Habitable planets easier to find than previously believed

[Bateluer]

http://www.theverge.com/2013/6/25/4462744/habitable-planets-more-common-certain-solar-systems

An international team of astronomers, led by the University of Göttingen's Guillem Anglada-Escudé, claims to have identified a certain type of star that may be circled by significantly more habitable planets than researchers generally expect to find. Such stars are smaller than our Sun, requiring that habitable planets orbit close to them because of their lower mass. That makes planets cluster together, allowing them to be more easily spotted now that researchers know to look for them. "Instead of observing 10 stars to look for a single potentially habitable planet, we now know we can look at just one star and find several of them," Rory Barnes, a member of the research team, explained in a statement.

The astronomers' findings revolve around the discovery of up to four additional habitable planets in a place where there were only believed to be two or three. The planets were found about 22 light years away from us in a solar system known as Gliese 667C. And while each is believed to be a habitable planet — a body that can support liquid water and contain an atmosphere — equally notable is how large many of them are: around half of the planets are believe to be up to 10 times as big as the Earth. The researchers have also postulated that these "super-Earths" may be more common than believed as well. Those discoveries will be published in next month's Astronomy & Astrophysics journal.

Neat stuff, even our tiny arm of the Milky Way is a huge place. Of course, there's still the minor problem of actually getting to these planets.

 

[SagaLore]

http://www.theverge.com/2013/6/25/4462744/habitable-planets-more-common-certain-solar-systems



Neat stuff, even our tiny arm of the Milky Way is a huge place. Of course, there's still the minor problem of actually getting to these planets.

Nah, that is going to be solved very soon:

forums.anandtech.com/showthread.php?t=2325868

 

[Ruptga]

Nah, that is going to be solved very soon:

forums.anandtech.com/showthread.php?t=2325868

404

Maybe you meant this one?

http://forums.anandtech.com/showthread.php?t=2327274

I dunno, it is somewhat interesting, but we still have yet to get our asses to Mars. The only way interstellar probing, let alone travel, is going to be possible in my lifetime is if I become immortal. Even if we do achieve immortality within 60-70 years, it will likely be another fifty before any real interstellar probes are launched, and another hundred before their test results reach home.

 

[Paratus]

As I've posted elsewhere we're actually working on it.

http://m.popsci.com/technology/article/2013-03/warp-factor

 

[Connoisseur]

There's also the small issue of these planets we're detected so far being several times larger... the gravity would be astronomical relative to our earth. I would love to see how we'd land and/or survive in such gravity and air pressure. In my mind, we need to not only find habitable zone planets, but also planets that are of similar size/mass. Unless we start bio-engineering humans to withstand the massive forces.

I feel like in some ways, all things being equal (including distance), it'd be easier to figure out how to survive and/or terraform dead planets such as mars and venus instead of looking for environmentally habitable worlds.

 

[Connoisseur]

As I've posted elsewhere we're actually working on it.

http://m.popsci.com/technology/article/2013-03/warp-factor

Just reading through the article, it seems that the "experiment" that they're working on defies any known laws of physics. Seems like wasting time rather than designing something that can actually get results.

 

[DrPizza]

There's also the small issue of these planets we're detected so far being several times larger... the gravity would be astronomical relative to our earth. I would love to see how we'd land and/or survive in such gravity and air pressure. In my mind, we need to not only find habitable zone planets, but also planets that are of similar size/mass. Unless we start bio-engineering humans to withstand the massive forces.

I feel like in some ways, all things being equal (including distance), it'd be easier to figure out how to survive and/or terraform dead planets such as mars and venus instead of looking for environmentally habitable worlds.

The gravity wouldn't necessarily be that huge. Multiplying the mass by 10 doesn't result in 10 times the gravity at the surface, unless the new planet is the same size. For instance, Jupiter is 317.8 times as massive as the Earth. But, at the surface, gravity is only 2.54 times that at the surface of the Earth.

