Trolls Around The Solar System (Part 3 - Mars)

The trolls have left Venus and continued their solar system tour. They have flown past Earth and their next stop is Mars, the Red Planet. What new things are they going to learn there? What new adventures await them on this planet's rocky surface? The DIY rocket is approaching Mars and the trolls are getting ready for touch down.

- Aaah! It's all red here, this planet is all christmasy! I like it! X54 said excitedly.

- That's from the iron traces, the red color you see it all comes from rust, X31 explained.

- I don't care where it comes from, I like it! 

- Did you see how smaller Mars looked from space when compared to Earth? X42 said.

- Yes, Mars is smaller than the Earth (its diameter is about half the one of our planet), meaning that gravity here is weaker (almost a third Earth's gravitational pull, 3.7 m/s2) and it's also less dense than the Earth, X31 said. But those two neighbors have a few things in common.

- Like what? X54 asked.

- Well, Mars has seasons, unlike Venus, X31 started explaining. Because its axis tilt (~25°) is similar to Earth's (23°), seasons on Mars change pretty much the same way they do on Earth; only they last twice the time they do on Earth, since Mars' orbit around the sun takes almost double time. Think about it, a year on Mars lasts about two earth-years (more specifically, one year and 322 days). 

- Are days longer than years here too, like on Venus? X42 asked.

- No, days here last only about 40 minutes more than on Earth, X31 answered. And you know what, Mars doesn't have only one, but two moons, Phobos and Deimos.

Wow! Think of a night with two moons in the sky... X42 imagined.

- And a sunset that's blue instead of orange! X31 added.

- Blue?! That would be super awesome, X42 said.

- There is such variety within our solar system, how come you can remember all these things, X31? X54 wondered.

- I have read about the solar system countless times, it's easy to remember a lot of information through repetition, especially when you enjoy the subject.

- Tell me about it, I can't even learn the multiplication charts by heart, and you have memorized volumes of encyclopedias, X31. That's not fair! X54 sounded disappointed.

- Don't worry, X54, you're not the only one having trouble with multiplication, X31 tried to comfort him.

- Hey! Enough with the math talk you two! I want to learn more about Mars, X42 complained.

- You're right, X42, X31 apologised. Let me tell you more about the Red Planet that got its name from the god of war, Mars (Ares for the Greeks). The average temperature on the planet is -80°C. In winter, temperatures around the polar caps drop as low as −143 °C, but in summer they can reach 35 °C near the planet's equator. One weird thing about Mars and its seasons is that they are more extreme in the southern hemisphere, because of its orbit's large eccentricity. The planet is closer to sun around southern hemisphere's summertime, this means that the summers here are short and hot whereas winters are long, dark and cold. The northern hemisphere seems to be more favored and experiences milder seasons.

- What about the atmosphere? X42 asked.

- Mars' atmosphere consists mostly of CO2, and because the atmosphere here is thinner, which translates into lower atmospheric pressure, the planet cannot support water in its liquid form. There are, although, the conditions that allow for water to form clouds and precipitation.

- Look! It's snowing! X42 shouted.

- Wow! That's amazing, X54 exclaimed.

- This is not regular snow guys, X31 started explaining again. The snow on the southern hemisphere, where we are now, is made from CO2. 

- You mean that if I put some in my juice, it would turn it into some kind of a sparkling refreshment? X42 asked curiously.

- Hmm, I haven't thought about that, but maybe. Although the pressure here is too low for the CO2 to dissolve in your juice, X31 sounded curious as well. What actually happens here in winter is that, as temperatures lower the CO2 is forced to freeze and condense into dry ice over the polar ice caps. When spring-time comes, temperatures rise, and dry ice sublimes. Dust and escaping water vapor form clouds just like on Earth. The fun fact is that  CO2 snow clouds can form only in the south of the planet. 

- Can I ask something?

- Of course, X54.

- When we were coming I saw a huge bulge, what was it, X31?

