THERE'S CONGLOMERATE ON MARS, GUYS.
the newest update from Curiosity, they've gotten the first photographic evidence of an ancient streambed with actual rounded gravel cemented together as solid rock over time. This cemented-together gravel is known as conglomerate, and is a type of sedimentary rock that forms from river deposits.
These stones were rounded via liquid water at some time in the past, and were left behind when the river dried up. Only a quickly traveling liquid could round these stones in this way and leave them deposited in streaks like those Curiosity has discovered. Previous study from earlier rovers (Spirit and Opportunity) proved that the most common liquid on Mars in its history would've been H20, because of the mineral deposits found in the dirt on Mars. Therefore, it's almost certain that the liquid that rounded these stones was from a stream of water.
|All photo credits to NASA|
And not just any stream. Before now we just knew some water was possible some time in Mars' past. Now we know it's not just "some" water. This was a stream at least ankle deep, but possibly even knee deep in sections, and moving at three feet per second. Three feet per second! And it likely stretched on a long, long ways across the crater where Curiosity is hanging out. This was a serious stream. The thick layers of stone also suggest this wasn't a one time deal: this stream existed for a long period of time, with cycles of flooding and drying.
Wow. This is amazing.
It's been less than two months and Curiosity has already found an ancient, fast-moving stream that could easily have hosted some sort of life. However, the question of whether life was possible on Mars (which is Curiosity's most important job) is still up in the air. Curiosity has found signs of significant amounts of water, but there are many other requirements still missing.
Good thing Curiosity is designed to last at least two entire years more. I can't wait to see what she finds next.