Exploring Mars

Image of Mars by the Hubble Space TelescopeHuman exploration of Mars has been a dream of writers and scientists for many years. The dream drew inspiration from colorful reports that astronomers had seen irrigation canals or seasonal vegetation on Mars. Today, of course, we know that the planet is colder, dryer, and windier than the harshest desert on Earth: No farmers, canals, or crops are anywhere to be seen. But is Mars entirely lifeless? Could it support a human outpost? To find out, many believe, we must set foot on its dusty soil. And that can’t happen until we know what it takes to bring people to Mars—along with many tons of supplies and shelter. Read the text aloud
A 360° view around one of the MER mission Mars roversWith the help of unmanned spacecraft, in the past half-century we’ve learned quite a bit about reaching Mars and working there. The first such spacecraft simply cruised past the “red planet,” snapping pictures along the way. The next generation entered into orbit around Mars, ultimately mapping its entire surface. A third generation reached the planet’s surface, telling us about its environment and showing us its rocky plains. Now a fourth generation of mechanical Martians is roving about the red planet, exploring craters and searching for signs of past or present life. Read the text aloud
Launch of an MER mission rocket with indicators of its speed and accelerationAs you learned in the investigation on orbits, the Earth (and everything on it!) circles the Sun at a speed of roughly 30,000 m/s (67,000 mph). But you need to travel at an even higher speed to overcome the Sun’s gravity and reach the more distant orbit of the red planet. The Spirit rover got the needed boost from the launch rocket, from booster rockets that fired shortly after launch, and from much smaller engines on the spacecraft itself. Read the text aloud Show Action and reaction
How long does it take to reach Mars? The answer is that it depends on the exact alignment between Mars and the Earth at the time of launch. Typical travel times are between 130 and 300 days, where the longer travel times are for heavier payloads. That’s a long trip, and it’s only one way! Read the text aloud
If the rocket reached a velocity of 8,000 m/s after 10 min, what was its average acceleration? Show
Using the average acceleration you just derived, what was the total distance traveled during those 10 min? Show

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