‘Cradle of life’ on Mars? Scientists discover evidence for hydrothermal deposits in ancient sea

Part of the Eridania basin, where ancient hydrothermal deposits have been surrounded by younger volcanic deposits in what was once a sea. Photo Credit: NASA/JPL-Caltech/MSSS

Does Mars, or did it ever, have life? We still don’t know the answer to that question, but scientists have found new evidence that at least one region had ancient sea-floor hydrothermal activity, a discovery that increases the chances that microbial life may have once existed, and could also provide clues as to how life started on Earth.

The new findings are based on observations by NASA’s Mars Reconnaissance Orbiter (MRO) of a basin in the southern hemisphere called Eridania. The basin contains huge deposits which scientists think were formed by hot water which entered the bottom of a large sea about 3.7 billion years ago. The water was heated by volcanic activity, but today, the volcanoes are no longer active and the sea has long since evaporated.

Eridiani basin in the southern hemisphere of Mars. This basins now thought to have once contained an ancient sea. Image Credit: NASA
Diagram depicting how the hydrothermal deposits in the ancient sea are thought to have originated, as well as water depth estimates. Image Credit: NASA

“Even if we never find evidence that there’s been life on Mars, this site can tell us about the type of environment where life may have begun on Earth,” said Paul Niles of NASA’s Johnson Space Center in Houston. “Volcanic activity combined with standing water provided conditions that were likely similar to conditions that existed on Earth at about the same time – when early life was evolving here.”

This undersea hydrothermal activity would likely have been similar to what still occurs on Earth today, and at about the same time when life is thought to have started here. As such, this sea could have been a “cradle for life” on Mars.

“This site gives us a compelling story for a deep, long-lived sea and a deep-sea hydrothermal environment,” Niles said. “It is evocative of the deep-sea hydrothermal environments on Earth, similar to environments where life might be found on other worlds – life that doesn’t need a nice atmosphere or temperate surface, but just rocks, heat and water.”

Cutaway view depicting the interior of Saturn’s moon Enceladus. Water, salts, organics, and methane make their way from the hydrothermal vents on the ocean bottom to the surface through cracks in the icy crust, erupting as geysers. Image Credit: NASA/JPL
Artist’s conception of what ancient Mars may have looked like with seas and oceans. Image Credit: Ittiz/Wikimedia Commons

There is still much debate as to whether Mars once had a larger ocean in the northern hemisphere, but even a smaller sea could have provided very habitable conditions. This sea is estimated to have contained 210,000 cubic kilometres (50,000 cubic miles) of water, nine times more than all of the Great Lakes on Earth. Minerals found in the deposits by MRO include serpentine, talc and carbonate.

“Ancient, deep-water hydrothermal deposits in Eridania basin represent a new category of astrobiological target on Mars,” according to the report. “Eridania seafloor deposits are not only of interest for Mars exploration, they represent a window into early Earth.”

There is also now evidence for current hydrothermal activity on the bottom of Enceladus’ global subsurface ocean, and perhaps Europa as well, which makes these moons prime targets in the search for life elsewhere in the Solar System.

The new hydrothermal findings add clue to the growing knowledge that Mars was once a very wet place, with rivers, lakes, deltas, seas, groundwater and hot springs.

This article was first published on AmericaSpace.

 

SaveSave

SaveSave

SaveSave

SaveSave

SaveSave


Bright ‘tower’ in Mars orbiter image: Anomaly or natural formation?

The bright object seen by the Mars Reconnaissance Orbiter. Image Credit: NASA/JPL-Caltech/MSSS/Daily Mail

With thousands of images taken by various probes sent to Mars, it would seem inevitable that unusual or puzzling objects might be seen in some of them. And of course, there have been, most notably the famous “Face on Mars” first seen in low-resolution Viking orbiter images in the 1970s. Higher-resolution images taken later by other orbiters with better cameras showed it, and nearby interesting formations, to be just natural hills and mesas. Despite that, other curious things are seen in both orbital and ground images from time to time, although they almost always have a simple prosaic explanation. Another such oddity was just recently seen in an image taken by the Mars Reconnaissance Orbiter (MRO), which has attracted some attention. Most likely it is a natural rock formation, but it’s also not, as described by the tabloid Daily Mail, a “spherule” either.

Read More…

Image Gallery: Conical hill and sand dunes in Ganges Chasma

Photo Credit: NASA/JPL/University of Arizona
Conical hill and sand dunes in Ganges Chasma. Click for larger image. Photo Credit: NASA/JPL/University of Arizona

Another odd but beautiful image of Mars, showing a cone-shaped hill with sand dunes wrapping around it. The formation is in the Ganges Chasma region, and the image was taken by the HiRISE camera on the Mars Reconnaissance Orbiter. Mars has a lot of diverse geology, and this is another good example of that. Original images are here.

Read More…

Ten years at Mars: Mars Reconnaissance Orbiter celebrates a decade of discovery

Illustration of Mars Reconnaissance Orbiter (MRO) as it entered orbit ten years ago. Image Credit: NASA/JPL
Illustration of Mars Reconnaissance Orbiter (MRO) as it entered orbit ten years ago. Image Credit: NASA/JPL

The Martian rover Opportunity has become famous for its amazing longevity, but it is not the only one; orbiting spacecraft also usually enjoy long lifespans, and today the Mars Reconnaissance Orbiter is celebrating its 10th year exploring Mars from above. It has helped to revolutionize our understanding of Mars and its complex geological history as well as, of course, sending back thousands of incredible high-res images of the Martian surface.

Read More…

The saline slopes of Mars: NASA confirms evidence for flowing liquid water

False-colour image of RSL on slopes in Hale crater. The blue colour is thought not to be related to their formation, but instead are from the presence of the mineral pyroxene. The image is produced by draping an orthorectified (Infrared-Red-Blue/Green(IRB)) false colour image (ESP_030570_1440) on a Digital Terrain Model (DTM) of the same site produced by High Resolution Imaging Science Experiment (University of Arizona). Vertical exaggeration is 1.5. Image Credit: NASA/JPL/University of Arizona
False-colour image of RSL on slopes in Hale crater. The blue colour is thought not to be related to their formation, but instead are from the presence of the mineral pyroxene. The image is produced by draping an orthorectified (Infrared-Red-Blue/Green(IRB)) false colour image (ESP_030570_1440) on a Digital Terrain Model (DTM) of the same site produced by High Resolution Imaging Science Experiment (University of Arizona). Vertical exaggeration is 1.5.
Image Credit: NASA/JPL/University of Arizona

In a finding that is sure to fuel the ongoing debate about possible life on Mars, NASA announced yesterday the confirmation that intriguing seasonal dark streaks running down Sun-facing slopes are indeed flows of liquid water. The water is salty (briny), but just the fact that it is current liquid water, albeit transient and in relatively small amounts, is still big news.

Read More…