Super-Earth Discovered In Star's Habitable Zone

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Super-Earth Discovered In Star's Habitable Zone

Posted by samzenpus on Wednesday November 7, 2012 @03:33PM from the big-house dept.

astroengine writes "The family of planets circling a relatively close dwarf star has grown to six, including a potential rocky world at least seven times more massive than Earth that is properly located for liquid water to exist on its surface, a condition believed to be necessary for life. Scientists added three new planets to three discovered in 2008 orbiting an orange star called HD 40307, which is roughly three-quarters as massive as the sun and located about 42 light-years away in the constellation Pictor. Of particular interest is the outermost planet, which is believed to fly around its parent star over 320 days, a distance that places it within HD 40307's so-called "habitable zone.""

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Fermi's p by harvey+the+nerd · 2012-11-07 15:40 · Score: 4, Funny

seven times more massive than Earth...
so much for their early space program
1. Re:Fermi's p by NEDHead · 2012-11-07 15:48 · Score: 4, Informative
  
  Depends on the diameter and the rate of rotation.
2. Re:Fermi's p by macraig · 2012-11-07 15:53 · Score: 4, Insightful
  
  So they'll leapfrog straight to quantum teleportation, then?
3. Re:Fermi's p by rossdee · 2012-11-07 15:54 · Score: 4, Interesting
  
  Just as well, because if they ever did get off their planet they would be able to beat us.
  (their ships would out maneuver ours , they would have faster reflexes, and we wouldn't have a chance in hand to claw combat
4. Re:Fermi's p by feedayeen · 2012-11-07 15:54 · Score: 5, Informative
  
  seven times more massive than Earth...
  so much for their early space program
  Assuming 2 planets have equal densities, Mass increases proportional to R^3, but gravity is proportional to the inverse squared of the distance.... As a result, surface gravity increases only linearly with the radius.... in this case, the planet would have 1.9 times the radius of the Earth if it's the same density.
  Earth has a very high density actually at 5.5g/cm3, it's actually the densest planetary object in our solar system. Most terrestrial objects are closer to 2 and the larger ones tend to be 3. It is entirely possible that it'll have a comparable surface gravity.
5. Re:Fermi's p by Aighearach · 2012-11-07 16:06 · Score: 2
  
  seven times more massive than Earth...
  so much for their early space program
  And the green alien sex.
6. Re:Fermi's p by slashmydots · 2012-11-07 16:09 · Score: 1
  
  Space program? So much for amoebas having the energy to move around.
7. Re:Fermi's p by wierd_w · 2012-11-07 17:37 · Score: 2
  
  Assuming they use extensible appendages for locomotion at all.
  At that level of local gravity, they are more likely to be something like a gastropod, or aquatic.
  pumping blood under 7 Gs is something human hearts require a pressure suit for! Any large bodied creatures from that planet would have to have a very different anatomic makeup from ours.
8. Re:Fermi's p by Sperbels · 2012-11-07 17:38 · Score: 4, Funny
  
  Just as well, because if they ever did get off their planet they would be able to beat us. (their ships would out maneuver ours , they would have faster reflexes, and we wouldn't have a chance in hand to claw combat
  Would they? Maybe their biochemistry makes it more efficient for them to have extremely slow reflexes. Maybe their movements would be as fast as grass growing. We could round up their entire invasion force and give them all anal probes and alien autopsies before they even knew what happened.
9. Re:Fermi's p by Endovior · 2012-11-07 18:30 · Score: 3, Insightful
  
  Good math, but you're ignoring the effect of mass on density. Earth is more dense than (for example) Mars because its greater mass results in more gravitational pressure, thus compressing its core, and increasing the density. There are limits, of course, and composition really does play a much bigger role than mass... hence why Mercury is the second densest planet in our system, despite being significantly less massive, and why gas giants have much lower densities, despite being vastly more massive. Even so, given that we don't know anything about the composition of this planet, odds are that since it's more massive than Earth, it'll have a higher density. How much higher would be pure speculation, of course, but because of that factor, I'd bet on a radius less than 1.9 Earths, and a gravity of more than 2 G.
10. Re:Fermi's p by symbolset · 2012-11-07 18:49 · Score: 2
  
  A planet like that almost certainly has a moon of the correct size and composition. When we get to the stars we will find that almost all have homes for Men.
  
