The Window Year: Why Ships Reach Mars Only Every 26 Months
Updated: 2 days ago
Mars is not always reachable. Most of the time, no ship can leave Earth and get there.
Then, once every 26 months, a door opens. On Mars, they call that a Window Year.
Why there is a window
Earth and Mars circle the Sun at different speeds. Earth needs one year. Mars needs almost two. Most of the time the two planets are in the wrong place for a ship to cross between them without burning an absurd amount of fuel.
The cheapest route is called a Hohmann transfer. A ship leaves Earth, coasts along half an ellipse around the Sun, and meets Mars on the far side. It only works if Mars is at the right angle ahead of Earth on launch day. That alignment returns about every 26 months.
Miss it, and you wait for the next one.
How long the crossing takes
With today's rockets the trip takes seven to nine months. In the world of Mítosz, set in the 2090s, the fastest crossing still takes at least four months.
The window is still there. A faster ship does not change where the planets are.
Mars Year 73
ICARUS takes place in Mars Year 73, which runs from September 11, 2090 to July 27, 2092. A sol, the Martian day, is a little longer than a day on Earth.
It is a Window Year. The dates look like this:
Ships leave Earth: Sol 115 to Sol 154
Ships arrive at Mars: Sol 232 to Sol 271
Ships leave Mars for Earth: around Sol 169 to Sol 256
For about forty sols the door is open. Then it closes for more than two years.
What it meant for Vostok
The story opens on Sol 10. A dust storm is closing in on Vostok, the Russian settlement. Moscow has sent nothing for four years.
Major Ivanov sends a distress call to Moscow. He hopes that a disaster in a Window Year will finally make Earth open its stockpiles.
The arithmetic is merciless. On Sol 10 the window is still more than a hundred sols away. Nothing can leave Earth before Sol 115. Nothing can land before Sol 232.
Help that arrives in time can only come from someone who is already on Mars.
What it means for everyone
In a Window Year every settlement on Mars is waiting for the ships. Supplies. Spare parts. People.
So every leader is a little more careful. And every lie costs a little more.
Start reading: When the Sky Turned Red, Vostok Station
Comments