Sun-like star HD10180 thought to have Earth-sized world Astroboffins probing the skies with a crafty instrument attached to a mighty telescope high in the Andes have found a sun very like our own - which they believe has a planet of similar size to Earth. “We have found what is most likely the system with the most planets yet discovered,” says top sky-boffin Christophe Lovis. “We …
Finally, a post with some sense.
Think this through. Aliens won't invade earth for resources. All their mineral and water needs can be plucked out of space, if they can build an intergalactic spaceship they can easily go and mine a comet for water, or thaw out an ice moon, or bring home a 15 mile long uridium asteroid. Why would they invade for conquest? We'd just fight back and frankly it'd be a choice of complete anihilation or they bugger off home when Arnie spanks one in a jungle, and apart from the Polish builders amongst us we're not exactly big on continual manual labour and therefore piss poor slaves. They also wouldn't invade for our technology , they've got a fuckin spaceship.....WTF do they need a Wii for?
On the other hand, the most likely reason for invading would be like a smokers trip to Amsterdam. Face it, they're just like sailors but in space, so when they find an inhabited planet the first point of call is get wasted and laid.
I call this the universal law of poontang aquisition. Eventually, when technology exceeds the limitations of watching pron, society builds space ships and heads off to another planet where the women/men** may be impressed by intergalactic travel and put out big time.
**delete preference as necessary.
OK, so the lone Earth sized chunk of rock is too hot for Humans. If it was farther away from the star we probably couldn't detect it.
So there might be another Earth sized rock in the right orbit.
And what about the gas giants? Are any of those in the "Goldilocks Zone" of the star? Do any of them have Earth sized moons?
Remember, in Avatar Pandora was not a lone planet but a moon of a gas giant.
This stuff is so cool!! We may not find ET intelligent life but I think we will find ET life within the next 30 years.
Unless of course the MIBs get to the researchers first and neuralize them.
mines the one with the Ray-Bans in the pocket.
Avatar was fiction. I suspect you shouldn't rely on it for your science facts.
I've always thought that the day/night cycle on a moon would be far too erratic, with far too long a "night" when the sun is eclipsed by the host planet, for advanced life to evolve. I suppose you could postulate a really wierd orbit at ~90 degrees to the plane of the ecliptic that might work, perhaps caused by a moon being captured rather than formed, but then the direction of rotation would be all wrong. And I don't know if such an orbit would be stable in the long term, anyway.
GJC
The planet would not really eclipse the sun very often. Think of how often our moon is eclipsed by its planet. While these planets are bigger and their moons might orbit closer to the planets, it would still not be a significant time. You can do the exact calculations yourself -- I once did for moons around a gas giant, which is much bigger than these, and I found eclipses to be neglicible.
What might matter more is if the moons are tidally locked, so their rotation is equal to their synodic periods. This would make for a long day/night cycle. If we look at the big moons of Jupiter for comparison, these are tidally locked and have period ranging from 1.8 days to 16.7 Earth days. 17 days would lead to very extreme day/night temperatures (like winter and summer in Europe), but periods of a few Earth days would not be too bad.
I agree with your comment about Avatar (although I have read that James Cameron was quite careful with his space science), but consider the case of Saturn and Titan. Place Saturn in the "Goldilocks" zone and Titan could become quite a nice place to be for life. The same could also be said for Jupiter and Europa although there could be major issues regarding Jupiter's radiation belts (this might drive evolution faster through mutations though).
Regarding the day/night cycle, I not sure if this is a difficulty. We have a similar problem on Earth inside the artic and antartic circles and life does work in these zones, granted it's hard. A moon of a gas giant will have periods of eclipse but these periods will be short.
What could be more difficult are the orbital dynamics. Going back to Titan again, Titan has an orbital period around Saturn of about 16 days. It is also tidally locked to Saturn, that is it's rotational period matches it's orbital period, so it has a "day" of 16 dfays too. That means that Titan will have 8 (Earth) days of Sunshine and 8 days worth of darkness. This is actually quite less extreme than the situation in our polar circle regions so I feel that this could be quite managable for terresial type life. Eclipses could complicate things as these would last a few days during the daylight cycle but I don't know enough about Titan's orbit at the moment to comment on the frequency of such eclipses, I suspect that Titan's obital inclination takes it out of Saturn's shadow cone quite a lot.
The situation for Europa becomes much more easy as Europa has an orbital period of 3.5 days around Jupiter giving a 1.25 daylight/night cycle(it is tidally locked to Jupiter), much closer to our own. In the cases of eclipses for Europa these will happen every daylight period as Europa is too close to Jupiter to avoid Jupiter's shadow cone, but they should only last a few hours.
In all then, different, perhaps difficult, but not impossible for life to get going and to become complex on such a moon. I think these are very exciting possibilities and given the current state of exoplanet hunting I think these possibilites are more likely than not.
These are exciting times!
Andrew
* start discovering other planets - keep things low key. only discover gas giants unable to support life.
* discover more and more of these and keep the stories in the media. get everyone used to the idea of other planets.
* start discovering more rocky, earth-like planets - although still of course unable to support life due to position in the star system/composition of the atmosphere. have lots of stories in the media about them.
* finally find an rocky, earth-like planet with all the requirements for life, but none of the signs. start media speculation about what kind of life could be hiding there that we can't see due to technology limitations.
* start finding more and more earth-like planets capable of supporting life, all still with no signs of life however. have lots of media stories about them and statements from scientists claiming that it is now only a matter of time before we discover some sort of life on another planet. get everyone used to the idea.
* find some potential signs of life on one of the numerous earth-like planets, but nothing concrete. Have lots of media stories about the kind of life it might be, but always stressing that it is not INTELLIGENT life, rather that someone has discovered an anomaly in the CO2 levels of the planet in question (or something like that), which could indicate some kind of large algae population or something.
* confirm the above. let the media go bananas about finally discovering life on another planet, always stressing that it is simple life and not in any way sentient or DANGEROUS.
* repeat the discovery of simple life on some other planets, and keep finding evidence to support more complex life forms, starting with perhaps some kind of small worm, eventually leading up to finding evidence for some sort of large herbivore creature.
* keep stories in the media about life on other planets, it's type and origin. again, get everyone well used to the idea, whilst always reassuring everyone there is still no evidence for sentient life anywhere.
* launch some sort of probe to a planet which will take at least 50 years to get anywhere and start returning any data.
* meanwhile, discover a SIGNAL. a very simple one. speculation in the media as to the origin and potential threat.
* discover signal is a beacon, leading to further signal discoveries. scientists begin to try and decipher the new, more complex signals. this takes years and years with no results until...
* eventually the probe lauched years earlier starts returning data which turns out to be vital to deciphering the signal. signal turns out to be a "hello" type affair (not the magazine) and confirms there is other intelligent life in the universe.
* it's official. there's other sentient life out there. everyone is stunned. let everyone calm down a bit and keep stories in the media to get people used to the idea we are not alone.
* eventually, after years of speculation as to the type and intentions of any new sentient life, attempts to send return signals and new probes sent out to other planets, the aliens finally land somewhere very public and say hi. No one is that surprised.
* a new era is born.
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Or quite simply that the US government have been directing investigation away from certain areas, know to the 'Grays' and 'Nordics' that have nothing there already, just to direct attention away from the truth..
Then Obama will make a 2hr presentation, introducing the Grays to earth all within the year. Disclosure is coming and the MJ12 group are 70% for it with 30% against... just a matter of time....
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