What might a Gliesian be like?

[BobGreenwade]

As reported in the "Exoplanet Detection News" thread, scientists yesterday detected a planet where Humans might be able to set foot.

 

Gliese 581c has a year 13 Earth days long, 1.6G, an average temperature of 32-104 degrees F, and a dimmer, reddish sun than Sol. The composition and density of its atmosphere are still unknown, as is the planet's rotation, but this is closer to something Earth-like than anything else discovered so far.

 

The question I want to pose is this: assuming its atmosphere is Earth-like and it has native sentient life, what do you think a Gliesian would be like -- especially in Hero System terms?

 

Personally, I start with the gravity; 1.6G would bring in +3 STR unless the natives are considerably smaller. I'd make them only slightly smaller on average, but stocky, kind of like Stallone or Schwartzenegger. Given the dim lighting, I'd give them Nightvision, and a Vulnerability to sight-based Flashes. In appearance I think they'd look similar to us, though probably hairless -- the planet seems to be slightly warmer despite the dimmer light, and hair is a warmth-protector -- and with white or purplish skin.

 

(Anybody want to draw a picture of that? )

[Outsider]

Re: What might a Gliesian be like?

 

How do they know it is 1.6 G? Surface gravity is Mass/Diameter^2, so, depending on the size of the planet (not just its mass) it can vary quite a lot.

 

For the 5 Earth Mass planet in question, for example :

 

Density : Diameter : Mass : Surface Gravity : (density comparison)

8.0 : 1.51 : 5 : 2.19 : (Iron)

5.5 : 1.71 : 5 : 1.71 : (Terra)

3.3 : 2.02 : 5 : 1.22 : (Luna)

1.0 : 3.02 : 5 : 0.55 : (Water)

 

 

1.6Gs assumes the planet is about 20% densier than Earth, and is thus about 1.61 Earth Diameters.

 

 

Edit : I have no artistic skills, sorry

 

Edit #2 : Gonna ask Cancer (our resident astronomer) how they get the diameter.

[Captain Obvious]

Re: What might a Gliesian be like?

 

Heavy gravity might make an ape-like posture worthwhile. Let your arms support some of your weight when you're not actively manipulating something.

[Metaphysician]

Re: What might a Gliesian be like?

 

Well, if the planet is tidelocked, expect some fairly extreme weather. If both sides are still marginally habitable, though, I'd expect the sentients to be evolved from 'edgers': over time they developed tricks that let them expand what counted as the edge zone, until they could expand through most of both lightside and darkside.

[Zachary Butler]

Re: What might a Gliesian be like?

 

Heavy gravity might make an ape-like posture worthwhile. Let your arms support some of your weight when you're not actively manipulating something.

 

 

Better yet, why not dump the humanoid form entirely. A stocky, low-built octoped creature that uses six of its limbs as legs and the other two as arms. I'm getting an image of a six-armed rhinoceros the size of a rotweiler, but with arms.

[BobGreenwade]

Re: What might a Gliesian be like?

 

How do they know it is 1.6 G? Surface gravity is Mass/Diameter^2' date=' so, depending on the size of the planet (not just its mass) it can vary quite a lot.[/quote']I'm not sure how they got that. I had been under the impression that the gravity was one of the first things known as a certainty, and the rest extrapolated, but the Wikipedia article (citing the preprint PDF) gives the gravity as 2.15G (+5 STR). So I'm not so sure.

Well' date=' if the planet is tidelocked, expect some fairly extreme weather. If both sides are still marginally habitable, though, I'd expect the sentients to be evolved from 'edgers': over time they developed tricks that let them expand what counted as the edge zone, until they could expand through most of both lightside and darkside.[/quote']I'd just heard on the NBC Nightly News last night that scientists think that it is indeed tidally locked to the sun. And I think your theory is likely, though I suspect that the Gliesians would be primarily on the light side, with research, mining, and other "necessary" interests on the dark side, sort of like we do with Antarctica. Also, it might suggest Life Support: Need Not Sleep.

Better yet' date=' why not dump the humanoid form entirely. A stocky, low-built octoped creature that uses six of its limbs as legs and the other two as arms. I'm getting an image of a six-armed rhinoceros the size of a rotweiler, but with arms.[/quote']While that's not a bad model for a high-G creature, I don't think 1.6-2.15G is quite that heavy. That'd be more like it for 4+G, I think.

[Basil]

Re: What might a Gliesian be like?

