Biggest Scientific Breakthroughs of 2013SEXPAND
From intergalactic neutrinos and invisible brains, to the creation of miniature human "organoids," 2013 was an remarkable year for scientific discovery. Here are 17 of the biggest scientific breakthroughs, innovations and advances of 2013.

Voyager I Leaves the Solar System

Biggest Scientific Breakthroughs of 2013SEXPAND
Escaping the solar system is no mean feat. For 36 years, NASA's Voyager 1 spacecraft has putting distance between itself and the Sun at speeds approaching 11 miles per second. At a pace like that, scientists knew Voyager was approaching the fringes of the heliosphere that surrounds and defines our solar neighborhood – but when would it break that barrier? When would it make the leap to interstellar space? After months of uncertaintyNASA finally made the news official this September. "Voyager 1 is the first human-made object to make it into interstellar space," said Don Gurnett, lead author of the paper announcing Voyager's departure; "we're actually out there."

The CRISPR Craze Takes Off

Biggest Scientific Breakthroughs of 20131SEXPAND
Bacteria have their own version of an adaptive immune system; but "CRISPR," as the system is known, does not target protein antigens they way your immune system does. Instead, CRISPR works by targeting and eliminating specific DNA sequences with matching strands of RNA. What's more, the system is easily manipulated – since researchers first reported harnessing the system in January,writes Elizabeth Pennisi in a perspective piece for Science"various groups have used it to delete, add, activate or suppress targeted genes in human cells, mice, rats, zebrafish, bacteria, fruit flies, yeast, nematodes and crops, demonstrating broad utility for the technique." For scientists in search of new tools, few qualities are more important than versatility and ease of use. CRISPR has both – and, some say, the potential to revolutionize the field of molecular biology.

The Milky Way is Brimming with Habitable Worlds

Biggest Scientific Breakthroughs of 2013SEXPAND
Planet-hunting scientists announced in November that 22% of sunlike stars in the Milky Way are orbited by potentially habitable, Earth-size worlds. This remarkable finding suggests there could be as many as two-billion planets in our galaxy suitable for life — and that the nearest such planet may be only 12 light-years away. Is Earth 2.0 out there? With figures like that, it's hard to imagine otherwise. Who knows – with all the Kepler data we've got to sift through, there's a chance we've already found it. [Image Credit M. Kornmesser/ESO]

Brain-to-Brain Interfaces Have Arrived