Question 1 of 10Correct: 0
🔴 From “Why Mars Is Red”1 / 10
Why does Mars's surface look reddish?
🔴 From “Why Mars Is Red”2 / 10
Why is Mars dark gray beneath its reddish coating?
Where did the canals on Mars come from?
What settled the question?
How much longer is a Martian day than an Earth day?
Why did teams switch to Martian time?
What makes a crewed flight to Mars most difficult?
What makes the Martian atmosphere difficult?
Why can't liquid water remain on Mars's surface today?
What helped Mars lose most of its water?
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Why Mars Is Red0/2Who Came Up with the Canals on Marsin the app0/2How Martian Days Differ from Earth's0/2What Is Keeping People from Flying to Marsin the app0/2Was There Water on Mars0/2
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Answers and explanations10 questions
- Why does Mars's surface look reddish? It is covered in dust with iron oxidesIron in the rocks oxidized, and wind spread the rusty dust across almost the whole planet.From “Why Mars Is Red”
- Why is Mars dark gray beneath its reddish coating? Unoxidized basalt lies beneath the dustRust covers the top layer, while dark gray basalt remains below.From “Why Mars Is Red”
- Where did the canals on Mars come from? From translating a word meaning a natural waterwayIn English, the meaning implying human-made structures was chosen.From “Who Came Up with the Canals on Mars”
- What settled the question? Images from interplanetary spacecraft in the 1960sOne series of photographs overturned half a century of observations: there were no lines.From “Who Came Up with the Canals on Mars”
- How much longer is a Martian day than an Earth day? About forty minutesA small difference - until you have to live by it: after two weeks, the workday has moved to the other half of the day.From “How Martian Days Differ from Earth's”
- Why did teams switch to Martian time? To make use of sunlight for the solar panelsInstructions had to arrive in the Martian morning, or the vehicle would sit idle for an entire sol.From “How Martian Days Differ from Earth's”
- What makes a crewed flight to Mars most difficult? Radiation, landing a heavy mass and returningSpacecraft land there regularly, but their mass is measured in tons, while a crewed spacecraft would be tens of times heavier.From “What Is Keeping People from Flying to Mars”
- What makes the Martian atmosphere difficult? It is too thin for parachutes and too dense to ignoreThat is why complex landing systems are used for rovers, but they do not scale to large masses.From “What Is Keeping People from Flying to Mars”
- Why can't liquid water remain on Mars's surface today? The thin atmosphere makes it boil and freezeAt very low pressure, water on Mars's surface boils from lack of pressure and immediately freezes.From “Was There Water on Mars”
- What helped Mars lose most of its water? Solar wind stripped the atmosphere without a magnetic shieldAfter Mars lost its global magnetic field, the solar wind began carrying away its atmosphere, and Mars lost water with it.From “Was There Water on Mars”