This is perhaps the biggest news in 2015, and possibly this decade. Scientist have now found direct evidence of liquid water - the best indicator of life - on our neighboring planet Mars. Here are the basic facts of this stunning discovery (via the Guardian):
Liquid water runs down canyons and crater walls over the summer months onMars, according to researchers who say the discovery raises the odds of the planet being home to some form of life.
The trickles leave long, dark stains on the Martian terrain that can reach hundreds of metres downhill in the warmer months, before they dry up in the autumn as surface temperatures drop.
Images taken from the Mars orbit show cliffs, and the steep walls of valleys and craters, streaked with summertime flows that in the most active spots combine to form intricate fan-like patterns.
Nasa confirm discovery of summer watery flows on planet’s surface down cliffs and crater walls that raise odds of finding life on red planet.
Scientists are unsure where the water comes from, but it may rise up from underground ice or salty aquifers, or condense out of the thin Martian atmosphere.
And more details on the study from the Huffington Post:
The study, published online by Nature Geoscience, focuses on the mysterious recurring slope lineae, or "RSL" -- narrow, streaky features on the planet's surface spotted by NASA’s Mars Reconnaissance Orbiter spacecraft.
The RSL are typically about 15 feet in width or smaller, and appear on slopes during the planet's warm seasons. They fade during cooler seasons, then reappear the following year as the planet gets warmer again.
This story is developing.