And, air pressure is also somewhat independent. Counter-example: look at the air pressure at the surface of Venus. It only has 81% the mass of the Earth. But, the atmospheric pressure at the surface is 92 times higher.



edit: thinking out loud... gravity is proportional to m/r². m/v = density, so m/d = volume. radius is proportional to cubed root of volume, so radius is proportional to cubed root of (mass/density) So.... gravity is proportional to mass over (mass/density)^2/3. Let's multiply the mass by 10, and have 80% of the density... 10/(10/.8)^(2/3)...
10/(100/8)^(2/3) ... 10*(8/100)^(2/3) ... 20/100^(2/3) ... 20/ cubed root of 10,000 ... 2/cubed root of 10. Cubed root of 10 is a little more than 2, so.. holy shit, that can't be right. I need paper (or someone else to check this) I ended up with a less gravity under the condition that it had 80% the density.

edit edit: grabbed some paper and worked through this carelessly. If you have 10 times the mass, and the same density, you'll have the cubed root of 10 times as much gravity at the surface, so 2.15 times g at the surface. So, it's easy to conceive that with a lower density, you could have a corresponding larger radius, and thus less than twice as much gravity.

 

[xalos]

The gravity wouldn't necessarily be that huge. Multiplying the mass by 10 doesn't result in 10 times the gravity at the surface, unless the new planet is the same size. For instance, Jupiter is 317.8 times as massive as the Earth. But, at the surface, gravity is only 2.54 times that at the surface of the Earth.

And, air pressure is also somewhat independent. Counter-example: look at the air pressure at the surface of Venus. It only has 81% the mass of the Earth. But, the atmospheric pressure at the surface is 92 times higher.



edit: thinking out loud... gravity is proportional to m/r². m/v = density, so m/d = volume. radius is proportional to cubed root of volume, so radius is proportional to cubed root of (mass/density) So.... gravity is proportional to mass over (mass/density)^2/3. Let's multiply the mass by 10, and have 80% of the density... 10/(10/.8)^(2/3)...
10/(100/8)^(2/3) ... 10*(8/100)^(2/3) ... 20/100^(2/3) ... 20/ cubed root of 10,000 ... 2/cubed root of 10. Cubed root of 10 is a little more than 2, so.. holy shit, that can't be right. I need paper (or someone else to check this) I ended up with a less gravity under the condition that it had 80% the density.

edit edit: grabbed some paper and worked through this carelessly. If you have 10 times the mass, and the same density, you'll have the cubed root of 10 times as much gravity at the surface, so 2.15 times g at the surface. So, it's easy to conceive that with a lower density, you could have a corresponding larger radius, and thus less than twice as much gravity.

The r^2 isn't radius for gravitational force. It's the distance between the centers of the two objects. So, a planet that is 10x the size of the earth could have the same gravity as earth if it was the right distance from the star it was orbiting.

 

[Paratus]

Just reading through the article, it seems that the "experiment" that they're working on defies any known laws of physics. Seems like wasting time rather than designing something that can actually get results.

Well I happen to work at JSC and have a friend on the project. These guys are doing basic research. The basic idea behind "warp drive" does not violate relativity. The warping they're looking for has been observed indirectly in nature. Normal curving of space time is done by gravity. The more exotic warping happend during the inflationary expansion phase of the universe right after the Big Bang.

The research they are doing is basically to see whether we can warp space to the point it's measurable. It will work or it won't, but its based on observed phenomenon and proven theory.

White-Juday Warp Field Interferometer

The other work going on is a propellant-less thruster that uses quantum vacuum particles as the working fluid.

Quantum Vacuum Plasma Thruster

A Q-thruster will utilize quantum vacuum fluctuations as its propellant. The quantum mechanical Casimir effect has demonstrated that quantum vacuum fluctuations do exist.[1]

A Q-thruster then uses the same principles and equations of motion that a conventional plasma thruster would use, namely magnetohydrodynamics (MHD), to predict propellant behavior. The virtual plasma is exposed to a crossed E-field and B-field, inducing a drift of the entire plasma in the E×B direction, which is orthogonal to the applied fields. The difference arises in the fact that a Q-thruster uses quantum vacuum fluctuations as its propellant, eliminating the need to carry any. This suggests much higher specific impulses are available for quantum vacuum plasma thrusters that will be limited only by their power supply’s energy storage densities. Test results have suggested thrust levels of between 1000–4000 μN, specific force performance of 0.1N/kW, and an equivalent specific impulse of ~1x1012 seconds.[2][3]

 

[silverpig]

The r^2 isn't radius for gravitational force. It's the distance between the centers of the two objects. So, a planet that is 10x the size of the earth could have the same gravity as earth if it was the right distance from the star it was orbiting.

