Category: Mars (2017/2018 Mission)

Sciency Words: Geologic Periods of Mars

~ J.S. Pailly ~ Leave a comment

One of the reasons I write this Sciency Words series is to introduce you to terms that I know (or at least suspect) we’ll be talking about in upcoming blog posts. Right now, I’m just getting started with my special mission to Mars series, so I think this is a good time to introduce you to not one but four interesting scientific terms.

Today, we’re looking at the four major periods of Mars’s geological history (based primarily on this article from ESA and this article from the Planetary Society).

PRE-NOACHIAN MARS (4.5 to 4.1 billion years ago)

This would have been the period when Mars, along with the rest of the Solar System, was still forming.

NOACHIAN MARS (4.1 to 3.7 billion years ago)

This period was characterized by heavy asteroid/comet bombardment, as well as plenty of volcanic activity. Most of the major surface features we see today formed during this time: the Tharsis Bulge, Valles Marineris, several of the prominent impact basins in the southern hemisphere, and also the vast northern lowlands—or would it have been the northern oceans? Also valley networks that formed during this time look suspiciously like river channels.

HESPERIAN MARS (3.7 to 3.0ish billion years ago)

Around 3.7 billion years ago, it seems asteroid and comet impacts on Mars died down, and volcanic activity kicked it up a notch. We also see a lot of surface features called “outflow channels” corresponding to this time, rather than the river-like valleys that appeared during the Noachian. These outflow channels may have been created by sudden and violent floods, which may have been caused by melting ice dams releasing lake water.

AMAZONIAN MARS (3.0ish billion years ago to today)

The Amazonian Period began when the northern lowlands, specifically a region called Amazonis Planitia, was “resurfaced,” covering up any impact craters or other surface features that may have been there before. Mars experts disagree about when this happened, but most estimates seem to be in the neighborhood of three billion years ago. Any obvious volcanic or geologic activity ceased during the Amazonian, and for the most part all of Mars’s water has either frozen solid or evaporated into space.

On Earth, if you want to talk about the age of the dinosaurs, what you’re really talking about is the Mesozoic Era, which is subdivided into the familiar Triassic, Jurassic, and Cretaceous Periods. And so if you’re looking for dinosaur fossils, you need look for Mesozoic Era rocks.

At this point we only have a rough sketch of the geologic history of Mars. We don’t know enough to make the kinds of divisions and subdivisions that we’ve made for Earth. But if you want to go looking for Martian dinosaurs (by which I mean fossilized Martian life of any kind, even if its only microbial) then I can tell this much: look for Noachian and Hesperian aged rock formations. Those are the rocks that would have formed back when Mars still had oceans and lakes and rivers (or at least random, violent floods).

At least, landing near some Noachian and/or Hesperian rocks seems to be a high priority for NASA’s Mars 2020 rover.

Molecular Monday: Making Rocket Fuel on Mars

~ J.S. Pailly ~ 2 Comments

Today’s post is part of a bi-weekly series here on Planet Pailly called Molecular Mondays, where we take a closer look at the atoms and molecules that make up our physical universe.

As most of you now know, I am on a totally-for-real, not-making-this-up mission to visit the planet Mars. Now if you’re planning a mission to Mars, one of the first things you need to figure out is how to get back to Earth. Unless you’re not planning to come back, which is apparently an option.

But if you do want to come home, you’ll probably need to refill the fuel tanks of your spaceship using only the natural resources Mars provides. Believe it or not, this is surprisingly easy to do using a process called the Sabatier reaction (discovered in the early 20th Century by French chemist Paul Sabatier).

In the Sabatier reaction, hydrogen and carbon dioxide mix together to produce methane, with water being produced as a byproduct. The chemical equation looks like this:

CO2 + 4H2 –> CH4 + 2H2O

Liquid methane makes a decent rocket fuel, but you still need an oxidizer. To get that, all you have to do is zap that byproduct water with electricity, creating oxygen and hydrogen.

2H2O –> 2H2 +O2

Liquid oxygen is pretty much the best oxidizer you can get, and the “waste” hydrogen can be put back to work keeping the Sabatier reaction going.

I first learned about the Sabatier reaction in Robert Zubrin’s book The Case for Mars, coming soon to my recommended reading series. The only problem, according to Zubrin, who was writing in 1996, is hydrogen. Mars’s atmosphere is almost completely CO2, but Mars is severely depleted of hydrogen. Zubrin’s solution in his book is to import hydrogen from Earth (still cheaper than trying to ship rocket fuel to Mars).

But since 1996, we’ve learned that Mars has more water than previously thought, most of it frozen just beneath the planet’s surface. So when I read about the Sabatier reaction again, this time in Elon Musk’s paper “Making Humans a Multi-Planet Species,” published in 2017, the hydrogen problem was no longer a problem. We can get it through the electrolysis of Martian water.

Of course for my own Mars mission, I don’t have to worry much about rocket fuel. My spaceship is fueled by pure imagination! But still, if something were to go wrong with my ship, it’s good to have a backup plan.

Sciency Words: Delta-v

~ J.S. Pailly ~ 4 Comments

Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us expand our scientific vocabularies together. Today’s term is:

DELTA-V

Okay, it might be a bit foolhardy of me to try to tackle this term. This is actual rocket science, and I’m nowhere close to being an actual rocket scientist. But this is still far too important of a concept for me to ignore, so I’ll do my best.

The simplest definition of delta-v (often represented mathematically as ∆v) is that it equals your total change in velocity. So if you’re driving along at 25 miles per hour and then accelerate to 65 mph, your delta-v equals 40 mph. And if you decelerate from 65 to 25 mph, your delta-v once again equals 40 mph.

