IF A small, scrappy group at NASA鈥檚 Jet Propulsion Laboratory (JPL) in Pasadena, California, get their way, the 100th anniversary of Apollo 11 鈥� the first crewed moon landing 鈥� will see a spacecraft launched to a nearby exoplanet to look for life.
The project is so new it doesn鈥檛 have a name 鈥� and most of the technology it needs doesn鈥檛 exist yet. But there鈥檚 plenty of time to work out the kinks before 2069.
鈥淚t鈥檚 very nebulous,鈥� says Anthony Freeman at JPL, who presented the mission concept at the 2017 American Geophysical Union conference in New Orleans, Louisiana, on 12 December.
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The impetus came from a 2016 US funding bill telling NASA to study interstellar travel that could reach at least 10 per cent of the speed of light by 2069. It also directed the agency to launch a mission to Alpha Centauri, the nearest star system to ours.
The JPL group has drafted science goals for the mission, including studying the make-up of the matter and radiation it encounters, and testing general relativity on the way. Upon arrival, the probe should make observations of the planetary system, plus the atmosphere and landscape of the target exoplanet.
A few years after the launch, NASA would send a large telescope to deep space. There, it would position itself so that light from Alpha Centauri grazes our sun, meaning gravitational lensing can give us a full view of the exoplanet.
The probe鈥檚 primary goal will be to determine whether life is present. After all, the telescope could confirm virtually everything else.
鈥淲e鈥檒l be able to characterise the atmosphere. We鈥檒l be able to see the planet, assuming it鈥檚 not covered in clouds,鈥� says JPL鈥檚 Stacy Weinstein-Weiss, lead author of the paper outlining the concept. Techniques to detect life once in orbit include looking for artificial structures, lights going on and off, and large-scale land modification.
The target might not be Alpha Centauri, depending on who you ask 鈥� the group has identified other sun-like stars close enough to visit. Wherever is chosen, one big hurdle is that no technology we have can get a craft to a decent fraction of the speed of light.
What鈥檚 more, entering orbit upon arrival would add decades to the mission, says Avi Loeb at Harvard University, who is part of the interstellar Breakthrough Starshot initiative. 鈥淭his requires braking and a low travel speed for the spacecraft, much less than a tenth of the speed of light, which implies a trip time of centuries or more,鈥� says Loeb.
The JPL team is exploring ways to power a spaceship travelling at 10 per cent the speed of light 鈥� including antimatter-matter collisions, nuclear propulsion, and even laser-powered light sails like those Breakthrough Starshot will use, which the team says are most promising.
Of course, there鈥檚 no guarantee this spaceship will ever leave the drawing board. But if it does gain steam, it could even give us better ways of getting around our own solar system.
This article appeared in print under the headline 鈥淣ASA dreams of Alpha Centauri trip鈥�
