Credit: NASA/JPL-Caltech

 

NASA’s latest addition to Red Planet probing is the Perseverance robot – now getting up to speed on Mars within Jezero crater. Scientists believe the area was once flooded with water and was home to an ancient river delta.

Credit: NASA/JPL-Caltech/Univ. of Arizona/ESA

However, early imagery relayed from Perseverance has provided some “geo…logical” head-scratching.

Picture-sleuthing science

Credit: NASA/JPL-Caltech/Jack Mustard

Jezero rock photos appear to indicate volcanic activity – and perhaps the Mars machinery is sitting in leftover volcanic rock and dust. Some picture-sleuthing readers have suggested that the water “trail” isn’t there…there is simply not enough erosion.

To help sort out the sorted details, Inside Outer Space asked noted expert Jack Mustard, professor in Brown University’s Department of Earth Environmental and Planetary Sciences, what’s the lowdown on those rocks?

“The first impression could give that interpretation, as they have landed on the Jezero mafic floor unit, which is variably interpreted as volcanic flows, volcanic tephra (ash and particulates) or maybe eolian [pertaining to the activity of wind].

Credit: NASA/JPL-Caltech/Jack Mustard

Too soon to tell

Mustard said Perseverance is actually in a place where the delta may have been long ago but has since eroded away, “so this mix of dust, fragments and rounded pebbles could be what is expected.” It’s too soon to tell, he adds.

In the photos shown here taken by Perseverance and provided by Mustard, these images shore up the interpretation.

Credit: NASA/JPL-Caltech/Jack Mustard

“But the vesicles could be volcanic from degassing of volatiles from a flow,” Mustard says. They could be pits formed from eolian abrasion “or through other weather processes such as seen in pits we see on Ferrar Dolerite rocks in the McMurdo Dry Valleys.”

No doubt, more imagery and use of Perseverance’s tools will help decipher the nature of the Jezero site.

Credit: NASA/JPL-Caltech/Jack Mustard

Eye of the beholder

Meanwhile, there’s a geological axiom worth considering: the “tyranny of shiny objects.”

Planetary geologist Jim Head, also at Brown University says that the meaning is what attracts the attention of the eye may be interesting, “but should be put in the context of ‘obtaining a representative sample’…as you may get a ‘piece of broken glass’ and not basic rocks/soils that actually hold the story of the origin and evolution of the region.”

2 Responses to “Perseverance Mars Rover: Off to a “Rocky” Start?”

  • I thought the NASA Perseverance rover landed in the perfect location where the issue of ancient life on Mars might be finally settled – near a former river delta leading into a fresh water lake not far from an ocean basin that may have existed in Isidis Planitia. When the rover literally touched down on top of the “holey” rocks peppering the landing site I couldn’t believe what I saw. I immediately recognized these kinds of rocks from the 25 years’ worth of observations, study and collecting Ordovician period rocks I found from the shores of Lake Ontario. Having lived most of my life near Lake Ontario I routinely came across sandstone and mudstone rocks with numerous vesicles (holes) in them from a time 485-450 million years ago when much of New York State was submerged under a warm shallow inland sea some 15 degrees south of the equator. I would soon find that the vesicles in these “holey” rocks represented a snapshot of what the ancient sea floor looked like during the Ordovician period at that time when the sea floor was teeming with all sorts of early metazoan (multicellular eukaryotic organisms) marine invertebrates, including calcareous bryozoans, bivalves, graptolites, trilobites, and brachiopods. The ancient sea floor made up of sand eroded from the Teconic mountains which then lithified into rock and entombed any calcareous marine life. Later the ancient sea floor was broken up by a series of glacial events and then was scattered across what would become the North American continent. Between 7,000 to 32,000 years ago glaciers scoured the landscape digging out Great Lake basins that began filling with water when the ice began to melt 14,000 year ago. The Ordovician rocks – remnants of the ancient sea floor, became deposited in the Lake Basins and eventually rounded by beach erosion. As some of the rocks with entombed calcareous fossils became buried in soils along the shores, humic acids in the soil along with acid rainfall percolated through the soil and “ate” away the calcareous fossils leaving only the sandstones with apparent vesicles in them. The fossilized animals were dissolved out.

    During the time I was writing my first book in 1995 Mars The Living Planet I had looked through hundreds of images from both Viking Lander sites and noticed the extreme coverage of vesicles in the Viking 2 Lander rocks. The rocks at the Viking lander 1 site in Chryse Planitia by comparison, had few, if any vesicles. I then remembered some scientific papers that had been written about a possible ocean in the northern hemisphere of Mars – the Borealis Ocean. At that point I became so intrigued by their similarity to the Lake Ontario Ordovician rocks with vesicles in them to those at the Viking Lander 2 site that I presented and published a 2003 paper for the SPIE Astrobiology Conference in San Diego, California – Proc. SPIE 4859, Instruments, Methods, and Missions for Astrobiology V, (26 February 2003); https://doi.org/10.1117/12.457566 .

