Astronomy & spaceflight
To the Moon and Mars
Apollo showed the way, Artemis picks up the thread. And why Mars is still a whole different league.
In July 1969 Neil Armstrong and Buzz Aldrin became the first humans to set foot on the Moon. Five more landings followed until 1972, and in total twelve people walked across the lunar dust. Then, for over 50 years, nobody went back. Today that is changing: the Artemis programme is bringing humans back towards the Moon. And on the horizon waits the next, much bigger goal: Mars.
Artemis: a planned return
Artemis proceeds step by step. At the end of 2022 an uncrewed capsule flew around the Moon and back to test the rocket and heat shield. In 2026 a crew then looped around the Moon without landing. Next comes a landing near the lunar south pole. Researchers suspect water ice there, hidden in permanently dark , which could be turned into drinking water, oxygen and even rocket fuel. Unlike Apollo, this time it is not about flags and footprints but about staying: a small station in lunar is planned, and later bases on the surface.
Why Mars is much harder
Flying to the Moon takes about three days, flying to Mars takes six to nine months, depending on the launch window. That changes everything. On the way to the Moon, Earth is close enough for a rescue: after an explosion on board, Apollo 13 swung around the Moon and was back home just under four days later. On the way to Mars there is no turning back, and everything vital has to keep working for months. Then there is radiation: outside Earth's protective the crew is hit by far more cosmic radiation, and the longer the trip, the greater the risk. Food, water, air and spare parts for over two years also make the spacecraft heavy, and every kilogram costs fuel.
The return window
Earth and Mars orbit the Sun at different speeds, so the distance between them varies enormously. Only about every 26 months are the two planets positioned so favourably that you can cross over with little fuel. Miss that launch window and you wait over two years for the next one. The same applies to the way home: after arriving, a Mars crew has to hold out on the planet for around 15 months until the window for the return trip opens. A typical mission quickly adds up to two and a half to three years.
The satellite keeps falling toward the planet, but moves sideways so fast that it keeps missing it. Rule of thumb: an orbit is falling around the planet.
Realistic timelines
In films, Mars is a weekend trip, but in reality experts do the maths more soberly. First the Moon has to show that humans can live and work far from Earth for longer stretches, a dress rehearsal three days from home. In parallel, giant rockets, landing technology for heavy cargo and closed life support systems have to become reliable. Most experts therefore expect the first humans on Mars in the 2030s at the earliest. That is not bad news: the kids who will make that journey are already going to school today. Maybe you are one of them.
Exercises
0 of 6 solvedTime to try it yourself. You can't break anything, every attempt counts.
What makes a crewed Mars mission so much harder than a Moon mission?
How often does a favourable launch window for flights to Mars open?
The flight to the Moon takes about 3 days. How many hours is that?
Put the steps of the Artemis programme in the correct order.
- 1A crew loops around the Moon without landing
- 2Bases are built on the lunar surface
- 3A crew lands near the Moon's south pole
- 4An uncrewed capsule flies around the Moon and back
Between the last Apollo landing in 1972 and the year 2026, no human set foot on the Moon again. How many years lie between these two years?
Match each difficulty of a Mars mission to its consequence.