Floods of unimaginable magnitude once swept by Gale crater on the equator of Mars



[ad_1]

Gale Crater, Mars - Oblique view

Oblique view of Gale crater, Mars, with vertical exaggeration. The image combines elevation data from the high-resolution stereo camera on the European Space Agency’s Mars Express orbiter, image data from the pop-up camera on the NASA’s Mars reconnaissance orbiter, and information color from Viking Orbiter images. Credit: NASA / JPL-Caltech / ESA / DLR / FU Berlin / MSSS

Field geology at the equator of Mars points to the former mega-flood

Floods of unimaginable magnitude swept through Gale crater Marchequator about 4 billion years ago – a find that hints at the possibility that life may have existed there, according to data collected by NASAThe Curiosity rover and analyzed as part of a joint project by scientists at Jackson State University, Cornell, the Jet Propulsion Laboratory and the University of Hawaii.

The research, “Giant Flood Deposits in Gale Crater and their Implications for Early March Climate,” was published on November 5, 2020 in Nature Scientific reports.

The raging mega-flood – likely triggered by heat from a meteorite impact, which released stored ice on the Martian surface – created gigantic ripples that are telltale geological structures familiar to scientists on Earth.

“We identified mega-floods for the first time using detailed sedimentological data observed by the Curiosity rover,” said co-author Alberto G. Fairén, visiting astrobiologist at the College of Arts and Sciences. “The deposits left by the mega-floods had not been previously identified with the data from the orbiter.

As is the case on Earth, geological features, including the work of water and wind, have been frozen in time on Mars for about 4 billion years. These characteristics convey processes that have shaped the surface of both planets in the past.

Climb Sharp inside Gale Crater on Mars

This false-color composite image of Mount Sharp inside Gale Crater on Mars shows geologists an evolving planetary environment. On Mars, the sky is not blue, but the image was made to resemble Earth so that scientists can distinguish the layers of stratification. Credit: NASA / JPL

This case includes the appearance of giant wave-shaped features in the sedimentary layers of Gale Crater, often referred to as “mega-pearls” or antidunes about 9 meters high and spaced about 450 meters apart, according to lead author Ezat Heydari. , physics teacher. at Jackson State University.

Antidunes point to mega-floods that sank to the bottom of Mars’ Gale crater about 4 billion years ago, which are identical to the features formed by the melting ice on Earth about 2 million years ago, Heydari said.

The most likely cause of the flooding on Mars was the melting ice caused by heat generated by a large impact, which released carbon dioxide and methane from the planet’s frozen reservoirs. The water vapor and the release of gas combined to produce a short period of hot and humid conditions on the Red Planet.

The condensation formed clouds of water vapor, which in turn created torrential, eventually planetary rains. This water entered Gale Crater and then combined with the water coming down from Mount Sharp (in Gale Crater) to produce gigantic flash floods that deposited the gravel ridges in the Hummocky Plains unit and ridges and valleys band formations in the striated unit.

The science team on the Curiosity rover has already established that Gale Crater once had persistent lakes and streams in the past. These long-lived bodies of water are good indicators that the crater, as well as Mount Sharp within, was able to support microbial life.

“The start of Mars was an extremely geologically active planet,” Fairén said. “The planet had the necessary conditions to support the presence of liquid water on the surface – and on Earth, where there is water, there is life.

“So early on, Mars was a habitable planet,” he says. “Was it inhabited? That’s a question the next Perseverance rover… will help answer. “

Perseverance, which launched from Cape Canaveral on July 30, is expected to reach March on February 18, 2021.

Reference: “Giant Flood Deposits in Gale Crater and Their Implications for Early March Climate” by E. Heydari, JF Schroeder, FJ Calef, J. Van Beek, SK Rowland, TJ Parker and AG Fairén, 5 November 2020, Scientific reports.
DOI: 10.1038 / s41598-020-75665-7

Joining Fairén and Heydari on paper are Jeffrey F. Schroeder, Fred J. Calef, Jason Van Beek and Timothy J. Parker, from NASA’s Jet Propulsion Laboratory; and Scott K. Rowland, University of Hawaii.

Data and funding were provided by NASA, Malin Space Science Systems, the Jet Propulsion Laboratory, and the European Research Council.



[ad_2]

Source link