He's talking surface gravity. r = r in that case

 

[DrPizza]

He's talking surface gravity. r = r in that case

Well, he's got me on a technicality. I guess if I was standing at the surface, my center of mass is almost, but not quite, one meter above the surface.

 

[Paratus]

It seems likely to me that in the next 30 years we may find an actual Earth like planet. With ability to use the incoming light to determine the chemical make up of the atmosphere we may actually be able to see life before SETI hears from it.

 

[OverVolt]

Is that why in sci-fi movies the aliens always have more stuff? They get a bigger planet? No fair :awe:

 

[xalos]

He's talking surface gravity. r = r in that case

Yeah, I had a knee jerk reaction. When I tutored physics I had to point out that difference all the time...lol

 

[stormkroe]

Well, he's got me on a technicality. I guess if I was standing at the surface, my center of mass is almost, but not quite, one meter above the surface.

And changing the older and fatter you get

The main problem I see with these POTENTIALLY habitable planets is that I haven't ever seen a model that compensates for gravities varying from earth's jackpot spec. Just enough for water to escape into space, any weaker and we'd dry out, any stronger and we'd greenhouse into death by heat. I'd love to see postulating on this issue, especially peer reviewed theories.

 

[Connoisseur]

edit edit: grabbed some paper and worked through this carelessly. If you have 10 times the mass, and the same density, you'll have the cubed root of 10 times as much gravity at the surface, so 2.15 times g at the surface. So, it's easy to conceive that with a lower density, you could have a corresponding larger radius, and thus less than twice as much gravity.

Right you are and I stand corrected. I forgot my basic physics. Regardless, even 2x earth's gravity is fairly intense in my mind. I'm a 190 pound person. I'd imagine having to carry around a bulk of 380 lbs all the time. I don't think the human body is built for it. We'd have to physically shrink considerably to allow our bones, muscles and circulatory system to have a feasible chance of working. Not to mention the amount of energy required to land and take off safely. I'm not saying it's not doable but it's definitely a big challenge that no one seems to mention. It's like "hey once we get there, we're set!"

 

[Ruptga]

Right you are and I stand corrected. I forgot my basic physics. Regardless, even 2x earth's gravity is fairly intense in my mind. I'm a 190 pound person. I'd imagine having to carry around a bulk of 380 lbs all the time. I don't think the human body is built for it. We'd have to physically shrink considerably to allow our bones, muscles and circulatory system to have a feasible chance of working. Not to mention the amount of energy required to land and take off safely. I'm not saying it's not doable but it's definitely a big challenge that no one seems to mention. It's like "hey once we get there, we're set!"

True, but it really comes down to the specifics. For example, if the air is more dense controlled flight may not be all that much harder to manage. Increased air density would also supply more oxygen, compensating somewhat for the harsher gravity. With some bioengineering and/or cybernetics I have no doubt that it is possible, in time, for us to survive on another (carefully picked) planet.

 

[DrPizza]

I thought more about the pressure too. Scuba divers don't seem to have much trouble breathing in pressurized air - the air they're breathing matches the pressure of the water they're in.

 

[Connoisseur]

Yeah but their overall activity level is a lot lower isn't it? The water is supporting their body weight. Imagine your body going through both the effort of breathing high pressure air and still having energy to carry around your body weight.

 

[ImpulsE69]

No physics expert so correct me if I'm way off base, but doesn't rotational speed also have an impact on all of this?

Without knowing how life sparked, it makes you wonder if there ARE any earthlike planets out there. We are a product of our environment and that environment formed under precise conditions (that we aren't really sure of). Would one assume then that if there is a planet out there that is similar to earth, then it would have to be approximately the same age and should by that reason have life already? Obviously there is so much more to it than just size, distance from sun, etc.