 

Better yet' date=' why not dump the humanoid form entirely. A stocky, low-built octoped creature that uses six of its limbs as legs and the other two as arms. I'm getting an image of a six-armed rhinoceros the size of a rotweiler, but with arms.[/quote']

 

Or something truly different, such as a heptopod with almost complete radial symmetry. For example, the mouth-for-eating could be located on the bottom plate (they have external "armor"), the mouth-for-breathing at the juncture of the upper plates.

 

Oh, and whatever the shape, I'd say they inhabit both the bright and dark hemispheres; unless the orbit is a bit eccentric, the climate will not be too harsh. Though there will be strong winds, they should remain fairly steady and thus predictable.

 

They might be gliders, using running and/or surface irregularities to get air-borne, and using steady winds to glide considerable distances.

 

As well, they'd be adapted to handle a wide range of temperatures.

[Drhoz]

Re: What might a Gliesian be like?

 

Certainly, any species that *could* survive a wider range of temperatures would have vastly increased territory available toiton a tide-locked world, so that's reasonable.

 

I'ld also suspect a degree of infra-vision, given the lower peak energy of Gliese 581's output, and the tendency of life to evolve to utilise the bulk of available resources.

 

On the other hand, for infra-vision to work they'ld need a low body temperature, so they don't blind themselves with their own body heat.

 

Unless they have long unfolding appendages with the heat sensors on the end, the same way the Pioneer and Voyager probes had to avoid the heat of their own power sources?

 

A good design for long-range infravision on Earth is that used by Black Jewel Beetles, who have unique sensors in their armpits that expand minutely when exposed to the distant heat from forest fires. They then swarm in to lay their eggs in freshly roasted pine trunks.

 

So a successful, wide-ranging Gliese 581c-ean would, if you want something really unearthly, have ordinary eyes for use on the lighter parts of the planet, and thermal senses on long, extendable, mobile appendages for peering about in the dark. They'ld also have a stocky bodyplan for extra muscle and insulation on the cold side, and some way of dumping heat fast on the hot side. Quite possibly an erectile crest along the back, above the multiple pairs of walking limbs, that they can use as a radiator in conjunction with the prevailing hotwards wind patterns.

 

That suitably alien?

[Captain Obvious]

Re: What might a Gliesian be like?

 

Watch...when we get there, they'll be humanoids with bumpy foreheads...

[Jkeown]

Re: What might a Gliesian be like?

 

Tidal locking can also occur in a 3:2 ratio, so you might not have a permanently dark hemisphere.

[Drhoz]

Re: What might a Gliesian be like?

 

Tidal locking can also occur in a 3:2 ratio' date=' so you might not have a permanently dark hemisphere.[/quote']

 

true, but then you don't get four legged stalked-eyed radiator creatures with wavy infrared-recievers

[BobGreenwade]

Re: What might a Gliesian be like?

 

true' date=' but then you don't get four legged stalked-eyed radiator creatures with wavy infrared-recievers [/quote']With the exceptionally long days suggested by a 3:2 ratio (would that be 8.3 Earth days long, or 19.5?), I think such a development might actually be even more likely....

[Drhoz]

Re: What might a Gliesian be like?

 

With the exceptionally long days suggested by a 3:2 ratio (would that be 8.3 Earth days long' date=' or 19.5?), I think such a development might actually be even more likely....[/quote']

 

hmm - a good point! especially of theatmosphere is relatively thin, so the temperature changers greatly between noon and midnight

[Basil]

Re: What might a Gliesian be like?

 

Tidal locking can also occur in a 3:2 ratio' date=' so you might not have a permanently dark hemisphere.[/quote']

 

True, though that would pretty much require a fairly high eccentricity. Which is turn would make the conditions even hairier. E.g., those strong winds become even stronger, and more erratic. So the natives are going to need to be able to put up with being picked up, and dropped, by the winds on a frequent basis.

[pinecone]

Re: What might a Gliesian be like?

 

well...High gee says low to the ground and lots o' legs to me, since falls are much more deadly. likely a small surface area so reaction times can benefit from short paths. if it can range through wide environments then it can shed or store heat well.....a big hairy/feathery tarantulla with short powerful manipulating limbs? (Ugly....with a capitol Ugh...)

[BobGreenwade]

Re: What might a Gliesian be like?

