Hard Light Productions Forums
Off-Topic Discussion => General Discussion => Topic started by: Flipside on August 25, 2004, 12:39:37 pm
-
http://story.news.yahoo.com/news?tmpl=story&u=/afp/20040825/sc_afp/space_astronomy_planets
Not much to go on yet, but interesting nonetheless :)
-
'super earth'
Neat.
-
Proably just my general ignorance, but I though that there was millions if not billions of planets discoevered outside our solar system. But I guess I was wrong, in which case this is a very exciting find indeed.
And only 50 light-years away. Why, we're practically neighbors ;) ;)
-
Interesting ...
-
Originally posted by Rictor
Proably just my general ignorance, but I though that there was millions if not billions of planets discoevered outside our solar system. But I guess I was wrong, in which case this is a very exciting find indeed.
And only 50 light-years away. Why, we're practically neighbors ;) ;)
Not really. Planets in other solar systems are really hard to see, that's why up to now mostly gas supergiants had been positively identified...
-
It's 14 times the mass of Earth? That's a big motha f*ckin' rock, motha f*cka!
-
Originally posted by Rictor
Proably just my general ignorance, but I though that there was millions if not billions of planets discoevered outside our solar system. But I guess I was wrong, in which case this is a very exciting find indeed.
And only 50 light-years away. Why, we're practically neighbors ;) ;)
The theory is that there are millions of planets out there but until now we've only found a small number of them. They've found lots of Jovian and super-jovian planets cause until now that was pretty much all we could find. This on the other hand is a rocky planet with an atmosphere. What's more if the atmophere contains significant quantities of oxygen it's almost certain that there is life on the planet.
From the original story However, there is the tantalising question as to whether it lies within the "Goldilocks Zone" -- a distance from its star that is not too hot, not too cold, just right.
I guess by this they mean the zone which Europa, the biggest chance for life in the solar system apart from Earth is OUTSIDE of? :rolleyes:
I wish astrobiologists would stop talking about habitable zones. The science moved on about 20 years ago.
-
the planet's orbital period is 9.5 days. I don't think thats very good for water
-
Originally posted by karajorma
I guess by this they mean the zone which Europa, the biggest chance for life in the solar system apart from Earth is OUTSIDE of? :rolleyes:
I wish astrobiologists would stop talking about habitable zones. The science moved on about 20 years ago.
Not necessarily. The "goldilock's zone" that they speak of isn't necessarily a set band around the primary star. Europa is close to Jupiter, and would have NO chance for life if it were not close to Jupiter. Jupiter was almost a star is the cosmic sense, as it's mass is only two-three orders of magnitude off. Jupiter emits certain forms of radiation, primarily infra-red, nearly as much as a star. So what you have with Jupiter, and any other similar gas giant of its mass/composition, is a mini-system of sorts. Europa is lucky in that it may be in an acceptable zone to sustain certain forms of life. It's surface may be frozen, but not all the way down... :devil:
-
Somewhere there is life in this Galaxy.. maybe in that planet that would be kinda cool
:welcome:
Vaelinx :)
-
Originally posted by Vaelinx
Not necessarily. The "goldilock's zone" that they speak of isn't necessarily a set band around the primary star.
That's exactly what they say it is in the article. Hence my condemnation of it.
Originally posted by Vaelinx
Europa is close to Jupiter, and would have NO chance for life if it were not close to Jupiter. Jupiter was almost a star is the cosmic sense, as it's mass is only two-three orders of magnitude off. Jupiter emits certain forms of radiation, primarily infra-red, nearly as much as a star. So what you have with Jupiter, and any other similar gas giant of its mass/composition, is a mini-system of sorts. Europa is lucky in that it may be in an acceptable zone to sustain certain forms of life. It's surface may be frozen, but not all the way down... :devil:
I know full well why Europa is a good candidate. In fact it's the squeezing of the planet by Jupiter's gravitational field not it's radiation output that makes it viable. I know full well about the oceans below Europa and the fact that it may have black smokers similar to Earth. That doesn't change my viewpoint one bit.
The whole concept of habitable zones is bollocks. 20 years ago black smokers were considered uninhabitable. Any part of a system with conditions similar to a black smoker would be considered impossible for life but now we know that not only are they good conditions for life but that on top of that life on Earth may have started in one.
The simple fact is that liquid water isn't a requirement for life. There are other ways to get the complexity required. Water is however a very good solvent and as such life becomes more likely when it is present. Scientists get hung up on looking for planets exactly like Earth. In fact there are probably scientists ruling out this newly discovered planet because the gravity on the planet would be too high. Like that makes a difference to the formation of amino acids or whatever chemicals life on this planet could have chosen to use. :rolleyes:
Life may be able to evolve in other conditions other than the ones we have here on Earth. Just because life did evolve here doesn't mean that this is the only possibility.
