Sun 1st Feb Show - Robert Zubrin & Mac Tonnies

[Blacknight]

I loved this show and to be honest I could listen to Dr Zubrin talk for hours about mars and terraforming.

He is one of those rare people who really knows what he is talking about and yet is able to explain in a simple and succinct way. I will definitely be buying his book.

Thanks to Gene and David for one of the best shows so far.

I agree. It was an intelligent, informative and interesting two hours. Dr. Zubrin was a stellar guest; direct, insightful, responsive and a legitimate exeprt. He has something to share and knows how to share it in a meaningful way. I'd really enjoy a few hours listening to Michio Kaku (can't get enough of that guy!) and Zubrin.

Great show!

 

[Brian Now]

I agree with everyone else, really good show. I love the subject of terraforming even if I will never see it in my lifetime.

 

[CinderMoltenHowl]

I agree that this was one of the more enjoyable shows.

I tend to put the more enjoyable shows down to two things:

1. The topic being discussed isn't considered by many to be "woo-woo" or "out-there" and has tangible possibilities, backed up with moderate scientific evidence that it can be achieved. Ironical given that the majority of shows are "UFO" based, but even then the more "scientific" episodes tend to rate better.

2. The above coupled with informed guests who don't muck around with their answers (but think about what they say), and are up-front with considering other alternatives posed to them and brain-storming various ideas.

 

[Koji K.]

Am about 30 mins in and I am a little irked that Zubrin seemed to miss David's point about simpler organisms not leaving a fossil record.

Simpler organisms have died out before while more complex ones survived (e.g. bacteria). To say that more complex organisms like bacteria could have survived a trip from Mars while simpler forms of life could not is evidence that life came from Mars BUT somehow to ignore the fact that the very simplicity which makes them unable to survive such a trip is PRECISELY what may have rendered them evolutionarily nonviable here on Earth. Seems like a severe case of willfull blindness to me :/

Kim Stanley Robinson's books rocked, or at least Red Mars and Green Mars did... they sort of droned on a bit when every one of his 100 characters turned into fossils themselves...

 

[Brian Now]

BUT somehow to ignore the fact that the very simplicity which makes them unable to survive such a trip is PRECISELY what may have rendered them evolutionarily nonviable here on Earth. Seems like a severe case of willfull blindness to me :/

Yeah, I wondered about that too. I don't know enough about paleontology or geology to refute him on that. I did appreciate that he brought this up and got me thinking about how the fossil record suddenly displays bacteria out of nowhere. Is this even true though? Or is it more complicated than that?

In the interview, he seemed to indicate as long as you get the atmosphere right and got the peroxides out of the soil you could just start growing plants and trees. But I would think that a genetically natural tree must certainly require more nutrients than the virgin Martian topsoil is going to have in the beginning. But you can get a dandelion to grow about anywhere!

Regardless, lots of good stuff to think about.

 

[Koji K.]

Regardless, lots of good stuff to think about.

True that, didn't mean to sound *too* harsh on him. I hadn't actually ever thought about the strangeness of bacteria being the simplest form of life we have around, and he definitely started me thinking about it.

 

[marduk]

Am about 30 mins in and I am a little irked that Zubrin seemed to miss David's point about simpler organisms not leaving a fossil record.

Simpler organisms have died out before while more complex ones survived (e.g. bacteria). To say that more complex organisms like bacteria could have survived a trip from Mars while simpler forms of life could not is evidence that life came from Mars BUT somehow to ignore the fact that the very simplicity which makes them unable to survive such a trip is PRECISELY what may have rendered them evolutionarily nonviable here on Earth. Seems like a severe case of willfull blindness to me :/

I'm not sure that was his point... what I recall is that he said that nothing simpler than a bacterium has been found in the fossil record or has been found alive today.

This supports the possibility that the simpler organism could have evolved on Mars first since it had water before the Earth did (it was smaller and cooled faster). This organism could have evolved into bacteria and migrated to the earth via meteroids.

I don't think he was saying that it was strong evidence; just that the lack of evidence on Earth supported the possibility. As Friedman says "Absence of evidence isn't evidence of absence."

It would actually be very surprising to me if simpler forms of life could survive the heat, cold, vacuum, hard radiation, shock, and most of all time to survive the migration from Mars to Earth (or vice versa). Bacteria are pretty self-sufficient; they have ribosomes, citoplasma, cell walls, and a nucleoid (a precursor to a well-formed nucleus) with DNA. A little factory that eats, reproduces, etc. They also seem to have the ability to go into extended periods of hibernation... not sure if they could still be viable after the 15 million years that ALH 84001 spent in space but I'd be very suprised if a simpler (and probably more inflexible) organism could handle the trip.

Seems like a precursor might not use a super stable molecule like DNA for information storage for example. Or would have a simpler structure than ribosomes, which handle the transcription and are extremely complex.

I personally think it's pretty likely that if life (or precursors to it) formed anywhere in the solar system it would have rapidly spread throughout the planets through meteor impacts. It may be less a question about where life originated but more a question of where each piece of us evolved from. For example, the proto solar system could have wandered through a interstellar cloud of dust that happened to contain simple proteins. These could have rained down on early Mars, got wet, formed a proto-bacteria. It could have evolved, formed bacteria, and got blasted to Earth. Evolved eukaryotic life. In the impact that formed the [SIZE=+1]Chicxulub[/SIZE] crater that may have wiped out the dinosaurs could have blown chunks of the sea floor containing who knows what back to Mars. Maybe something took and is now putting out methane in geothermal vents back on Mars.

Life is messy.

 

[Koji K.]

I'm not sure that was his point... what I recall is that he said that nothing simpler than a bacterium has been found in the fossil record or has been found alive today.

All your points are good, and I generally agree.. but I probably wasn't too clear about what I was confused about.

This is the thing:

IF simpler forms of life couldn't survive the voyage from Mars, then isn't it just as possible (and far more likely) that they couldn't survive the normal pressures of evolution here on Earth? I mean, that's exactly what evolution IS, and Zubrin seemed completely to fail to grasp this.

Instead of viewing evolution as it is commonly understood in purely Earth-based terms, he bypasses this simple possibility and is placing the missing simpler lifeforms on a voyage from Mars to Earth. I think the Earth-based explanations would have a lot more support, although I'm not evolution expert... but it's not just that Zubrin didn't acknowledge this possibility, he actually outright said that this "wasn't how evolution works."

So it works when simple life-forms travel from Mars to Earth, but not on Earth??

Why make the huge leap from the curious absence of simpler life forms from Earth, to Mars?

 

[status4]

hmm....yes, I'd say one of the best episodes in a while, Zubrin was very entertaining, I enjoyed that one very much, enough to go looking for Zubrin's books. Well done guys.