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

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

#311

Post by HarHarVeryFunny »

lagniappe wrote: post #93
HarHarVeryFunny wrote: post #46

Earlier quoted context omitted.

It seems very low likelihood that a life-bearing chunk of Mars arrived and seeded life here. What are the chances that some type of single-cell critter(s) from Mars were robust enough to: 1) Survive the trip here with the extreme cold of space, AND 2) Survive the searing heat of entering earth's atmosphere, AND 3) Survive conditions on earth, when they were adapted to the martian environment And that's all premised o…

Curious why there is much less interest in the Pleiades, which is made of all of our same material and is very likely a "fork" of earth formed after the original mass that later became earth and moon colliding with another body in early history. https://en.wikipedia.org/wiki/Giant-impact_hypothesis

Perhaps, but given how sterile the moon appears to be, it's not obvious why the Pleidas would be any different, even assuming they were created by the same potentially life-seeding impact.

I can see the purely historical interest in knowing how the earth and moon were formed, where our water came from, where terrestial life originated, etc, but it seems (maybe I'm wrong?) that a large part of the interest in extra-terrestial origin of life consideration is from people who don't want to believe that life is all-but-inevitable in the right conditions and therefore presumably did originate here (and very quickly after earth formed - within a few 100M years). However, if creation of life is an extremely rare event, then the likelihood of it having spread from such a rare source to any other compatible planet seems vanishingly small!

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

#312

Post by nonameiguess »

gloryjulio wrote: post #227
bmitc wrote: post #220

I dislike complaining about titles, but I really wish articles, especially a national laboratory, would be more honest about titles. This makes it sound like this is the new "smoking gun" that Mars was so-called Earth-like early on. However, it was my understanding that this was already known. The largest known waterfall was already previously known to be on Mars at one point, and it was already known that Mars had o…

Just a curious question, is Earth's core cooling off like Mars?

Yes, it is. There was a pop-sci book that came out twenty years ago, The Life and Death of Planet Earth, which contains some speculation about the consequences of this: https://en.wikipedia.org/wiki/The_Life_and_Death_of_Planet_E.... They give a low-end estimate of 500-800 million years before plate tectonics stop. Net effect would be the planet becomes uninhabitable by modern day plants and animals well before the sun goes red giant and kills off everything else.

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

#313

Post by Teever »

jajko wrote: post #286
Teever wrote: post #228

Earlier quoted context omitted.

A lot of people feel a strong need to participate in a conversation whether or not they have anything to contribute. So they bring up Von Braun when the topic of space stuff comes up because they don't really know much about space but they want to participate in the conversation so they think of the closest pop culture thing that they can think of. It's one of my biggest pet peeves when talking about space stuff beca…

Any adult who is even vaguely interested in space knows very well who Von Braun was and his history. This is the start of space exploration. So yes I tend to agree with you, but this is a general forum, don't expect much more.

Any recommendations on a forum better suited to the topic?

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

#314

Post by jjk166 »

dullcrisp wrote: post #240
jjk166 wrote: post #226

Earlier quoted context omitted.

> By the standards of the Nuremberg trials, he probably should have been tried and convicted. But he was never even accused, because the US wanted his rocket expertise--by the time of the Nuremberg trials, he was already working for the US Army. Absurd. For starters, by the standards of the nuremberg trials, there's no way in hell he would be convicted. For comparison, among the men actually acquitted by the nurembur…

> Hitler's vice chancellor from 1933 to 1934 and the man who pressured Hindenburg to appoint Hitler to power Are you saying that supporting Hitler before the war should have been a war crime?

No, I'm saying that the Nuremburg trials (rightly) were not a broad inquisition that would convict anyone they could find who was associated with the nazis unless they were under the protection of one of the victorious powers.

Also, fyi the Nuremberg trials were not restricted to war crimes, with many defendants being convicted of crimes against peace or crimes against humanity for their propagation of the Nazi regime and leadership roles in atrocities like the Holocaust. Many of the defendants who were convicted were businessmen, propogandists, and members of the civilian government.

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

#315

Post by TheVespasian »

eloeffler wrote: post #295
TheVespasian wrote: post #221

Earlier quoted context omitted.

> It's a loud silence when someone circles around the topic without mentioning it It's a unique feature of American/Western historiography that would incline you to believe this. I find it interesting we don't have to tack on similar disclaimers when it comes to any other similarly horrible group throughout history; the brutality of the Caesars, the Chinese emperors, the Comanche -- forget about it: we can speak of t…

> we can speak of them dispassionately, as non-temporal observers Well, we can also speak of Wernher von Braun or even contemporary figures that way. It's only more likely that someone comes along and points out that we shouldn't forget about the context. When we speak of ancient history, the context is already forgotten beyond what has been documented. There are no living witnesses nor people who directly related to…

> However we do speak of them passionately anyway, even if the discussion is less emotional. You bringing up the examples that you brought up is a perfect example. People immediately understand what you mean. Anyone who agrees with you will have to feel passionately about these long past events.

I would say an unemotional actor will recognize that those examples are objectively analogical. But that's not really here or there because I'm not saying one cannot have a well-founded moral reaction to the past. I'm saying it's an accident of our location in history that only Nazis receive this treatment -- well-deserved as it may be -- and admittedly one should expect any group to harbor resentment towards a vanquished enemy for some time. But this forum and particularly the context of this thread requires some stationary, objective analysis, which is impossible with the ankle-biting "by the ways."

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

#316

Post by TheVespasian »

the_af wrote: post #301
TheVespasian wrote: post #276

Earlier quoted context omitted.

