There may be billions of Earth-like planets out there that are abundant with all the elements for life, but that doesn’t mean that there is life, let alone complex life on any of them. The only way to answer the question, “are we alone?” is to go see for ourselves, and this is exactly what NASA has now been empowered to do.

Of course, NASA has had spectacular successes since the Apollo era, building huge machines like the Shuttle and International Space Station, landing audacious vehicles on Mars, and visiting every planet in our solar system with robotic probes. But there has long been a yearning for NASA to rediscover the sense of purpose it had in the Apollo era, a unified goal that can reconnect the divisions of the agency and point them towards a grand and inspiring goal. The agency now has a chance to reconnect its divisions at an extraordinary time in the Space Agency’s history.

NASA has been putting in place all the necessary building blocks to make the Search for Life possible. NASA’s James Webb Space Telescope (JWST), due to launch in late 2018, will begin following up on recently discovered exoplanets, searching for “the fingerprints of life,” gases that scientists believe can only exist in the presence of living organisms. And NASA and private industry have embarked on ambitious new rockets capable of carrying probes and landers to Europa, and launching future telescopes capable of finding and characterizing continents and oceans on Earth-like planets. Soon, they will be able to send (human) geologists and biologists to Mars.

Imagine a world in 2040, where NASA and its partners in industry and academia across the world have been unified, and perhaps rewarded by this search. Imagine that the Europa orbiter and subsequent lander survived the harsh conditions on Europa, only to discover that the cracks in the ice-mantle show evidence of organic life. Imagine the first Martian geologists find fossils of early organisms reminiscent of a pre-eukaryotic Earth. In addition to these results, imagine that the larger successor to JWST a few years earlier has found, in the reflected light of its own sun, a wet, rocky Earth 2.0, where biology is at work. Our world-view will have been irreversibly changed by these discoveries and we will be motivated to find a way to bridge the great distances and go to this new world. This is not outside the realm of possibility. By 2040, it’s possible that we will have designed a fusion rocket engine capable of accelerating a probe to a significant percentage of the speed of light.

What will we find when we get there? Even small variations could create different evolutionary paths. Perhaps we will find a planet very much like Earth, but one on which dinosaurs still roam because no killer asteroid has wiped them out. Or we may find the ruins of an advanced civilization, which would confront us with the deeply troubling possibility that civilizations that have evolved before us have destroyed themselves once they came to dominate their home planet.

What’s next? This is an important question, one that speaks not only to us humans as explorers, but ultimately to our long-term survival. Thanks to NASA’s pivot to include the search for life, young people who are living today may get the chance to answer it.

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