Why Haven't We Colonized Mars Yet?

Charles Q. Choi, SPACE.com Contributor

Humanity has been flying in space for 50 years now, but we are still confined to a single planet — Earth.

If it took only eight years to go from no humans in space to the first man on the moon, why haven't humans colonized Mars and other worlds yet? Or at the least the moon?

"NASA's plan as of 1969 was to have a human Mars mission by 1981, a permanent moon base in the '80s and a permanent Mars base in 1988," said Robert Zubrin, president and founder of the Mars Society.

Interplanetary human voyages pose definite scientific and technological challenges. One would have to deal with the rigors of travel — issues of food, water and oxygen, the deleterious effects of microgravity, potential hazards such as fire and radiation and the fact that any such astronauts would be millions of miles away from help and confined together for years at a time. Landing, working, living and returning from another planet would offer a host of challenges as well. [Vote! The Best Spaceships of All Time]

Space exploration versus politics

Still, the main reason that people have not yet voyaged past the orbit of the moon is mostly a political one.

The era of human spaceflight began on April 12, 1961, when the Soviet Union shocked the world by launching cosmonaut Yuri Gagarin, the first man in space, into orbit. At the time, the so-called Space Race was under way, with the United States and Soviet Union both working to land a human on the moon first. That race ended with NASA's historic Apollo 11 moon shot, which landed astronauts Neil Armstrong and Buzz Aldrin on the lunar surface on July 20, 1969.

"The Cold War is over," said Bill Nye, executive director of the Planetary Society.

Back in the early days of human spaceflight, the United States and Soviet Union were locked in the Cold War, a life-or-death struggle that spurred the space race for control of the ultimate high ground.

Since then, however, "we've had a major failure of political leadership in this country when it came to human spaceflight," Zubrin said. "It'd be like Columbus coming back from America and Ferdinand and Isabella saying, 'so what?'"

A question of will

Although one "can talk forever about the technical problems, those are red herrings," Zubrin said. "You can talk about the risk of being exposed to radiation in space for years, but cosmonauts have already had larger cosmic ray doses at the International Space Station and Mir. This isn't a question of technical challenges — it's a question of will." [The Best (and Worst) Mars Landings]

"You can say it's risky, but imagine all the risks human spaceflight faced in the beginning," Zubrin said. "When Kennedy gave his speech in May of 1961 about putting a man on the moon, we had 15 minutes of human spaceflight experience, and yet we went."

"My uncle landed on Normandy beach," Zubrin said. "They didn't hold up the Normandy landing until they knew it was safe. If you're going to wait to go to Mars until it's going to be safe, you're never going to Mars."

The goal now "is toget people to realize the value of human spaceflight," Nye said. "When we explore with robots, we make discoveries, but not nearly as fast as with people, and not in the same engaging way."

"This is really a challenge of who we are, what kind of people we are," Zubrin said. "Are we willing to accept challenges and embrace risk? Or are we ultimately resigning from our role as a nation of pioneers?"

Follow SPACE.com contributor Charles Q. Choi on Twitter @cqchoi. Visit SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

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6 Surprising Facts About the First Human Spaceflight

Space.com  

Fifty years ago on April 12, 1961, Russian cosmonaut Yuri Gagarin became the first person in space, ushering in the era of human spaceflight.

The rocket carrying Gagarin's Vostok 1 spacecraft blasted off from Baikonur Cosmodrome at 6:07 a.m. local time at the Soviet Union launch site. [Photos: Yuri Gagarin, First Man in Space]

Reaching unprecedented speeds for human travel at the time, the spacecraft broke free of the Earth's gravitational pull and entered orbit around the planet, circling once before re-entering the atmosphere and landing back on Soviet soil.

Here are six facts about Gagarin's historic mission:

How long was Gagarin up there?

The total mission lasted just 108 minutes, and the trip once around the Earth at 17,500 mph (most of the way) took less than an hour and a half. [Video: The First Human Spaceflight]

In that time, Vostok 1 completed one not-quite-circular orbit, at a maximum altitude of 203 miles, before slowing down to the point that the capsule was pulled back into the atmosphere for ballistic re-entry.

What kind of vessel was the Vostok 1?

The Vostok was a spherical capsule, designed to eliminate changes in center of gravity. In that way, the craft could assure comfort for its one-man crew no matter its orientation. What it wasn't designed to do was land with a human still on board.

Unlike later Russian space vehicles, such as the modern Soyuz capsule, Vostok 1 was not outfitted with thrusters to help slow it down as it headed back toward Earth, so Gagarin had to eject before reaching ground, at an altitude of around 4 miles.

But since the achievement would not have been regarded as the first successful manned mission to space unless it included a manned landing, the Russians kept this little detail out of official press releases. [How the First Human Spaceflight Worked]

What prevented earlier missions from reaching orbit?

In a word: speed.

In order to escape Earth's gravitational pull, a ship needs to hit 17,500 mph, or about 5 miles per second. Before the Vostok 1 mission, no rocket was powerful enough to get a vessel going that fast. The Vostok capsule's cannonball shape helped the rocket and spacecraft reach the necessary velocity.

How did they test the Vostok before Gagarin’s mission?

A few weeks prior, a prototype of Gagarin's craft, the Vostok 3KA-2, completed one low-Earth orbit carrying a life-size dummy named Ivan Ivanovich and a dog called Zvezdochk.

Ivan was sold in a Sotheby's auction in 1993.

Who was Yuri Gagarin?

Yuri Gagarin was a 27-year-old Soviet Air Force pilot when he made his first and only trip into space. Upon his triumphant return he instantly became a national treasure, too valuable to send on such a dangerous mission again.

It's a sad irony, then, that when Gagarin was finally scheduled to ascend to the cosmos once more, he died in a crash during a routine training exercise. Gagarin remained a hero after the fall of the Soviet Union; statues of him were preserved while monuments to Russia's Communist leaders were torn down.

Modern cosmonauts still observe a sacred launch-day tradition based on Gagarin's preflight preparations in 1961. On the way to the launch pad, the bus carrying the crew stops so that the members can hop out and "take a leak," just as Gagarin did the morning he made history.

Launch pad still in use

One lasting legacy of Gagarin's historic spaceflight is the mission's launch pad at Baikonur Cosmodrome. The launch pad is still in use today – with the latest crew of the International Space Station blasting off from the site last week on April 5 local time (late April 4 EDT).

Baikonur Cosmodrome is one of several launching sites used by Russia's Federal Space Agency (also known as Roscosmos), but it is not in Russia. The launch site is in Kazakhstan, a country that was part of the Soviet Union during the Cold War but is now a separate nation.

Cosmonauts continued launching from Gagarin's Vostok 1 pad throughout the Cold War, and the tradition continues to this day.

This article was provided by Life's Little Mysteries, a sister site to SPACE.com.

Video: The First Human Spaceflight 

Photos: Yuri Gagarin, First Man in Space 

Giant Leaps: Top Milestones of Human Spaceflight 

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