[Tyler]

Addressing the possibility of life on Mars
31 October 2018, 7:50 pm

In 2018, millions of people around the world caught glimpses of the planet Mars, discernible as a bright red dot in the summer’s night skies. Every 26 months or so, the red planet reaches a point in its elliptical orbit closest to Earth, setting the stage for exceptional visibility. This proximity also serves as an excellent opportunity for launching exploratory Mars missions, the next of which will occur in 2020 when a global suite of rovers will take off from Earth.

The red planet was hiding behind the overcast, drizzling Boston sky on Oct. 11, when Mars expert John Grotzinger gave audiences a different perspective, taking them through an exploration of Mars' geologic history. Grotzinger, the Fletcher Jones Professor of Geology at the Caltech and a former professor in the MIT Department of Earth, Atmospheric and Planetary Sciences (EAPS), also used the eighth annual John Carlson Lecture to talk to the audience gathered at the New England Aquarium about the ongoing search for life on Mars.

Specializing in sedimentology and geobiology, Grotzinger has made significant contributions to understanding the early environmental history of the Earth and Mars and their habitability. In addition to involvement with the Mars Exploration Rover (MER) mission and the High Resolution Science Experiment (HiRISE) onboard the Mars Reconnaissance Orbiter (MRO), Grotzinger served as project scientist of the Mars Science Laboratory mission, which operates the Curiosity roving laboratory. Curiosity explores the rocks, soils, and air of the Gale Crater to find out whether Mars ever hosted an environment that was habitable for microbial life during its nearly 4.6-billion-year history.

“What I’d like to do is give you a very broad perspective of how we as scientists go about exploring a planet like Mars, with the rather audacious hypothesis that there could have been once life there,” he told the audience. “This is a classic mission of exploration where a team of scientists heads out into the unknown.”

“Simple one-celled microorganisms we know have existed on Earth for the last three-and-a-half billion years — a long time. They originated, they adapted, they evolved, and they didn’t change very much until you had the emergence of animals just 500 million years ago,” Grotzinger said. “For basically 3 billion years, the planet was pretty much alone with microbes. So, the question is: Could Mars have done something similar?”

Part of the research concerning whether or not Mars ever hosted ancient life involves identifying the environmental characteristics necessary for the survival of living organisms, including liquid water. Currently, the thin atmosphere around Mars prevents the accumulation of a standing body of water, but that may not always have been the case. Topographic features documented by orbiters and landers suggest the presence of ancient river channels, deltas and possibly even an ocean on Mars, “just like we see on Earth,” Grotzinger said. “This tells us that, at least, for some brief period of time if you want to be conservative, or maybe a long period of time, water was there [and] the atmosphere was denser. This is a good thing for life.”

To describe how scientists search for evidence of past habitability on Mars, Grotzinger told the story of stratigraphy — a discipline within geology that focuses on the sequential deposition and layering of sediments and igneous rocks. The changes that occur layer-to-layer indicate shifts in the environmental conditions under which different layers were deposited. In that manner, interpreting stratigraphic records is simple, he said.

“It’s like reading a book. You start at the bottom and you get to the first chapter, and you get to the top and you get to the last chapter,” Grotzinger said. “Sedimentary rocks are records of environmental change … what we want to do is explore this record on Mars.”

While Grotzinger and Curiosity both continue their explorations of Mars, scientists from around the world are working on pinpointing new landing sites for future Mars rovers which will expand the search for ancient life. This past summer, the SAM (Sample Analysis on Mars) instrument aboard the Curiosity rover detected evidence of complex organic matter in Gale Crater, a discovery which further supports the notion that Mars may have been habitable once.

“We know that Earth teems with life and we have enough of a fossil record to know that it’s been that way since we get to the oldest, well-preserved rocks on Earth. But yet, when you go to those rocks, you almost never find evidence of life,” Grotzinger said, leaving space for hope. “And that’s because, in the conversion of the sedimentary environment to the rock, there are enough mineralogic processes that are going on that the record of life gets erased. And so, I think we’re going to have to try over and over again.”

Following the lecture, members and friends of EAPS attended a reception in the main aquarium that featured some of the research currently taking place in the department. Posters and demonstrations were arranged around the aquarium’s cylindrical 200,000-gallon tank simulating a Caribbean coral reef, and attendees were able to chat with presenters and admire aquatic life while learning about current EAPS projects.