Things start getting interesting when you consider delta-v to be cumulative. So if you start off at 25 mph, accelerate to 65 and then drop back down to 25, your total delta-v equals 80 mph (40 mph + 40 mph).

In rocket ship design, the term delta-v is used as a sort of proxy for how much thrust your engines are capable of and how much fuel you’re carrying. You might also consider the kinds of gravity assists or aerobraking maneuvers you can use to augment your delta-v without expending additional fuel.

This is where the math starts to get complicated, but if you can calculate how much delta-v your spacecraft is capable of, then you’ll know where you can go in space. And if you know where you want to go in space, you can figure out how much delta-v it’ll take to get there and build your spaceship accordingly.

I first learned about delta-v from a video game called Kerbal Space Program. It’s a fun and sometimes frustrating spaceflight simulator that does a reasonably good job approximating how real life space exploration works. Unfortunately I was never very good at it. The scenario in the comic strip above… I made that mistake a lot.

But hopefully I’ve learned my lesson well. I’d hate to run short of fuel during my upcoming totally-for-real, I’m-not-making-this-up trip to Mars (stay tuned!).

Links

The Tyranny of the Rocket Equation from NASA.

Can Kerbal Space Program Really Teach Rocket Science? from Scott Manley (well known for his YouTube tutorials on K.S.P.)

How to Use Kerbal Space Program to Teach Rocket Science from Digital Media Academy.

Six Words You Never Say at NASA from xkcd.

I’m Going to Mars!

~ J.S. Pailly ~ 4 Comments

I’ve done stunts like this before here on Planet Pailly. My favorite example is that time I spent a few weeks on the surface of Titan, Saturn’s largest moon. I was totally there. For real. I walked around in Titan’s icky tholin mud and I figured out how to fly in that thick, soupy, tholin-rich atmosphere. I even befriended a methane-lake monster.

But that was only a short, two-week adventure. What I’m planning now will be much longer (and if I’m going to make this in any way believable, much more research intensive). Some of you may have guessed a while ago where I’m going based on this cleverly cryptic post. But now I can make the announcement officially:

I will be spending the next two months (maybe longer) living on the planet Mars.

To be honest, I’ve always felt a little embarrassed by the fact that I do not know much about Mars, or at least not as much as a space enthusiast/Sci-Fi writer like me should know. The problem is that there’s just so much more information out there about Mars compared to any other planet in the Solar System (besides Earth). And thanks to all the robotic exploration taking place right now on the Martian surface or in Mars orbit, new discoveries seem to come out every week or sometimes even every day.

That’s a lot of knowledge to sift through. It can get pretty intimidating. So my goal for this mission is to really immerse myself in everything Martian so that I can get to know the Red Planet better.

P.S.: There is one possible problem. Even though I’ll be living on Mars, I still have to work my day job back on Earth. That’s going to be quite a long commute!

Sciency Words: Aldrin Cycler

~ J.S. Pailly ~ 2 Comments

Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us expand our scientific vocabularies together. Today’s term is:

ALDRIN CYCLER

The term cycler can refer to two different but related things in orbital mechanics: an orbital trajectory that continuously and perpetually cycles between two planets, or a spaceship that’s been set on such a continuously, perpetually cycling trajectory.

The mastermind behind this idea is none other than the famous Buzz Aldrin, astronaut extraordinaire. Turns out Dr. Aldrin is more than just a pretty face. In 1985, Aldrin proposed using cyclers to transport equipment and personnel to and from the planet Mars. After crunching the numbers, physicists at NASA’s Jet Propulsion Laboratory confirmed that Aldrin’s idea would work.

The cycler trajectory Aldrin proposed is now known at the Aldrin Cycler. Aldrin’s plan would actually use two spaceships, one for outbound journeys to Mars and another for inbound trips returning to Earth.

According to Aldrin’s book, Mission to Mars: My Vision for Space Exploration, the outbound cycler ship would take roughly six months to reach Mars from Earth; the inbound ship would take about the same amount of time to reach Earth from Mars. Both ships would then spend the next twenty months looping around the Sun to catch up with their home planets and start the cycle again.

Presumably the ships would only carry human passengers during the shorter six-month legs of their respective journeys. The rest of the time, they could just fly on autopilot or remote control.

If the Aldrin Cycler proposal or something similar were implemented, traveling to and from Mars would be sort of like catching a train, with boarding taking place regularly every twenty-six months. I’ve even found a video showing what these cyclers might look like.

Okay, that’s actually an anime that I liked when I was a kid. We don’t have to make cycler ships look like trains (though we totally should).

The major drawback with the cyclers is that the upfront cost of building them will be enormous; however, if we’re serious about establishing and maintaining a permanent human presence on Mars, these cyclers would easily pay for themselves in the long run. The laws of orbital mechanics keep them going, so they’d require little to no fuel.

And since a cycler could keep cycling for decades or centuries or even millennia (in theory, they could go on forever, or at least until the day the Sun explodes), we Earthlings would always have guaranteed access to Mars, and our Mars colonists would always have a guaranteed means of getting home if they needed it.

What Am I Researching?

~ J.S. Pailly ~ 11 Comments

I have a fun special project in the works for this blog. I don’t want to say too much yet, but some of my research materials arrived last week and I’m getting pretty excited about it.

As you can see, I have some reading to do. Add to that a few other books which were already in my possession…

Also, I picked up something special at the grocery store.

So can you guess where I’m planning to take my imaginary spaceship next?