday, it will happen.  I’m sure of it!  And so today, I want to talk a little about what the future transportation infrastructure of the Solar System might be like.

American astronaut Buzz Aldrin is, of course, most famous for being the second person to set foot on the Moon.  Aldrin is also a highly accomplished scientist and engineer.  In 1985, he did some math and discovered a very special orbital trajectory that would make traveling from Earth to Mars (and also from Mars back to Earth) far more fuel efficient.

The term “Aldrin cycler” refers to that very special orbital trajectory Aldrin discovered.  The term can also be used to describe a spacecraft traveling along that special orbital trajectory.  The initial investment to build an Aldrin cycler (the spacecraft, I mean) would be really high.  We’d probably want to build a rather large spacecraft for this, and once it’s built, maneuvering the thing into the proper trajectory would require a stupendous amount of fuel.

However, once we’ve done all that, the cycler will cycle back and forth between Earth and Mars, over and over again, pretty much forever.  Traveling to Mars would be a little like catching a train.

I was going to have the Aldrin cycler make a “choo-choo” sound, like I train, but then I realized that would be silly.  Things don’t make sounds in outer space.

Passengers would board the cycler as it flew past Earth; about five months later, they’d disembark and head down to the surface of Mars.  The cycler would then take a long journey (about twenty months) looping around the Sun before flying past Earth once more; then the “cycle” would begin again.

The trip from Earth up to the cycler would still require some amount of fuel.  So would the trip from the cycler down to the surface of Mars.   The cycler itself would also require a little bit of fuel for maneuvering thrusters; otherwise, over time, the ship could start to drift ever so slightly off course.

Obviously this is not a cost-free form of space travel, but I’m sure you can see how this could help keep the cost of space travel down.  And so I imagine in the distant future, the Aldrin cycler (or something very much like it) will be a key part of the Solar System’s infrastructure, just as trains are an important part of our modern day infrastructure here on Earth.

Want to Learn More?

Click here to see a short animation of the Aldrin cycler orbital trajectory, showing several cycles worth of Earth-to-Mars and Mars-to-Earth journeys.

I’d also recommend Buzz Aldrin’s book Mission to Mars: My Vision for Space Exploration, where Aldrin describes the Aldrin cycler (and other cool Mars related things) in more detail. Click here to see the book’s listing on Amazon.