ElbowRocket
Member
I wonder if the other civilizations out there fight and disagree as much as we do...
EDIT: note: just my thoughts about thisI wonder if the other civilizations out there fight and disagree as much as we do...
Gliese 436 B is my new favourite planet. Not because of its catchy name, but because of one of the most unusual properties found anywhere in our solar system. Gliese 436 B is a Neptune sized ice world, yet orbits its star at a very toasty 4.3 million miles. Thats almost fifteen times closer to its star than Mercury is to the sun. And yet 436 B stays completely frozen. It is literally an ice cube on fire. The surface on Gliese 436 B stays at a constant temperature because it is so close to its star, and that temperature is a whopping 439 °C. Given that water boils at 100 °C, the presence of ice should be an impossibility. Except its not really ice, at least not in the classical sense. Its a phenomenon knows as hot ice or ice-ten. It would look much like the ice we have here on Earth, but if you were to and pick some up, you would need a new hand.
Let's assume there is a planet that has wildlife, vegetation, oxygen, and all of it is safe for humans. It's basically Earth 2.0.
The problem is, its 2, maybe 3 times the mass.
Would we even attempt permanent settlement there? How safe in the long term would all that extra weight be? Would we try to essentially adapt to it?
Let's assume there is a planet that has wildlife, vegetation, oxygen, and all of it is safe for humans. It's basically Earth 2.0.
The problem is, its 2, maybe 3 times the mass.
Would we even attempt permanent settlement there? How safe in the long term would all that extra weight be? Would we try to essentially adapt to it?
I could be wrong about this but just the fact that its 2 to 3x the mass doesn't mean gravity would be 2 to 3x as strong as Earth's. I believe speed of rotation and solidity of the core plays a factor as well. For example, I think you'd weigh less on Uranus than you would on Mercury.
I don't know exactly what you're trying to say here, reads a bit like a mess. You need mass and radius to calculate it. It's also possible to calculate it given density, apparently, but what you're saying is silly. Making Earth bigger wouldn't make the gravity 'weaker', the mass would still be the same, and if you would be the same distance from the center, the gravitational acceleration would be the same as it were now.Indeed. Planet's density is much more important for determining gravity.
Shrink Earth sufficiently and it becomes a black hole, make it bigger and gravity gets weaker.
Atmospheric pressure affects liveability as well, but i wonder if it can compensate for weaker or higher gravity (ie high g, less pressure or vice versa)?
I don't know exactly what you're trying to say here, reads a bit like a mess. You need mass and radius to calculate it. It's also possible to calculate it given density, apparently, but what you're saying is silly. Making Earth bigger wouldn't make the gravity 'weaker', the mass would still be the same, and if you would be the same distance from the center, the gravitational acceleration would be the same as it were now.
To calculate the surface gravity, check here. Acceleration = (Gravitational constant * Mass) / (radius^2).
Only because the surface is now further from the center. If you were to dig in, and be at the same distance from the center as we are now, the gravitational acceleration would be the same.Make Earth bigger, ie increase its radius (without changing mass, so density gets lower), that would reduce surface gravity, no?
If you also increased mass by right amount, gravity would stay same, no? Density... eh, I don't remember how to calculate sphere's density...
I could be wrong about this but just the fact that its 2 to 3x the mass doesn't mean gravity would be 2 to 3x as strong as Earth's. I believe speed of rotation and solidity of the core plays a factor as well. For example, I think you'd weigh less on Uranus than you would on Mercury.
Indeed. Planet's density is much more important for determining gravity.
Shrink Earth sufficiently and it becomes a black hole, make it bigger and gravity gets weaker.
Atmospheric pressure affects liveability as well, but i wonder if it can compensate for weaker or higher gravity (ie high g, less pressure or vice versa)?
EDIT: note: just my thoughts about this
Anyone spreading to stars likely won't have any internal dissent that manifests itself in war, for anyone having enough energy for interstellar travel* will have enough energy to decimate their planets, space colonies and whatever utterly.
In a war, both sides would control that and they'd destroy themselves most likely. If only one side controls such power, they win (assuming they are willing to destroy their opposition completly).