Anyway :welcome: Vaelinx. Enjoy your stay :)
-
We are Carbon based life, and there are a whole LOT of other elements :D
-
Originally posted by PhReAk
the planet's orbital period is 9.5 days. I don't think thats very good for water
I noticed that too. The star may be a brown dwarf though, which would mean much smaller solar radiation output and therefore a habitable zone that extends very close to the star. And that concept is far from obsolete as some have indicated; life needs a sustainable energy source to survive, while not one so intense that it destroys anything less dense than solid rock. Mercury, for example, is not a candidate for life in any form, because our sun has not only fried the surface by its proximity but quite possibly cooked much of the surface rock away over the past 5 billion years. The outer planets and moons don't recieve enough solar radiation to sustain life, and none are large enough to still have active geothermal activity either. Europa, on the other hand, is a bit of an exception; the amount of solar radiation it recieves is less than the commonly assumed requirements for life, but it is protected to a large degree by Jupiter's gravity well that serves to sweep the inner solar system of smaller debris that will have serious disruptions on life (it has also likely helped Earth avoid a constant bombardment of asteroids as well) and it does recieve some boons from Jupiter's radiation output and magnetic field as well.
EDIT: In other words, habitable zones are more about the net amount (and to a degree, the concentration) of solar radiation on a planet, not between two fixed radii out from the star.
I did read somewhere that planets could travel in a much less circular orbit and still meet the requirements for habitability, maybe that's what's happening here. It just seems a little far-fetched that something that close to a star could sustain liquid anything, and I really don't know how life would evolve from solid rock.
-
Exactly. Silicon isn't quite as good a choice but silicon analogues can be made of many simple carbon chemicals.
Besides there is no reason why you can't make complex molecules that react in liquid methane as long as they are non-polar and don't require metal ions the way our bodies do.
Sure you might not get complex life in liquid methane that often but I'm talking about life not intelligent life.
-
jdjtcagle, it's actually a bit more limited than that. Elements that could potentially form the macromolecules required for life are basically restricted to Group 14.
-
Didn't know that... :)
-
Originally posted by StratComm
Mercury, for example, is not a candidate for life in any form, because our sun has not only fried the surface by its proximity but quite possibly cooked much of the surface rock away over the past 5 billion years.
You're right because we now know that mercury's rotational period is different from that of it's orbit but until recently Mercury was thought to be a one face planet which rotated as quickly as it orbited the sun.
Now it follows that if the planet is blisteringly hot on one face and freezing cold on the other there must be a region between the two extremes.
I doubt Mercury does have life since it has no atmosphere and since it's now proven that it isn't a once-face planet but if it was the possibility existed that there might be life on the planet.
See what a load of crap habitable zones are now? Basically all that is needed is energy. This doesn't even have to come from the star. It doesn't in the case of Europa after all.
-
However, iirc, even on Earth we are constantly finding different pressures, temperatures etc in which to make carbon and oxygen molecules react in different ways, so the possibilities aren't as limited as it seems :)
-
Kara: Yep, the radiation from Jupiter is enough...
-
You don't need the sun at all, actually. Take a look at deep-ocean vents. The energy for those ecosystems is all geothermal and chemical.
-
Exactly, and if life on Earth did develop in the 'Pea Soup' environment that most geologist suspect existed at that time, our atmosphere was almost as thick and nearly as poisonous to humans as Venus at the time that life first started here. Much like a deep-sea vent, in fact.
I think that the question has been raised before as to whether Venus is, in fact, a pre-life body?
Oh, and Kara, apparently there are suspicions of Deca-mile deep chasms in the surface of Mercury, possibly down to the mantle caused by heat splitting :)
-
Kara, without an atmosphere, you're either being hit with solar radiation or you aren't. The surface will transmit some heat as well, but the deliniation between hot and cold is pretty fixed, and very narrow. Subsurface life, maybe, but the likelyhood of life developing in dry, solid rock (dry in any chemical form, not just H2O) is very low. The moon has issues with that, and it's in the same radiation exposure level as Earth. We're pretty much in agreement about everything but terminology though, if you'll read the rest of my last post.
With Jupiter, it's so close to being a small brown dwarf that it isn't even funny. I still think that most of the superjovian planets being spotted right now will actually be reclassed sooner or later to small stars.
EDIT: Energy in a solar system ultimately comes from one of two places: a star, or the remenants of the system's formation. Geothermal energy on our rock would have long ago been exhausted if we didn't recieve heat from our star, and even then it's going to run out of heat sooner or later. Radioactive materials can prolong the life of geothermal activity, but it's a fixed length process. Add to the fact that geothermal activity has a nasty tendency to start and stop in most situations where it can occur, and it makes life that much more difficult to harness. Black smokers tend to be a bit more fixed, but they have the drawback of requiring a liquid medium to keep the geothermal energy concentrated and harnessable, and do not release enough energy on their own to maintain a liquid body of water. Chemical energy is completely useless on its own in the long term, because it requires another energy source to replenish it. Solar fusion is the only other long-term sustainable energy source that occurs naturally and can be used by protolife for replication and evolution. Fairly simple if you ask me. The radiation output of Jupiter is somewhat of an anomoly, so much so that it almost qualifies as a secondary star when it comes to a source of radiation for its moons (has anyone ever figured out exactly why jupiter puts out more energy than it absorbs, anyway?) but it's still close enough in to the sun for its moons to benefit from solar radiation as well. It suppliments energy from the sun, not replaces it.