EAPS graduate student, postdoc, and research scientist presenters included Tyler Mackey, Andrew Cummings, Marjorie Cantine, Athena Eyster, Adam Jost, and Julia Wilcots from the Bergmann group; Kelsey Moore and Lily Momper from the Bosak group; Eric Beaucé, Ekaterina Bolotskaya, and Eva Golos from the Morgan group; Jonathan Lauderdale and Deepa Rao from the Follows group; Sam Levang from the Flierl group; Joanna Millstein and Kasturi Shah from the Minchew group; and Ainara Sistiaga, Jorsua Herrera, and Angel Mojarro from the Summons group.

The John H. Carlson Lecture series communicates exciting new results in climate science to general audiences. Free of charge and open to the general public, the annual lecture is made possible by a generous gift from MIT alumnus John H. Carlson to the Lorenz Center in the Department of Earth, Atmospheric and Planetary Sciences.

Anyone interested in join the invitation list for next year’s Carlson Lecture is encouraged to contact Angela Ellis.

Source: MIT News - CSAIL - Robotics - Computer Science and Artificial Intelligence Laboratory (CSAIL) - Robots - Artificial intelligence

Reprinted with permission of MIT News : MIT News homepage



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[Korrelan]

Just musing… but no one seems to explore or attempt to access other realities if they do indeed exist; we seem content to just explore what we see/ know… why?

AGI’s won’t settle for this, we need to take the spice… we need to start folding space.

Our own mental architecture limits our senses/ understanding. Just because our brains create this nice, cosy 4D sphere for our reality, doesn't mean that’s the only or ‘actual’ reality… dimensions/ time are relative to your reality.

We are… as is our reality 99.9999999% empty space, our reality is governed by rules, just because they are our rules doesn’t mean they are the only rules.
 
And before anyone says anything, I understand that empty space is theoretically impossible under the laws of quantum theory… which only goes to emphasize my point.

There are > trillions of planets and moons out there just in our reality… the notion we are alone is inconceivable to me… I understand the odds… we've just got to find them… or more precisely find ways to perceive them.

We humans need to start thinking outside the… our box.

 

ED: We are the Bathtubians… an intelligent species who live in the water of a bath tub, the limits of the tub is our whole reality… no Bathtubian has ever seen outside the tub.  One day someone notices their reality being sucked/ vanishing down a hole/ point in reality (plug hole).  How can this be? Where is our space reality going? It must be compressing, collapsing under its own gravity… I shall call this a singularity.

Ignorance is not bliss… and no excuse… we need to explore outside the tub.

 

[HS]

The trouble is I've got no concept of what direction outside the box is. If open my eyes I'm just inspecting my brain. Maybe it's more like one big spectrum instead of borders between realities. You can gain access to more of the spectrum by increasing the complexity of your receptor (brain) or by translating foreign signals in to a receivable format (infrared camera).

[infurl]

I think it's safe to assume that at any given time, someone, somewhere, is thinking about something that is outside all the boxes that exist at that time. Most of those thoughts will never get far enough to emerge into the light of civilisation, and some of them that might have will temporarily wither and die because of chance and circumstance. But eventually, I believe that every viable idea will become part of our gestalt and lead on to other things (i.e. new boxes). It's easy to underestimate the power of meatware but computation didn't start with digital computers and while certain things are possible with them now that weren't before, it will be a long time before the fruits of billions of years of evolution are surpassed.

Putting things another way, there are already countless mathematicians, physicists, cosmologists and data scientists routinely thinking in dozens of dimensions at once. For example, the standard model of physics has only the four dimensions that you mention, but string theory requires a minimum of ten dimensions to make it work and there are plenty of people thinking about that already.

[Korrelan]

I totally agree, there are loads of really insightful theorists out there… but no one is actually strapping C4 to the side of the tub… just to see what happens… sometimes a leap is required.

it will be a long time before the fruits of billions of years of evolution are surpassed.

We can fly now...

 

Ed: BTW gestalt... sweet word... I had to look it up.

 

[infurl]

I totally agree, there are loads of really insightful theorists out there… but no one is actually strapping C4 to the side of the tub… just to see what happens… sometimes a leap is required.

There are people leaping all over the place all the time, but for every million leapers, only one lands somewhere interesting. That's the only one that you hear about but it would be wrong to assume that the rest aren't out there.

it will be a long time before the fruits of billions of years of evolution are surpassed.

We can fly now...

Maybe you know this already from your research, or maybe you don't, but bird brains are much more efficient space wise than mammalian brains. That's how they can be so incredibly intelligent with such tiny heads.

https://www.gizmodo.com.au/2016/06/we-finally-know-why-birds-are-so-freakishly-smart/

Cephalopod brains are on a whole other level again.

https://www.theguardian.com/environment/2017/mar/28/alien-intelligence-the-extraordinary-minds-of-octopuses-and-other-cephalopods