> Nazism and Fascism are largely influential today but Caesar isn't. Sorry, but this is when I just have to tune out. It's like when people say, "America has no culture," or something similar.

Feel free to tune out. I find your arguments unconvincing. > It's like when people say, "America has no culture," or something similar. I do not live in the US so I couldn't care less about what people say there.

I don't know which country you live in, but it's a claim I've seen made just about everywhere.

Both America and Caesar are so influential that it's difficult for people to recognize their influence. Fish in water, etc.

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

#317

Post by gilmore606 »

mewpmewp2 wrote: post #284
killthebuddha wrote: post #257

Earlier quoted context omitted.

What you're describing is one possible resolution and part of what's interesting. A very big open question is "which, if any, of the known factors are wildly rarer than we think?". Another possible resolution is that most of our estimates are actually ok and there's some other variable that's going to whack us on the head at some point.

I just don't get how anyone can go past the idea that maybe it required freak N amount of specific chemical reactions to happen in a row for the first lifeform and without knowing N the odds could just simply be anything. It seems as if people seem to assume that odds of first life form occuring are high and basically just a matter of time, which doesn't make sense to me.

People go past that idea by noticing that it happened on Earth almost as soon as it possibly could have happened. If we just got incredibly lucky, you'd think the planet would have sat around a while before the big stroke of luck, but it didn't. This is fairly suggestive that abiogenesis is not that unlikely.

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

#318

Post by Kerbonut »

jl6 wrote: post #186
JumpCrisscross wrote: post #181

Earlier quoted context omitted.

> wouldn't rule out that some part of Earth may have had the right conditions for life right from the beginning Even if it was, it wouldn't have survived the impact that created the Moon.

Bear in mind that hypothesized impact is estimated to have occurred around the 4.5Gya mark. That’s still a lot further back than 3.8Gya. And I still wouldn’t categorically rule out microscopic life/life-precursors surviving the event somehow.

What if Mars collided with Earth and that's what killed Mars and transferred life to Earth and also made the moon?

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

#319

Post by pdonis »

jjk166 wrote: post #226
pdonis wrote: post #111

Earlier quoted context omitted.

> I'm not familiar with the extent of his crimes, if any. He was the Nazis' best rocket engineer, responsible for, among other things, the V2s that devastated much of London. By the standards of the Nuremberg trials, he probably should have been tried and convicted. But he was never even accused, because the US wanted his rocket expertise--by the time of the Nuremberg trials, he was already working for the US Army.

> By the standards of the Nuremberg trials, he probably should have been tried and convicted. But he was never even accused, because the US wanted his rocket expertise--by the time of the Nuremberg trials, he was already working for the US Army. Absurd. For starters, by the standards of the nuremberg trials, there's no way in hell he would be convicted. For comparison, among the men actually acquitted by the nurembur…

> The nuremberg trials targetted only the very highest level Nazis

The initial ones did, but there were subsequent ones targeting entire organizations--one of which was the SS, to which Von Braun belonged.

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

#320

Post by pdonis »

defrost wrote: post #269
kmeisthax wrote: post #211

Earlier quoted context omitted.

A significant chunk of the adult male population of Nazi Germany was involved with the genocide. Hitler made sure there was blood on as many German hands as possible. In retrospect the Allies were extremely lenient [0] on Germany and Japan and they probably could have punished them way, way worse. As for Allied war crimes, many of those were only criminalized after-the-fact. For example, the justification for nuking…

The justification at the time for nuking Hiroshima and Nagasaki was field testing two different novel bomb designs .. the urgency came from Germany's surrender and unavailability to use as a test bed and from the rapid depletion of pristine targets in Japan. The H&N bombings followed close on the heels of bombing 72 other cities (including Tokyo) as part of an ongoing HE + incendiary campaign with list of targets. Th…

> The justification at the time for nuking Hiroshima and Nagasaki was field testing two different novel bomb designs

That was probably one reason, but by no means the only one, nor even IMO a very significant one (and the article you link to, which is a good one from a good historian whose entire nuclear secrecy blog is worth reading, does not make the claim you are making--it gives a number of justifications that were made at the time, and the one you give is not one of them).

The Gar Alperovitz book referenced in the article is also worth reading, as is another historical study, Racing the Enemy [1] by Hasegawa. The latter book is not solely about the decision to use the bomb, but more generally about the process by which the war with Japan ended, but that decision and the process that produced it of course play a large role.

[1] https://www.amazon.com/Racing-Enemy-Stalin-Truman-Surrender/...

> it wasn't even certain at the time that this would work as a bomb

AFAIK there was no doubt that the implosion method used in the Nagasaki bomb would work after the Trinity test. And there was never any doubt that the gun-type method used in the Hiroshima bomb would work--they didn't even bother to test it before the Hiroshima bombing. The only question was what the practical yield would be under bombing conditions. But that could have been assessed by bombing tests on uninhabited locations, as was done after the war.

> it was never as clear cut and about swift endings and saving casualities as came to be believed.

People forget that atomic bomb or not the US was already committed to levelling all cities within Japan.

These things are quite true. They do not, however, mean that wanting to field test two different bomb designs was a significant factor. Based on my reading I don't actually think it was one at the political level (what the military people thought was another matter, but the key decisions were made at the political level). Politically, I think the biggest factors involved were uncertainty about what it would actually take to get Japan to surrender, and the desire (at least once Truman came into office) to keep the Soviet Union from playing any part in postwar Japan, and more generally to deter them from expanding further.

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