-
Thanks for the article. Now I finally have something to write about for my English class.
-
Originally posted by Flipside
Oh, and Kara, apparently there are suspicions of Deca-mile deep chasms in the surface of Mercury, possibly down to the mantle caused by heat splitting :)
I hadn't heard that. Doubt there is life in them though. Considering the heat of the surface side of mars and the lack of any solvent in which complex chemisty could happen.
Could be proved wrong though :)
Originally posted by StratComm
We're pretty much in agreement about everything but terminology though, if you'll read the rest of my last post.
I agree that the likelyhood of life on Mercury is low but it's not impossible by a long shot. Similarly life could exist on at least 3 of Jupiters moons, on Titan and on Triton. Given that we're now saying that life can exist anywhere between Mercury (Venus if you still can't accept the possibility of a one-face Mercury) and Uranus doesn't that make habitable zone theories a joke?
When astrobiologists talk about habitable zones they are actually talking about that narrow area where liquid water exists. But as I've already stated that's nonsense since we can hav life without water.
So lets drop the whole concept of habitable zones and simply examine each planet on a case by case basis instead.
-
I'm not certain they'd support life, but I'd just love to see some of this stuff before I die, the chasms on Mercury, Mons Olympus on Mars, the Methane Lakes that are suspected to be on Europa etc
Ah well, dream on Flip :D
-
Methane lakes on Titan, silly ;)
-
LOL Oooops, yep, it's all that talk of Europa ;)
-
I agree flip. That stuff must look beautiful :)
-
Well, it was because I used wonder what these places are like that I sort of got into rendering in the first place :-
(http://www.aqsx85.dsl.pipex.com/titan.jpg)
I might actually break out Vue again, I forgot how much fun it was ;)
-
On the subject of habitable zones, I've always considered it as: habitable for humans
Keep in mind that a lot of this search isn't really for pure science and knowledge but it's because some people want to find a sister planet to Earth for future colonization or if need be, conquest.
-
Yep, the ultimate goal is to find a 'Sweet Spot' planet, but sometimes you can learn a lot about the ocean by looking at the stones ;)
-
does anyone else think "Mu Arae" sounds like a realy cool name for a star system?
-
Decent. I really prefer the ones including the first 4 letters of the Greek alphabet though.
-
that article is wrong about the habitable zone, BTW. It doesn't need to have liquid water that is neither boiling nor frozen. some types of algae can clearly be seen thriving in the boiling yosemite nat'l park springs, and bateria has been found in core samples from miles below the arctic. both these conditions are, btw, worse for life than many places on mars, and hopefully, Europa.
-
Thank you for the welcome!
Let's put the life thing into perspective. Thus far, we have found one planet with life (still holding out for Mars though). And even if life is found on Mars, it is far to similar to Earth (within that silly "goldilocks zone") to draw any huge conclusions about how life may originate differently than it may have here, in a cosmic sense we're neighbors.
However, we have very few data points. We have not explored any other planetary bodies extensively. We've scratched the surface of Mars, looked really hard at the moon...
So far, we *know* that life can be supported on this little rock we call home. That is our only frame of reference. Unless we can experimentally create life in another environment, we have only one data point (on the planetary scale). Now, this does in NO way DISprove that life can come about or be supported in other environments. We just don't know. It also doesn't PROVE that another environment can have life. Until we find it or create it, we cannot prove the existence of another form of life. Without data, it's just math and conjecture.
Theoretically, life should be all over the universe... depending on the set of theorems you start with... :)
I personally hope that we find life all over our solar system and hopefully galaxy. Who knows, maybe someday we'll find some Vasudans to shoot at. ;7 Or Shivans to get kicked around by... :devil:
The other alternative is that this galaxy is a very lonely place... We just don't know yet... Hell, we don't even know our own origins... But current theories say we needed water... So we look for places out there that have water and heat and atmoshpere... At least we can move in if noone else is home :p
-
You're welcome Vaelinx.
I agree with you fully about us only having one data point. Which is why I find it so silly to extrapolate from that and say life can only exist on an Earth like world.
Personally I would love to see life found on Europa or evidence of it having existed (or for that matter still exisiting) on Mars.
-
Carl Sagan came up with a hypothetical lifeform that swam in the mineral-rich outer layers of Gas Giants in very much the same way as deep sea lifeforms operate in, what we believed to be, 'non-life capable' water on Earth, if you can track down the book 'Cosmos', it's old, but very well worth a read :)
-
I'm currently reading "What does a martian look like" by Jack Cohen and Ian Stewart. It's a pretty interesting book on what might be out there :D