 

hmm - a good point! especially of theatmosphere is relatively thin' date=' so the temperature changers greatly between noon and midnight[/quote']Actually, I think it would work better if the temperature changes aren't that extreme. It's the presence or absence of light that makes the difference to my mind.

well...High gee says low to the ground and lots o' legs to me' date=' since falls are much more deadly. likely a small surface area so reaction times can benefit from short paths. if it can range through wide environments then it can shed or store heat well.....a big hairy/feathery tarantulla with short powerful manipulating limbs? (Ugly....with a capitol Ugh...)[/quote']For a high-G setting, that's quite true; but this planet isn't quite high enough to warrant that radical of a change. I'd start this at 3G, and call it more likely at 5G and up. At 1.6-2.1G I think the humanoid model would be just fine.

[Basil]

Re: What might a Gliesian be like?

 

At 1.6-2.1G I think the humanoid model would be just fine.

But boring!

 

 

[Metaphysician]

Re: What might a Gliesian be like?

 

The important question is, what do they need to become a *sentient, technologically advanced* species. Number one being, manipulative appendages.

[Drhoz]

Re: What might a Gliesian be like?

 

The important question is' date=' what do they need to become a *sentient, technologically advanced* species. Number one being, manipulative appendages.[/quote']

 

hence the design i'm putting together - the forward pair of walking limbs are big crab-claws, on which it knuckle-walks - good for walking, digging, and cutting visiting astronauts in half. Next to the mouth are fold-away fine manipulators, long enough to hold items such as human organs up in front of the eyes for study. Alongside THOSE are the even-longer heat-sensor limbs.

 

plus long whiskers from each joint so it doesn't blunder blindly about in total darkness.

[BobGreenwade]

Re: What might a Gliesian be like?

 

hence the design i'm putting together - the forward pair of walking limbs are big crab-claws, on which it knuckle-walks - good for walking, digging, and cutting visiting astronauts in half. Next to the mouth are fold-away fine manipulators, long enough to hold items such as human organs up in front of the eyes for study. Alongside THOSE are the even-longer heat-sensor limbs.

 

plus long whiskers from each joint so it doesn't blunder blindly about in total darkness.

I'm rather liking this model.* Would the knuckle-walking be represented as Extra Limbs?

 

*Except, of course, for the part about cutting visiting astronauts in half and ripping out their organs. I've grown rather fond of most of my internal organs. I'd like to find something new in the way of bronchial tubes and a colon, but on the whole I'd like to keep everything in place until viable replacements can be found.

[Sundog]

Re: What might a Gliesian be like?

 

Might I suggest that this creature be exo-skeletal? In a 1.6 G + environment, impact resistance would be a valuable survival trait. In addition, it could, like a number of crab species, have solid, non-living material for the lowest section of leg, thus obviating any need to keep that section warm - and providing much needed insulation for the rest of the body against the extremely cold ground of nightside, or the far too warm ground of dayside.

[Clonus]

Re: What might a Gliesian be like?

 

Might I suggest that this creature be exo-skeletal? .

 

Endoskeletions are far better for dealing with gravity. That is why the really big land creatures on Earth are all endoskeletal

[Metaphysician]

Re: What might a Gliesian be like?

 

For extra impact tolerance, perhaps a thicker outer layer of fat or some similar tissue along the skin, to cushion blows.

[pinecone]

Re: What might a Gliesian be like?

 

Actually' date=' I think it would work better if the temperature changes [i']aren't[/i] that extreme. It's the presence or absence of light that makes the difference to my mind.For a high-G setting, that's quite true; but this planet isn't quite high enough to warrant that radical of a change. I'd start this at 3G, and call it more likely at 5G and up. At 1.6-2.1G I think the humanoid model would be just fine.

 

At 1.6 Gee a fall does about 60% more impact...so a fall of say 10 feet goes from Ouch! To "is there a doctor in the house?" I'd assume that evolution would favor the most conservative design. Though evolution does seem to play a few jokes along the way.

 

I'd be suprised to see a biped at 1.6 gees, but maybe a biologist can explain exactly how wrong I am....

[Drhoz]

Re: What might a Gliesian be like?

 

Might I suggest that this creature be exo-skeletal? In a 1.6 G + environment' date=' impact resistance would be a valuable survival trait. In addition, it could, like a number of crab species, have solid, non-living material for the lowest section of leg, thus obviating any need to keep that section warm - and providing much needed insulation for the rest of the body against the extremely cold ground of nightside, or the far too warm ground of dayside.[/quote']

 

i like that reasoning