Actually thinking about that the above is obviously wrong since there could be worlds that were similar to earth millions of years ago, but of course have long passed that phase of life.

 

[phucheneh]

You guys are apparently thinking about this as planets for us to colonize. Because Firefly or something.

What I see as more relevant is simply that we're getting better at finding places where other life can exist. Since it doesn't have to be us, you can throw out stuff like atmospheric pressure and gravity. The planet basically just needs...an atmosphere. Of something. The presence of liquid...something. We have plenty of funky shit on Earth that demonstrates that simple life can find ways to live under strange circumstances.

Maybe there are crazy space-mermen swimming around in the methane lakes and breathing nitrogen on Saturn's moon, Titan. Or just some kinda weird bacteria. But SOMETHING is still a huge leap. And now we're coming up with better places to look.

 

[ImpulsE69]

You guys are apparently thinking about this as planets for us to colonize. Because Firefly or something.

What I see as more relevant is simply that we're getting better at finding places where other life can exist. Since it doesn't have to be us, you can throw out stuff like atmospheric pressure and gravity. The planet basically just needs...an atmosphere. Of something. The presence of liquid...something. We have plenty of funky shit on Earth that demonstrates that simple life can find ways to live under strange circumstances.

Maybe there are crazy space-mermen swimming around in the methane lakes and breathing nitrogen on Saturn's moon, Titan. Or just some kinda weird bacteria. But SOMETHING is still a huge leap. And now we're coming up with better places to look.

Yea you worded it better. That is kind of what I was getting at. We formed under our planets conditions. If there was life elsewhere, it would be used to it's conditions. They are just searching for things similar to ours as a basis to look.

 

[phucheneh]

No physics expert so correct me if I'm way off base, but doesn't rotational speed also have an impact on all of this?

Without knowing how life sparked, it makes you wonder if there ARE any earthlike planets out there. We are a product of our environment and that environment formed under precise conditions (that we aren't really sure of). Would one assume then that if there is a planet out there that is similar to earth, then it would have to be approximately the same age and should by that reason have life already? Obviously there is so much more to it than just size, distance from sun, etc.

I don't think anyone is sure about the likelihood of things unfolding like they did on Earth. But one would think that it SHOULD have happened somewhere else by now. And they may all be dead. The key in actually communicating with intelligent life would be in actually finding something that fits with our timeline; rather than just happening upon some burned-out planets where maybe a society thrived a billion years ago.

 

[phucheneh]

Keep in mind that 'earth-like' doesn't mean water and vegetation and stuff. They're just looking for planets with characteristics that kind of make sense. Titan is an example...and there's another promising moon that I can't recall the name of...but basically, it just needs to be chunk of rock with a substantial atmosphere, some kind of liquid, and temperatures that are not absolutely retarded. And right now, they're trying to figure what areas they need to look in to find these planets or moons.

 

[JTsyo]

No physics expert so correct me if I'm way off base, but doesn't rotational speed also have an impact on all of this?

Without knowing how life sparked, it makes you wonder if there ARE any earthlike planets out there. We are a product of our environment and that environment formed under precise conditions (that we aren't really sure of). Would one assume then that if there is a planet out there that is similar to earth, then it would have to be approximately the same age and should by that reason have life already? Obviously there is so much more to it than just size, distance from sun, etc.

Actually thinking about that the above is obviously wrong since there could be worlds that were similar to earth millions of years ago, but of course have long passed that phase of life.

Don't forget, Earth has supported life for millions of years. heck you go back to just single cell creatures it would be 3 billion years ago. It's finding intelligent life that would have a much narrower window. Even if we just find the remains of a dead planet, at least it would be proof that there is life elsewhere. So far we have a sample of one but we could see that life arose independently on two worlds, that opens up many possibilities.

As for settling other worlds, we'll never be able to just take ourselves and settle another planet. Either we would have to be modified or the planet would. Our ability to reach these far flung worlds is so far in the future than we'll have time to "tech up".