FINTRODUCTION or hundreds of miles in any direction Mars is a dead planet But in one place it is alive Nestled beneath a rocky overhang of rust-red dirt are a cluster of climate-controlled domes A colony of people live inside Some came from Earth but others were born here Unlike their parents the youngest colonists have never seen a plant that wasn’t growing indoors They gaze in wonder at photos of oceans of water They’re surprised to learn that Earth’s moon crosses the sky only once a day Someday their parents promise they will take a vacation to Earth But for now they will have to strap on their oxygen packs and pressurized suits to go outside Life on Mars isn’t easy but it’s home The truth is sending humans to Mars even on a visiting basis is a few decades in the future The trip itself would take months using today’s modes of transportation and space travel is hard on the human body Once they get there Mars’s first visitors will probably stay for several months However Mars doesn’t have anything that’s ready to use Humans can’t breathe its air There’s no food It’s too cold Scientists must develop machines that will let astronauts use Mars’s resources to produce air water and fuel for their vehicles They’ll need to make sure that building materials will hold up in frigid temperatures and in different atmospheric conditions Even with all the essentials surviving in an alien environment will be both physically and mentally challenging Humans have walked on the moon but to go farther will require more creativity better technology and a lot of hard work 4
Mars likely the next space stop for human visitors has been studied from afar photo taken by the Hubble Space Telescope left and up-close a Mars rover above
pace is only an eight-and-a-half-minute trip from Earth on board a space shuttle but it took humans about 100,000 years to figure out how to get there A lot of time and preparation went into discovering how to cross the Kármán Line that point 62 miles 100 km above Earth that scientists identify as the start of space Thousands of years ago humans looked into the skies and wondered about the dots of light they saw What were they How far away were they Why did some move Many early Western astronomers believed that the sun and other planets revolved around Earth but in 1543 Polish scientist Nicolaus Copernicus proposed a different idea He argued that the sun was the center of this solar system Earth he said wasn’t so special after all His theory which angered many people of the time but turned out to be correct kicked off the modern age of astronomy In 1608 a Dutch lens maker created the telescope bringing the stars and planets closer and into sharper focus The telescope was the technology to have in the 17th century Italian scientist Galileo Galilei used one to identify four of Jupiter’s moons In 1609 the instrument helped Johannes Kepler a German astronomer develop a theory on how the planets moved Over the next few centuries more stars planets and moons were discovered By the 20th century some scientists began to talk about actually visiting one of these heavenly bodies But first there was World War II 1939 45 to fight S C H A P T E R O N E C HAPTER O N E 1 FROM THE GROUND UP 6
Galileo Galilei’s contributions to astronomy were vast and included improvements to the telescope the discovery of Jupiter’s moons and observations of spots on the sun