- Oh! you must mean Olympus Mons, the highest mountain in our solar system, about three times taller than Everest (27 kilometers high). There is also a very impressive system of valleys up here, Valles Marineris, that extends for 4 kilometers and goes as deep as 10 kilometers. The planet also has the largest volcanoes in our solar system and some explosions occur even today. The channels, valleys and gorges on Mars imply that water might have been flowing all over the planet in the past, but today it is limited in the form of ice in the poles.

- Is that a tornado I can see in the distance? X42 sounded worried.

- Yes, X31 answered. Dust storms are pretty common on Mars especially when the planet is at its closest to the sun. They travel at very high speeds (even more than 100 miles/hour), but there is no need to panic trolls, this one seems to be getting farther from us.

- I heard somewhere that you can see the northern lights on Mars, is that true? X42 asked.

- Yes, Mars used to have a magnetic field 4 billions years ago, but it is now gone. Its atmosphere was thicker too, but the violent solar wind has led lighter air molecules to escape because of the weakening of its magnetosphere. Now, the planet has low-range, umbrella-shaped magnetic fields. Most of them are found here, in the southern hemisphere and you can see the aurora effect because of them when solar wind sweeps the planet.

- I think I can see it over there, look! X42 shouted.

- It's beautiful! X54 said.

- Trolls, do you see what I see? X31 sounded surprised

Suddenly, there was a bright trail in the sky where they trolls could see the aurora phenomenon. The trail seemed to be approaching. The trolls could not believe their eyes!

- Santa?! Is it Santa?! all three of them said.

- Ho! Ho! Ho! Merry Christmas, trolls! I was looking all over the solar system for you.

- Santa? You're real? X31 was shocked.

- Of course I'm real my little science-geek troll! Santa responded. I am as real as I can get and really really tired. I was delivering presents all night and looking for you, I had one more present left in my bag and I could not go home until I found you and give it to you.

- We are getting a present? Wow! I cannot believe this! X54 was super excited.

- You are, you've been such good trolls teaching us so many wonderful things this year, I could not leave you un-rewarded for that. That's why I chose to give you this. Go on, open it!

A big box wrapped in red paper with christmas trees and candy canes was in fron of them. The golden ribbon was bigger then X54 himself. The trolls were left watching with their eyes wide open. 

- Are you opening it or what? Santa was anxious.

All three trolls got over their Christmas present, they were so excited that they shred the paper to pieces. They quickly opened the box and got its content out. It was... a robot!

- Woah! We got a robot! I have always wanted a robot helper! X31 shouted.

- It's amazing! Thank you, Santa! X42 said.

- Yes, thank you so much, Santa! X54 said.

- I think you'll find it useful in your journey. It can do all sorts of things and speak so many different languages. I'm sure you'll make good use of it. Enjoy your new present trolls and have a very happy New Year! I hope you'll get to teach us even more awesome stuff like you did during 2017. Now if you excuse me, but I am really tired and the journey back to the North Pole is quite long. I'm so happy that you loved your present, Santa said in a sweet voice.

- Thank you, Santa, we did not expect you to go through all this trouble for us. You're amazing! X31 said.

- Goodbye, trolls! Have fun and stay safe!

- Goodbye, Santa! See you next year! the trolls said as they waved goodbye.

Santa's sleigh was gone in the sky and the trolls were left checking their new, cool robot out.

- Now all we need is give him a name, X54 said.

- Let's see if those people in the comments can come up with something clever, shall we? X31 suggested.

- Ok!

To be continued...

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References

mars.nasa.gov
space.com_1
space.com_2
solarsystem.nasa.gov
wikipedia.org

*All images by @ruth-girl

Thank you so much for reading! I really hope you enjoyed this adventure. If you want to check out more troll stories, you can follow some of the links below:

• Τhe rise and fall of a star - Αn educational dialogue
• Trolls getting to space - DIY rocket chemistry project
• Trolls on the moon - Learning moon facts (part 1)
• Trolls on the moon - Learning moon facts (part 2)
• Trolls on the moon - Learning moon facts (part 3)
• Trolls on the moon - Learning moon facts (part 4)
• Trolls around the solar system (part 1 - Mercury)
• Trolls around the solar system (part 2 - Venus)

Until my next post,
Steem on and keep smiling, people!