Many scientists believe the origins of life on Earth lie in comets that smashed into the planet, bringing with them the building blocks of life. So humankind may have sprung from comets.

And now we've landed on one.

Philae, the lander that's been traveling on the Rosetta spacecraft since 2004, touched down Wednesday on a comet that is named 67P/Churyumov-Gerasimenko for the two scientists who discovered it. Landing a rover on a comet zooming through space at 41,000 mph is yet another giant leap for mankind. And not just technologically.

The exploration of space was rooted both in the competitive development of missiles during World War II, and in the Cold War race between the USSR and the United States. When President John F. Kennedy announced in 1961 that we would land a man on the moon and return him safely by the end of the decade, it was largely in response to the belief that the Soviets were ahead of us.

But today, breakthroughs in space exploration are generally collaborative. Rosetta is a project of the European Space Agency, a cooperative of 20 nations. And comet exploration and Rosetta are worldwide missions of cooperation; NASA and the Russian and Japanese space agencies have all played a part. How fitting, then, that Philae is a Greek word for "friend."

Connecting space technology to top-secret weaponry is expected, but ideally, breakthroughs should blaze a path toward peace and shared prosperity. That humans accomplished this feat makes our hearts soar. The knowledge that could come from it makes our heads spin. But it's the fact that nations did it cooperatively that makes our souls sing.