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  Help stamp out iliturcy.
11. Re:Fermi's p by roc97007 · 2012-11-07 19:06 · Score: 1
  
  Just as well, because if they ever did get off their planet they would be able to beat us.
  (their ships would out maneuver ours , they would have faster reflexes, and we wouldn't have a chance in hand to claw combat
  "But they die young, of heart problems"...
  
  --
  Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
12. Re:Fermi's p by Anonymous Coward · 2012-11-07 19:43 · Score: 0
  
  That's no moon...
13. Re:Fermi's p by Joshua+Fan · 2012-11-07 20:50 · Score: 1
  
  ...1.9 times the radius of the Earth...
  I believe a planet with 7.1 times the mass of Earth, assuming the same density, would only have 1.1923 times the radius of Earth. Check your math.
14. Re:Fermi's p by Jane+Q.+Public · 2012-11-07 21:08 · Score: 2
  
  Not so much. They say it's rocky and roughly liquid-water distance so it's probably close to Earth density, which limits the diameter. Spin rate might affect the perceived gravity but because of other factors is probably not very much of an issue.
  
  Most likely, surface gravity would be roughly 3 times Earth gravity.
15. Re:Fermi's p by Anonymous Coward · 2012-11-07 21:10 · Score: -1
  
  Anal probes ? Interesting. Rule 34, anyone? http://rule34.paheal.net/
16. Re:Fermi's p by Bill+Currie · 2012-11-07 21:14 · Score: 5, Informative
  
  No, his math is quite correct: M=d*4*pi*r^3, so M(p)/M(e) = (d*4*pi*r(p)^3)/(d*4*pi*r(e)) which simplifies to r(p)^3/r(e)^3, or (r(p)/r(e))^3, thus the ratio is the cube-root of 7: 1.913 (or 7.1: 1.922). Still, 2G would be a cow for us.
  
  --
  Bill - aka taniwha
  --
  Leave others their otherness. -- Aratak
17. Re:Fermi's p by Chrisq · 2012-11-07 22:01 · Score: 1
  
  seven times more massive than Earth...
  so much for their early space program
  And the green alien sex.
  It might be OK still as long as they aren't on top
18. Re:Fermi's p by Anonymous Coward · 2012-11-07 22:11 · Score: 5, Funny
  
  We could round up their entire invasion force and give them all anal probes and alien autopsies before they even knew what happened.
  I find your ideas intriguing and would like to subscribe to your newsletter.
19. Re:Fermi's p by Anonymous Coward · 2012-11-07 22:38 · Score: 0
  
  You mean nuke to death beam combat?
20. Re:Fermi's p by Electricity+Likes+Me · 2012-11-07 22:53 · Score: 1
  
  Not really - the continents basically "float" on the mantle, so depending how hot it's core is that would affect how much pressure it exerted on the crust (and thus how wide it could be).
21. Re:Fermi's p by Spottywot · 2012-11-07 23:13 · Score: 2
  
  seven times more massive than Earth... so much for their early space program
  Maybe, or maybe they just develop different tech, space elevator maybe?
  
  --
  In a cybernetic fit of rage she pissed off to another age...
22. Re:Fermi's p by Turminder+Xuss · 2012-11-08 00:20 · Score: 1
  
  This is why we should all be training with weights in a knapsack.
  
  --
  You seem to regard science as some kind of dodge... or hustle.
23. Re:Fermi's p by RaceProUK · 2012-11-08 00:28 · Score: 1
  
  ...it's a co-orbital asteroid :)
  
  --
  No colour or religion ever stopped the bullet from a gun
24. Re:Fermi's p by Talderas · 2012-11-08 00:34 · Score: 1
  
  They could be Elcor.
  