*Assuming they want to do that fast (travel times being decades, or centuries at most), which requires fusion rockets, nuclear pulse propulsion or other high-energy propulsion system. That said, ion thrusters require a lot of power, which doubles as power source for laser weapons...
Of course this also means they may well wipe out/contain anyone they find to make sure they don't have to fight later.
Or they're in constant state of war. Or perhaps they go trans-uh, transalien and inhabit computers and virtual realities (and war there).
Problem with extra-terrestial life is that anyone out there is likely to be much more primitive than us (apes), or much more advanced than us (angels).
Regardless, they're likely to have moral systems that are unlike ours. Systems which may have no issues with internal fighting. I'm no moral relativist when it comes to human cultures and morals but aliens? We can't say anything about them, for most likely they think utterly different from us, logic, emotions, morals, priorities, needs....
Which is why i think we need to be prepared for war once we venture to space (which is why internal conflict is useful, for it gives us experience, though i'm not sure the cost is really worth it...). Probably as aggressors, you don't think about enemy intent when planning, only about their capabilities. And if your (potential) enemy has capability to destroy you, you need to match that (mutually assured destruction), or wipe them out before they can do anything.
Some interesting points you made but let me ask you do you think its possible to evolve ..um passively? I mean do you think its possible for a species to evolve without any hostile tendencies like perhaps herbivores?
EDIT: Sorry for the stupid question
Astonishing footage of SpaceX Grasshopper rocket going up 250 meters and landing back:
https://www.youtube.com/watch?v=NoxiK7K28PU&feature=youtube_gdata_player
Astonishing footage of SpaceX Grasshopper rocket going up 250 meters and landing back:
https://www.youtube.com/watch?v=NoxiK7K28PU&feature=youtube_gdata_player
Damn Straight!
Astonishing footage of SpaceX Grasshopper rocket going up 250 meters and landing back:
https://www.youtube.com/watch?v=NoxiK7K28PU&feature=youtube_gdata_player
Astonishing footage of SpaceX Grasshopper rocket going up 250 meters and landing back:
https://www.youtube.com/watch?v=NoxiK7K28PU&feature=youtube_gdata_player
Astonishing footage of SpaceX Grasshopper rocket going up 250 meters and landing back:
https://www.youtube.com/watch?v=NoxiK7K28PU&feature=youtube_gdata_player
Astonishing footage of SpaceX Grasshopper rocket going up 250 meters and landing back:
https://www.youtube.com/watch?v=NoxiK7K28PU&feature=youtube_gdata_player
Astonishing footage of SpaceX Grasshopper rocket going up 250 meters and landing back:
https://www.youtube.com/watch?v=NoxiK7K28PU&feature=youtube_gdata_player
jett said:That's pretty interesting. They really need to find a more efficient way to defeat gravity, though...somehow.
Amazing images of the storm on Saturn at Bad Astronomy's site:
The raging eye of Saturn
The second wider view shot on the site....wow speechless
Since GAF loves Sagan, can we have a t-shirt of this in the t-shirt store?
Just saw this thread subscribed especially for the potential place for wallpapers and breaking news regarding space.
Does anyone here have some good arguments about why we should thrive to finance space travel?
Think you meant strive
You might want to make your question more specific. "Space travel" to me implies beyond low Earth orbit (i.e. to the Moon, Mars, asteriods, etc.)... Satellites, communication and GPS is covered by low Earth orbit, and I don't think there's much "striving" left to do or needed there.
You're seven years late to the party
Gemüsepizza;56412484 said:Not that much in cosmic standards. ^^
Gemüsepizza;56412484 said:Not that much in cosmic standards. ^^
I've always seen this thread and lurked around. Although I work at NASA, astronomy isn't my thing, but I still enjoy the finds.
Sure you work at Nasa. Show me the aliens.
meteor sighting in UK tonight
seen the post on reddit. nothing like the Russian one. BBC link
I've always seen this thread and lurked around. Although I work at NASA, astronomy isn't my thing, but I still enjoy the finds.
If you don't mind me asking, what do you do there?
Does anyone here have some good arguments about why we should strive to finance space travel?
For example: because we need satellites in this day and age for communications, GPS, ...
I need to convince some people.