As Perseverance sits in the desolate swathe of Jazero crater, the Perseverance rover continues to collect data even as Earth’s communications with Mars cease. The Jezero is a dry, eroded depression where today’s rover is parked, but marks the former location of a well-fed lake, according to a new analysis of images of the region.
It appears that the area had significant flooding events as far back as 3.7 billion years ago, based on images received by the rover before it went dark on the rock. There were rivers flowing when Mars had an atmosphere thick enough to sustain water, and the delta of a fan-shaped river was flooded late in its history.
In a recent article published in the journal Science, an analysis of the hydrological cycle of Jezero Crater is revealed to be more complex and interesting than previously thought. Analysis of the massive boulders suggests they were swept up by flash floods in the area, which carried them miles upstream and deposited them on the lakebed, where they lie today.
Mars suffers flash floods
Researchers discovered that the outcrop once was a river delta based on images taken by the rover’s left and right Mastcam-Z cameras as well as the Remote Micro-Imager. Sediment analysis indicates that the delta fed into a lake that was calm until the last period of the lake was flooded by a major climatic event.
Weiss, a professor of planetary science in the Department of Earth, Atmospheric, and Planetary Sciences at MIT, said in a statement, “These images represent an epic desert landscape.”. It is the loneliest place you could ever dream of visiting. We don’t see a speck of water here, but we can still see signs that we lived in a very different era. “The planet has experienced something very profound.”
In February, Perseverance landed in the Jazero crater on Mars. Engineers have succeeded in scooping samples from the surface, which will be returned to Earth via upcoming missions. It has been more than two years since Perseverance landed.
An early glimpse
The rover landed in the crater in February and stayed stationary while engineers checked its health before revving up its engine to begin exploring. Long-distance photos were then taken of the formation known as Kodiak butte and the edge of the outcrop at this time. It has since partially eroded, but geologists believe that Kodiak may once have been connected to the main fan-shaped outcrop.
Currently, the Red Planet’s Kodiak rover is operated by the Jet Propulsion Laboratory (JPL), which has only seen it from orbit. Mastcam-Z and RMI images obtained by the rover revealed for the first time the stratigraphy, the order and the position of rock layers along Kodiak’s eastern face, which provides information about when geological deposits occurred.
“Never before has such well-preserved stratigraphy been visible on Mars. This is the key observation that enables us to once and for all confirm the presence of a lake and river delta at Jezero. Getting a better understanding of the hydrology months in advance of our arrival at the delta is going to pay big dividends down the road,” Nicolas Mangold, a Perseverance scientist told JPL.
An even deep lake
An outflow river channel is visible on the orbital imagery of the crater’s eastern rim where the ancient lake levels have been high enough. According to the article, the lake’s size fluctuated over time with “its water level rising and falling by tens of yards before the body of water disappeared entirely.”
The reason that the levels kept changing has not yet been explained, it might have been climatic factors or flooding, but geologists determined that it happened later in the Jezero delta’s history, when the lake level was at least 100 meters below its highest point.
“A better understanding of Jezero’s delta is a key to understanding the change in hydrology for the area and it could potentially provide valuable insights into why the entire planet dried out,” said Sanjeev Gupta, a Perseverance scientist from Imperial College, London, and a co-author of the paper.