Earth and Mars

Earth and Mars

What physical challenges would people face during a long-term, deep-space mission to Mars?


4 - 12


Earth Science, Astronomy, Geography

Scientists and engineers estimate it will take about eight months for a Mars mission to travel to the red planet. What impact will eight months in microgravity have on astronauts and explorers?

Existing research on personnel deployed to the International Space Station suggests that time spent in microgravity causes significant changes to human physiology. So, scientists planning Mars missions are faced with big challenges: how to protect the human body during the months-long journey to Mars and ensure astronauts are in good physical condition upon arrival.

These challenges must be met before humans can undertake a journey to explore Mars.


- Funny thing about Mars, you know, it rotates once in about 24 hours, has seasons, has polar ice caps. So on the informational surface, it feels like Earth. But you dig a little deeper and you realize it's very cold there. It's very dry there. You can't breathe the air. It is more hostile to life than any place on Earth.

- The hottest it gets on Mars is about zero degrees Celsius. And that's like high noon in the summertime on the equator. But at night, it'll get as low as -100 C.

- There is a fundamental problem that we're gonna have to deal with in terms of a Mars mission that was never the case with the Apollo program. And that is the human body and how do we protect it for long, long periods in space and on the planet's surface? We are exceptionally fragile creatures. We are very well-evolved to survive at sea level on this planet and nowhere else.

- In the absence of gravity, lots of things can go wrong. Your heart doesn't have to work as hard and so it becomes less effective. Your brain has challenges controlling your movements. The body seems to be demineralizing your bones. These are all very important to study, not just because academically we wanna know but because we wanna make sure that they're good to go when they hit the surface of Mars.

- So the physical challenge of getting to Mars is gonna be fun, right? You've been in a zero-gravity environment for some eight months, which is like being in bed for eight months. And then you reach the surface of Mars. Your coordination, your cardiovascular system, your respiratory system, all of that is all of a sudden under a gravitational load that was never there. And so the question is will you be able to survive during this crucial time of arrival?



- Lo curioso de Marte es que rota una vez cada unas 24 horas, tiene estaciones, casquetes polares. A nivel informativo, se parece la Tierra. Pero, si escarbas más, ves que allí hace mucho frío, es muy seco. El aire no se puede respirar. Es más hostil para la vida que cualquier lugar en la Tierra.

- Lo más caliente que se pone Marte es alrededor de 0 ºC. Eso es el mediodía en verano en el ecuador. Pero, por la noche, puede llegar hasta -100 ºC.

- Hay un problema fundamental que deberemos enfrentar en una misión a Marte que nunca pasó con el programa Apolo: el cuerpo humano y cómo protegerlo durante largos períodos en el espacio y en la superficie del planeta. Somos criaturas excepcionalmente frágiles. Estamos muy bien evolucionados para sobrevivir a nivel del mar en este planeta y en ningún otro lugar. EEI MISIÓN DE 1 AÑO, DÍA 157

- Sin gravedad, mucho puede salir mal. El corazón no debe esforzarse tanto y se vuelve menos efectivo. Al cerebro le cuesta controlar tus movimientos. Parece que el cuerpo está desmineralizando los huesos. Es muy importante estudiar todo esto, no solo porque queramos saberlo académicamente, sino porque queremos asegurarnos de que estén bien para cuando lleguen a la superficie de Marte.

- El reto físico de llegar a Marte será divertido. Has estado en un ambiente sin gravedad durante ocho meses, que es como estar en cama durante ocho meses. Y llegas a la superficie de Marte. Tu coordinación, sistema cardiovascular, sistema respiratorio, todo eso, de repente, está bajo una carga gravitacional inédita. Entonces, la pregunta es si podrás sobrevivir durante este tiempo crucial de llegada.

Media Credits

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Sarah Appleton, National Geographic Society, National Geographic Society
Caryl-Sue Micalizio, National Geographic Society
Sarah Appleton, National Geographic Society, National Geographic Society
Caryl-Sue Micalizio, National Geographic Society
Last Updated

May 31, 2024

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