  --
  "Lack of speed can be overcome. In the worst case by patience." --Znork
25. Re:Fermi's p by tgd · 2012-11-08 01:02 · Score: 1
  
  seven times more massive than Earth...
  so much for their early space program
  Unless its covered in a form of plant life that absorbs, refines and aggregates Uranium, eventually ending up in small thermonuclear blasts used to spread their spores in a more effective way in the high gravity. Then the inhabitants can just collect up their nukkel fruits, and make their own Orion-type engines to get off the planet.
  It'd be a real blast.
26. Re:Fermi's p by tgd · 2012-11-08 01:04 · Score: 4, Funny
  
  Just as well, because if they ever did get off their planet they would be able to beat us.
  (their ships would out maneuver ours , they would have faster reflexes, and we wouldn't have a chance in hand to claw combat
  And worst of all, their muscles are probably so dense, no amount of slow roasting will bring out any real flavor.
27. Re:Fermi's p by Anonymous Coward · 2012-11-08 01:10 · Score: 0
  
  Good math, but you're ignoring the effect of mass on density. Earth is more dense than (for example) Mars because its greater mass results in more gravitational pressure, thus compressing its core, and increasing the density. There are limits, of course, and composition really does play a much bigger role than mass... hence why Mercury is the second densest planet in our system, despite being significantly less massive, and why gas giants have much lower densities, despite being vastly more massive. Even so, given that we don't know anything about the composition of this planet, odds are that since it's more massive than Earth, it'll have a higher density. How much higher would be pure speculation, of course, but because of that factor, I'd bet on a radius less than 1.9 Earths, and a gravity of more than 2 G.
  WHAT?!?!?!
  You got +5 for THAT!??!?!
  WTF?
  Come on, folks.
  Solids and liquids are not significantly compressible.
28. Re:Fermi's p by Anonymous Coward · 2012-11-08 01:18 · Score: 1
  
  Earth is denser than Mercury despite being made of lighter materials.
29. Re:Fermi's p by petermgreen · 2012-11-08 01:37 · Score: 1
  
  Afaict there are two big problems with the concept of the space elevator.
  One is materials, you need a material that is strong enough to support it's own weight without the CSA ratio* becoming insane.
  The other is how do you put the thing into place? Afaict the normal technique for reaching high orbits is to gradually increase the orbit but that won't work for a craft towing a space elevator cable (you'd wrap the cable round the planet) so you would need a rocket that could go "straight up" which aiui is much harder to build.
  So space elevators if possible at all are something that comes AFTER you have a rocket based space program and want to expand it.
  
  --
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30. Re:Fermi's p by dkf · 2012-11-08 01:56 · Score: 5, Informative
  
  Solids and liquids are not significantly compressible.
  While you're correct that they're a lot less compressible than a gas, you most certainly can still compress solids and liquids if you press hard enough. There's a lot of pressure inside the core of a planet...
  
  --
  "Little does he know, but there is no 'I' in 'Idiot'!"
31. Re:Fermi's p by JCCyC · 2012-11-08 02:02 · Score: 1
  
  Getting up in the morning must be a bitch.
32. Re:Fermi's p by NEDHead · 2012-11-08 02:24 · Score: 4, Informative
  
  Your math is a little off. If the density were the same as Earth's, the diameter would be proportional to the cube root of the mass ratios, or slightly less than 2 times that of Earth. The surface gravity is proportional to mass (7x) and inversely so to the square of the radius (~1/4) so 7/4 is about 1.75 surface gravity compared to Earth. If there were a comparable 'day' length, then the velocity at the equator would be about 2x that of Earth. An extra 1000 mph liftoff boost vs 1.75 local g, not so hard to overcome.
  And since we know nothing about the planet other than the mass, this is all silly speculation.
33. