"Extraterrestrial" Decision

[skwirlinator]

****Attempt at no spoilers****

So if you watched Discovery Channel's Alien Planet AND National Geographic Channel's Extraterrestrial you got to witness multiple lifeforms extrapolated from Earthly observations based upon current scientific knowlege and theories.

The thing that I noticed with both of these shows was the lack of ecology. I know that the shows only profiled a few probable species but there was no reference to other species and sub-species or even variations. (well I am wrong in the whale hunter/worker things) But as it was presented the only food for such was such. It just seemed so limited.

Of the species that were presented how accurate were they to a possible life form.

How likely is it that the planet could be locked in such a state long enough for life to evolve that advanced. I don't think such a planet could exist in that state.

I do however believe the Moon could be possible.

Which show was better?
That's a loaded question.

Which show had the better 'Science'?

[skwirlinator]

Didn't ANYONE see these shows?

:o

[Lance]

I saw Alien Planet.. I have Extraterrestrial recorded. As soon as I watch it I'll let you know.

Didn't ANYONE see these shows?

:o

No! :oops: :oops: :oops:

[ToSeek]

We watched National Geographic's Extraterrestrial last night and thought it was pretty lame. For one thing, it could have used better editing: some scenes were repeated three and four times, and the same ideas - and phrasings! - were used over and over again. I was about ready to start a drinking game for the show: "Sip whenever Michael Dorn says 'in the next few years.'" "Sip whenever they show a mudpot sitting right in the mouth of its burrow waiting to be eaten." It just didn't seem to have enough material for a two-hour program.

[Platinum Rhymer]

I saw Alien Planet but missed Extraterrestrial.

I thought Alien Planet was pretty awesome.

[skwirlinator]

I think Alien Planet was better too!

[Gillianren]

we don't get National Geographic. it's only available around here if you get digital cable (or a dish, I suppose). missed the one on Discovery, too, but I've no doubt they'll rerun it until we're all sick to death of it.

[LynnF1]

Saw both.

I have but a limited science background, so I can't comment too much on the specifics presented, although I find ToSeek's and Skwirlinator's comments valid - I noticed a lack of tails swishing at insects, plain old vermin taking up niches and such. I thought Alien Planet the more imaginative. I thought the huge flying things in Extraterrestrial an interesting take on whale sharks.

I was simply heartened to see actual scientifically-based and forward-looking programming, rather than the usual Grays/Lizards Are Among Us! type shows, which is how it seems alien life is usually treated.

My $0.02.

[skwirlinator]

I have been interested in scientific extrapolations of what alien life would be like for a very long time now. Now that CGI has taken root It's not surprising these types of shows are comming out. Discovery Channel's "Walking With" series is not too bad and I have been enjoying them. I think National Geographic Channel only made Extraterrestrial because of competition with the Discovery Channel.

The whole concept of Competition to win viewers in science puts a bad taste in my mouth! In my pipedream I see all science working together as one to advance mankind's knowledge. I lnow it isn't true but it's how I look at shows like NOVA and National Geographic and Discovery. I watch these shows and can't help but think "This is where we are in science" but it is really driven by ratings and money. Raw science is boring. Carl Sagan pioneered the idea to bring science to the masses and make it exciting. He hooked me!

As for the two shows, Alien Planet looked more 'thought out' and better edited. The graphics were better but I believe the 'science' between the two show was about the same.

Extraterrestrial's Planet was a bit fishy not rotating. I doubt that a planet like that could have those conditions for that long of a time period. How could the molten Iron core and solid Iron core generate a magnetic field to divert the stars ejecta. The atmosphere would have been blown away a long time ago if it ever formed at all.

[Romanus]

For what it's worth, scientists have done quite a bit of modeling about what the climate on a tidally-locked planet around a red dwarf would be like; I have a scholarly article about this topic myself, though its buried in the tons of printouts I accumulated in school. I think the consensus is that a planet with a dense enough atmosphere could circulate heat around efficiently enough to prevent from becoming unbearably hot or cold on either side, though as the program noted conditions would be most favorable near the terminator.

RE Coriolis effect:
IIRC, Coriolis force is directly proportional to rotation rate; a tidally-locked planet orbiting every 80 days *might* still have enough available to work a planetary-scale cyclone into a spiral, though I admit I don't have the background to prove it. However, as on Earth I think the force would be opposite between the two hemispheres; thus, the show probably should have shown two giant cyclones spinning in opposite directions near the substellar point, one north and one south of the equator.

The magnetic field issue is interesting as well, but let's not forget that our own Mercury, which rotates only every ~60 days, has a magnetic field strong enough to divert the solar wind. If the planet still has a small molten core, as most scientists conclude, and the magnetic field is produced by a dynamo effect, then I don't think it's a stretch to conclude that a much larger, more active planet rotating only 20 days longer could have a field strong enough to deflect the stellar wind.

The only thing that I found a little disconcerting about "Extraterrestrial" is that I think that it would be difficult even for TPF to find an Earth-mass moon around a giant planet; I'm guessing its IR signature would be easily swamped by its parent, though we could probably detect the moon by radial velocity oscillations on the planet easily enough.

As to which program I think was better, it's a tough call. I personally enjoyed "Alien Planet" more, because it was dramatic and fast-paced, even if not particularly realistic. However, I think the science in "Extraterrestrial" was much better, being as to that it did not start out as an artistic exercise, as "Alien Planet" did. So all in all I'd say it was a dead heat.

[A Thousand Pardons]

The magnetic field issue is interesting as well, but let's not forget that our own Mercury, which rotates only every ~60 days, has a magnetic field strong enough to divert the solar wind. If the planet still has a small molten core, as most scientists conclude, and the magnetic field is produced by a dynamo effect, then I don't think it's a stretch to conclude that a much larger, more active planet rotating only 20 days longer could have a field strong enough to deflect the stellar wind.
yeah, a planet's rotation probably has nothing to do with the generation of its magnetic field.

[skwirlinator]

Really? I thought the magnetic feild would be 'generated' by the planets rotation as long as there was a solid and liquid Iron core? Magnetic induction?
It's my understanding that a pole reversal is linked to the behavior of the liquid core of the Earth. That's where the concern is. During such a reversal the protective heliopause is interrupted and the Earth is vulnerable to CME.

I could be wrong and probably are. But thats one of the reasons I come to this site, To be Enlightened!

[A Thousand Pardons]

Really? I thought the magnetic feild would be 'generated' by the planets rotation as long as there was a solid and liquid Iron core? Magnetic induction?
For the most part, the magnetic field rotates with the planet, so the generation of the field is independent of the roation.

It's my understanding that a pole reversal is linked to the behavior of the liquid core of the Earth. That's where the concern is. During such a reversal the protective heliopause is interrupted and the Earth is vulnerable to CME.
The magnetic field, especially in the case of the earth, is almost certainly generated in the liquid core. However, all sorts of rocks on the surface of the earth have the magnetic field frozen into them, so there would be a magnetic field, however probably slight, even if there were no liquid core remaining.

PS: The strong bipolar feature of the earth's magnetic field is obvious, at the surface. However, the relative strength of the quadrapole (and shorter wavelength features) is diminished the farther from the source. If the earth's magnetic field is projected down to the core-mantle boundary (CMB), the strength of all the components is nearly the same. That suggests a chaotic regime in which the bipolar field is somehow aligned to the rotation by secondary effects not related to the actual generation--and it means that if the bipolar field were to weaken while reversing, the other components would diminish also, and there's not much support for that sort of notion. The energy source of the magnetic field would have to weaken, or almost disappear. And then reappear, when the field re-establishes itself.

[skwirlinator]

While it doesn't disappear during a reversal it splits into multiple tiny poles at which time the Earth is vulnerable. Even if that planet had resonance magnetics what keeps the atmosphere from being swept from it? I just cant see how that planet could have an atmosphere for 5 billion years and be stable enough for advanced life to establish itself, without some kind of spin.

[skwirlinator]

It just occured to me that even tho we cant 'feel' the spin of the Earth it still affects us. If we were to land on a planet that does not spin it would affect us. But I don't know what that would be. We must be compensating for the spin somehow. Perhaps that is what allows us to evolve 'movement' A planet with no spin would not perpetuate movement and life could not evolve- gravity would prevail.

My eyes are starting to cross up now...

[A Thousand Pardons]

While it doesn't disappear during a reversal it splits into multiple tiny poles at which time the Earth is vulnerable.
That's speculation. I seem to remember that the recent research showed that it wasn't even true, although I'll have to look at it again to be sure.
Even if that planet had resonance magnetics what keeps the atmosphere from being swept from it? I just cant see how that planet could have an atmosphere for 5 billion years and be stable enough for advanced life to establish itself, without some kind of spin.
What does spin have to do with keeping the atmosphere?
It just occured to me that even tho we cant 'feel' the spin of the Earth it still affects us. If we were to land on a planet that does not spin it would affect us. But I don't know what that would be. We must be compensating for the spin somehow.
Sure, there is the coriolis effect to be taken into account, but the biggest effect is just to change our idea of "down". If someone in South Dakota were to drill "down" in a straight line, they'd miss the center of the earth by tens of kilometers. Half of it is because the earth bulges out at the equator (because of centrifictional force) and attracts the plumb bob, and the other half is because the plumb bob is forced out itself.

[skwirlinator]

What does spin have to do with keeping the atmosphere?

Only if the spin affects the planets magnetic field, 'SOMETHING' has to keep the atmosphere from being blown off into space. They depicted the Red giant as having 'Flares' that the inhabitants had to seek shelter from. They depicted the star as overhead but the life zones were on the sides. At 1 bar the atmosphere would 'Blow' off the planet with the first starflare. (It's NOT a solar flare because it didn't originate from 'Sol').
I have pulled up the site interactive
http://www.nationalgeographic.com/channel/extraterrestrial/

AURELIA is
1 earth Mass
1 earth Radius
its Year and Day is 80.3 earth days
its star is a red dwarf
its atmosphere is 78%N2, 21%O2, >1% h2o, >1%AR
at 14.5 psi (1bar)
4.7 billion years old

I'm not sure a red dwarf can have a CME but at 80.3 day year it must be very close and it would only take 1 CME to blow off the atmosphere at which they depicted flares happening frequently enough to warrant an evolutionary development. At 1 bar it would take a flare psi of 15psi to overcome 15psi would blow it off the planet. I'm sure there are some smart people that could calculate what it would take to blow 14.5 psi atmosphere off a planet that has no protective field. Mars spins but it is geologically dead. It barely has an atmosphere. If it once did, what happened to it? It got blown into space from the solar wind when the mag field collapsed.

I am not trying to prove or disprove anything its just what i'm thinking, That planet couldn't have life on it as it is described. If it did then it wouldn't be as they described it because of the dynamics of the planet's lack of spin. The star would not be overhead-it would be to the horizon. Life would evolve lopsided to account for this.

Alien Planet is just better science.

I'm wondering How the BA would assess these shows?

[A Thousand Pardons]

What does spin have to do with keeping the atmosphere?

Only if the spin affects the planets magnetic field, 'SOMETHING' has to keep the atmosphere from being blown off into space.
As I said before, the spin probably does not affect the planet's magnetic field. It's more probably related to whether it is geologically dead.

I'm not sure a red dwarf can have a CME but at 80.3 day year it must be very close
The mass of a red dwarf is around a tenth of the Sun, so it wouldn't have to be too close.

