Today we learned something new, and amazing, about Mars. But, although today was the day that the news was confirmed, it’s been in the making for quite sometime. Here, in pictures, is a history of how we finally found out that there really was water flowing up on Mars.


Top Image: Recurring slope lineae (RSL) on Garni Crater, 2015 / NASA/JPL-Caltech/Univ. of Arizona


We’ve been looking at new images showing the movement of water on Mars today. Those new images are pretty incredible, but while these latest images are the ones that helped confirm the discovery, the photos that led up to it have been trickling in for almost up to a decade—and those older photos are pretty important too.



Here, we’ve assembled a look back at pictures of water on Mars—from the flyover footage released today, to the before-and-after GIF that the researchers released in their then preliminary study in 2011, to the then-unconfirmed photos of areas that they only thought may contain water from almost over a decade ago.

2015 Photos

Image: A flyover visualization of the gullies from NASA/JPL’s studio, 2015


Image: Streaks formed by the flow of water, 2015 / NASA/JPL/University of Arizona


Image: A still from Lujendra Ojha presentation of the data for NASA today, showing precisely where along the gullies the discovery was made, 2015


Image: RSL at Horowitz Crater on Mars, 2015 / NASA/JPL-Caltech/Univ. of Arizona


Image: A GIF showing what researchers then believed, but weren’t yet sure, was water flowing on Mars, 2011 / NASA/JPL


Image: RSL in Coprates Chasma, which researchers believed (but hadn’t confirmed yet) were the result of water seepage, 2014 / NASA/JPL/University of Arizona


Image: Gullies showing evidence of water carving on Mars, 2007 / NASA/JPL/University of Arizona


Image: Gully channels on Mars, 2007 / NASA/JPL/University of Arizona


Image: Mars gully deposits, 2006 / NASA/JPL/Malin Space Science Systems