NASA made its much-hyped big announcement today, and what it comes down to is that scientists have found the strongest evidence yet that there's liquid water on the Red Planet, the Washington Post reports. Last April, using data from the Curiosity rover, researchers noted that perchlorates were present on the planet. Those are a type of salt, and they could make the boiling point of water on Mars—which is extremely low thanks to low pressure on the planet—much higher, which would mean that liquid water containing perchlorates could form during certain parts of the year. It's been theorized that such water could be responsible for forming the geographic features known as recurring slope lineae (RSL) that have often been seen on Mars. Researchers have been looking at RSL features and found lots of perchlorates that appear to have been getting hydrated.
"We're going to places where we thought we were seeing the presence of water and finding chemical evidence of perchlorates," says the lead researcher. And one of the April researchers, who wasn't involved in this latest study, tells the Post, "[The] flow of liquid salty water is no longer just a possibility; it does actually occur. The results [show] that liquid does indeed flow on Mars today." But more research is necessary to actually confirm liquid water exists on the planet; the lead researcher says he hopes a rover can someday look closely at the RSL features. If liquid water does exist on Mars, it's good news for astronauts who might one day travel there. "If we ever go there, we could probably utilize this. We wouldn't have to bring tons of water," says the lead researcher. "This stuff seems like science fiction, but in 100 years or so it could be fact." It could also "boost the notion of life on Mars," the AP notes.