Mars spins but it is geologically dead. It barely has an atmosphere. If it once did, what happened to it? It got blown into space from the solar wind when the mag field collapsed.
Mars is a tenth of the size of the Earth. It's surface gravity is less than half. So, it cannot hold on to an atmosphere as strongly. Venus is closer to the Sun, but its gravity is comparable to Earth's.
The star would not be overhead-it would be to the horizon. Life would evolve lopsided to account for this.
You mean, their left side bigger than their right side? :)

[gopher65]

errr. I could be wrong, but I thought Venus had almost 0 magnetic field? And not only is it closer to the sun than Earth, but it manages to have an atmosphere far denser than ours.

[skwirlinator]

errr. I could be wrong, but I thought Venus had almost 0 magnetic field? And not only is it closer to the sun than Earth, but it manages to have an atmosphere far denser than ours.

So what keeps the atmosphere on it? Just gravity?

[Halcyon Dayz]

Just gravity.

[tracer]

It's my understanding that a pole reversal is linked to the behavior of the liquid core of the Earth. That's where the concern is. During such a reversal the protective heliopause is interrupted and the Earth is vulnerable to CME.
And, if you believe a certain not-too-old movie that's panned elsewhere on this site, the Earth is also vulnerable to killer microwave beams from space, pigeons going berserk, lightning storms that can make stone buildings detonate, and getting held up in the path of a giant flaming aerosol spray can.

[skwirlinator]

It's my understanding that a pole reversal is linked to the behavior of the liquid core of the Earth. That's where the concern is. During such a reversal the protective heliopause is interrupted and the Earth is vulnerable to CME.
And, if you believe a certain not-too-old movie that's panned elsewhere on this site, the Earth is also vulnerable to killer microwave beams from space, pigeons going berserk, lightning storms that can make stone buildings detonate, and getting held up in the path of a giant flaming aerosol spray can.

I actually got that Idea from NOVA
http://www.pbs.org/wgbh/nova/magnetic/reversals.html

http://www.pbs.org/wgbh/nova/magnetic/reve-drives.html

[SkepticJ]

Just gravity.

Magnetic fields keeping a star from blowing a planet's or moon's atmosphere away is only needed if its gravity is low, like Mars. What magnetic fields do that are important for Earth-sized worlds is shield a lot of the radiation out. Perhaps life can evolve to handle radiation like the Earth would have without its field and ozone layer.

[publiusr]

The art from Alien planet was better--but the Gas Giant Moon as life-bearer was dead on as far as I could tell. Sky whales? Don't know about that-but the make up of the moon itself seems very believable.

Here is hoping a somewhat icy version exists around 47 Ursae Majoris.

[Brad_Smith]

I liked both programs. I thought that each presented unique scenarios on how life might evolve elsewhere in the Universe; I loved Wayne Barlowe's Expedition and was thrilled to see it visualized in Alien Planet.

[R.A.F.]

We watched National Geographic's Extraterrestrial last night and thought it was pretty lame. For one thing, it could have used better editing: some scenes were repeated three and four times, and the same ideas - and phrasings! - were used over and over again. I was about ready to start a drinking game for the show: "Sip whenever Michael Dorn says 'in the next few years.'" "Sip whenever they show a mudpot sitting right in the mouth of its burrow waiting to be eaten." It just didn't seem to have enough material for a two-hour program.

You know, I read this back on the first (before I saw Extraterrestrial) and thought, surely Toseek was exaggerating...it couldn't possibily be "that" bad.

Well now that I've seen it, I must admit that Toseek's pretty much covered everything that was wrong with Extraterrestrial.

If you started a drinking game using this show (as was suggested) by the end you'd be an alcoholic.

The only thing that made it watchable was that I "DVD'ed" it. My DVD recorder has the option of watching at double speed, yet being able to hear dialogue "pretty much" normal...ie, the pitch is equalized. So I watched it in 45 minutes as opposed to an hour and a half...so I "saved" myself 45 minutes!!! :lol:

They did keep saying (and showing) the same stuff over, and over, and over, and over, and over again...I guess to "flesh out" what was essentially a one hour show.

I haven't seen Alien Planet yet. Hopefully it is better.