    I put together some of my Lake Ontario images comparing them to those at the Perseverance Landing site images for a German blog here:

    https://www.grenzwissenschaft-aktuell.de/grewi-exklusiv-neuer-mars-rover-koennte-missionsziel-schon-am-landeort-erfuellen20210307/

    There has been a debate among the Perseverance science team as to the origin of the vesicles they are seeing in the rocks at the landing site and most have centered around a volcanic origin or wind eroded ventifacts. I think an easy way to check to see if the Perseverance rocks are similar to the Ordovician specimens I have studied is to do chemical and minerology analyses with Supercam. If the rocks on Mars with the numerous vesicles in them are volcanic – then they should be composed of basalt. If they show sedimentary layering and composed of sandstone or mudstone like many of the rocks I have studied at Lake Ontario, then it could mean evidence of bioturbation by ancient soft bodied metazoan life forms that lived and moved in wet lake sediments and left trace fossils of their movements behind in the rocks or possible biogenic dissolution cavities.

    Yet I see the rover is already on the move from images just released from Sol 15. Does this mean the science team has decided not to investigate them? If so I must ask why not?

    I am looking forward to the Chinese Tianwen-1 rover landing in Utopia Planitia ( location of the putative ancient Borealis Ocean on Mars) later next month at a site where I began my research into the numerous vesicles in the rocks on Mars at the Viking 2 Lander site over 25 years ago.

    Wouldn’t it be amazing to find out that Perseverance landed right on top of its mission goal – solid evidence for ancient life on Mars which would probably predate similar Earth life by two billion years?

    Sincerely,

    Barry E. DiGregorio

  • Leonard David says:

    I thought the NASA Perseverance rover landed in the perfect location where the issue of ancient life on Mars might be finally settled – near a former river delta leading into a fresh water lake not far from an ocean basin that may have existed in Isidis Planitia. When the rover literally touched down on top of the “holey” rocks peppering the landing site I couldn’t believe what I saw. I immediately recognized these kinds of rocks from the 25 years’ worth of observations, study and collecting Ordovician period rocks I found from the shores of Lake Ontario. Having lived most of my life near Lake Ontario I routinely came across sandstone and mudstone rocks with numerous vesicles (holes) in them from a time 485-450 million years ago when much of New York State was submerged under a warm shallow inland sea some 15 degrees south of the equator. I would soon find that the vesicles in these “holey” rocks represented a snapshot of what the ancient sea floor looked like during the Ordovician period at that time when the sea floor was teeming with all sorts of early metazoan (multicellular eukaryotic organisms) marine invertebrates, including calcareous bryozoans, bivalves, graptolites, trilobites, and brachiopods. The ancient sea floor made up of sand eroded from the Teconic mountains which then lithified into rock and entombed any calcareous marine life. Later the ancient sea floor was broken up by a series of glacial events and then was scattered across what would become the North American continent. Between 7,000 to 32,000 years ago glaciers scoured the landscape digging out Great Lake basins that began filling with water when the ice began to melt 14,000 year ago. The Ordovician rocks – remnants of the ancient sea floor, became deposited in the Lake Basins and eventually rounded by beach erosion. As some of the rocks with entombed calcareous fossils became buried in soils along the shores, humic acids in the soil along with acid rainfall percolated through the soil and “ate” away the calcareous fossils leaving only the sandstones with apparent vesicles in them. The fossilized animals were dissolved out.

    During the time I was writing my first book in 1995 Mars The Living Planet I had looked through hundreds of images from both Viking Lander sites and noticed the extreme coverage of vesicles in the Viking 2 Lander rocks. The rocks at the Viking lander 1 site in Chryse Planitia by comparison, had few, if any vesicles. I then remembered some scientific papers that had been written about a possible ocean in the northern hemisphere of Mars – the Borealis Ocean. At that point I became so intrigued by their similarity to the Lake Ontario Ordovician rocks with vesicles in them to those at the Viking Lander 2 site that I presented and published a 2003 paper for the SPIE Astrobiology Conference in San Diego, California – Proc. SPIE 4859, Instruments, Methods, and Missions for Astrobiology V, (26 February 2003); https://doi.org/10.1117/12.457566 .

    I put together some of my Lake Ontario images comparing them to those at the Perseverance Landing site images for a German blog here:

    https://www.grenzwissenschaft-aktuell.de/grewi-exklusiv-neuer-mars-rover-koennte-missionsziel-schon-am-landeort-erfuellen20210307/

    There has been a debate among the Perseverance science team as to the origin of the vesicles they are seeing in the rocks at the landing site and most have centered around a volcanic origin or wind eroded ventifacts. I think an easy way to check to see if the Perseverance rocks are similar to the Ordovician specimens I have studied is to do chemical and minerology analyses with Supercam If the rocks on Mars with the numerous vesicles in them are volcanic – then they should be composed of basalt. If they show sedimentary layering and composed of sandstone or mudstone like many of the rocks I have studied at Lake Ontario, then it could mean evidence of bioturbation by ancient soft bodied metazoan life forms that lived and moved in wet lake sediments and left trace fossils of their movements behind in the rocks or possible biogenic dissolution cavities.

    Yet I see the rover is already on the move from images just released from Sol 15. Does this mean the science team has decided not to investigate them? If so I must ask why not?

    I am looking forward to the Chinese Tianwen-1 rover landing in Utopia Planitia ( location of the putative ancient Borealis Ocean on Mars) later next month at a site where I began my research into the numerous vesicles in the rocks on Mars at the Viking 2 Lander site over 25 years ago.

    Wouldn’t it be amazing to find out that Perseverance landed right on top of its mission goal – solid evidence for ancient life on Mars which would probably predate similar Earth life by two billion years?

    Sincerely,

    Barry E. DiGregorio

Leave a Reply