1. Astronomers detected a planet orbiting Proxima Centauri, the star closest to our sun, that is 1.3 times the mass of Earth and sits within the star's habitable zone.
2. Scientists from LIGO detected gravitational waves from the collision of two black holes over a billion years ago, confirming Einstein's theory of relativity.
3. Archaeological discoveries in Australia have shown that humans have inhabited the continent's interior for at least 49,000 years, 10,000 years longer than previously thought.