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New findings point to an Earth-like environment on ancient Mars

discover.lanl.gov

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Re: New findings point to an Earth-like environment on ancient Mars

#101

Post by pjmlp »

jovial_cavalier wrote: post #85
adastra22 wrote: post #27

Earlier quoted context omitted.

You jest, but I seriously believe we are likely martians. Early panspermia from Mars settles a LOT of astrobiological questions about origin of life and LUCA complexity. To be clear, Mars’ descent into inhospitality was totally natural and the result of a smaller planet with stripped atmosphere just outside the habitable zone as the Sun cooled. I doubt Martian life developed to be multicellular. But I bet when we go…

What is your actual mechanism for life getting to Earth from Mars?

I guess we can somehow bind an asteroid, alongside a spaceship crashing in.

Re: New findings point to an Earth-like environment on ancient Mars

#102

Post by somenameforme »

xattt wrote: post #63
adastra22 wrote: post #37

Earlier quoted context omitted.

Mars had 3/4 billion more years to develop, compared with the Earth. Mars formed first, and cooled first due to its smaller size. One of the outstanding problems in astrobiology I mention is that the Earth was inhospitable until 3.8Gya, and the oldest fossils of presumably DNA based life (since it matches existing life we can study) was 3.7Gya. Mars was hospitable ~4.5Gya. So either life emerged IMMEDIATELY on Earth…

At this point, given how much Mars had been roved, why hasn’t some fossil record been discovered yet? At the very least, I would expect something akin to chalk left behind by proto-diatoms that had calcium carbonate skeletons.

Other posts answered, but only if you already know the answer. The rovers we've used on Mars have done an extremely superficial job of scouring the planet. The most recent rover Perseverance has, to my knowledge, the most capable drill with a max depth of 2.4 inches. [1] And the drill is used extremely sparingly because it tends to break quickly, as it did on Curiosity. And of course it can only drill, not excavate/cleave. The first humans on Mars will likely provide more information in a week than decades of probes and rovers have.

[1] - https://attheu.utah.edu/facultystaff/qa-perseverance-rovers-...

Re: New findings point to an Earth-like environment on ancient Mars

#103

Post by meindnoch »

neverokay wrote: post #20
Symmetry wrote: post #17

Earlier quoted context omitted.

For half the history of life on Earth there were no multicellular animals at all[1]. Given how quickly life on Earth arrived I wouldn't be surprised if there were bacteria on Mars. But given how long it took Earth life to develop Eukaryotic cells I'd be surprised if Mars ever developed something as sophisticated as an amoeba. Still, Bacteria do leave fossils like stromatolites and some scientists even think some Mars…

That’s the part that still boggles my mind. How could there not be some kinda micro bacteria on all these planets.

https://en.m.wikipedia.org/wiki/Nanobacterium

Re: New findings point to an Earth-like environment on ancient Mars

#105

Post by ethbr1 »

adastra22 wrote: post #76
ethbr1 wrote: post #64

Earlier quoted context omitted.

If there were extra-terrestrial intervention, it would only have needed to be a one-time event. And it wouldn't be technologically hard to do it such that no trace remains over those timescales. So, yes, that's "crazy". On the other hand, it's unfalsifiable in the absence of other theories.

There are much saner theories for panspermia.

I'm not arguing against that.

I'm just saying unfalsifiability is a bitch, and it's hard to find hard evidence on geologic timescales.

Re: New findings point to an Earth-like environment on ancient Mars

#106

Post by Filligree »

prox wrote: post #60
tokai wrote: post #11

Earlier quoted context omitted.

I don't remember where I read it, but somebody wrote that a geologist with a hammer could do more science in an afternoon than all our mars probes have done combined. Its hard to do science with a rc car, even if said car is cutting edge.

What if we send a humanoid drone next?

Give it a sufficiently advanced AI, and that might work.

Re: New findings point to an Earth-like environment on ancient Mars

#107

Post by wvbdmp »

walterbell wrote: post #65

Kurd Lasswitz wrote "Two Planets" in 1897, https://news.ycombinator.com/item?id=39598983 > Lasswitz's Martians differ little from man physically, but ethically, intellectually, scientifically, and socially they are the prototype of the ideal human being. They seek to educate man, asking in return only air and energy to supplement the diminished supplies in their own, older world. The story revolves around a group of…

Wernher von Braun himself also wrote probably the first serious treatise on human missions to mars as well as a science fiction novel on the topic in 1948. Apparently the original German novel remains unpublished, but there is an English translation available. It’s set in 1980.

https://en.wikipedia.org/wiki/The_Mars_Project

https://en.wikipedia.org/wiki/Project_Mars:_A_Technical_Tale

Check out the second link’s section about “the Elon”.

Re: New findings point to an Earth-like environment on ancient Mars

#108

Post by adastra22 »

Tuna-Fish wrote: post #90
adastra22 wrote: post #27

Earlier quoted context omitted.

You jest, but I seriously believe we are likely martians. Early panspermia from Mars settles a LOT of astrobiological questions about origin of life and LUCA complexity. To be clear, Mars’ descent into inhospitality was totally natural and the result of a smaller planet with stripped atmosphere just outside the habitable zone as the Sun cooled. I doubt Martian life developed to be multicellular. But I bet when we go…

> as the Sun cooled Huh? The Sun has consistently gotten hotter with age.

Thank you for the factual correction. It’s the geothermal (aerothermal?) heat that has decreased by more than the sun’s increasing luminosity, resulting in net temperature loss.

Re: New findings point to an Earth-like environment on ancient Mars

#109

Post by somenameforme »

jovial_cavalier wrote: post #85
adastra22 wrote: post #27

Earlier quoted context omitted.

You jest, but I seriously believe we are likely martians. Early panspermia from Mars settles a LOT of astrobiological questions about origin of life and LUCA complexity. To be clear, Mars’ descent into inhospitality was totally natural and the result of a smaller planet with stripped atmosphere just outside the habitable zone as the Sun cooled. I doubt Martian life developed to be multicellular. But I bet when we go…

What is your actual mechanism for life getting to Earth from Mars?

We already know the meteorites from Mars probably do make their way to Earth on occasion. [1] From there, imagining some primitive life managing to hitch a ride is easy. Even quite advanced life, like tardigrades, have demonstrably survived days of exposure to outer space, and successfully procreated afterwards. [2]

[1] - https://www.space.com/mars-meteorites-on-earth-mystery

[2] - https://en.wikipedia.org/wiki/Tardigrade#Survival_after_expo...

Re: New findings point to an Earth-like environment on ancient Mars

#110

Post by [deleted] »

adastra22 wrote: post #27
pjmlp wrote: post #9

Maybe we are about to discover that we came to Earth after messing up Mars.

You jest, but I seriously believe we are likely martians. Early panspermia from Mars settles a LOT of astrobiological questions about origin of life and LUCA complexity. To be clear, Mars’ descent into inhospitality was totally natural and the result of a smaller planet with stripped atmosphere just outside the habitable zone as the Sun cooled. I doubt Martian life developed to be multicellular. But I bet when we go…

[deleted]
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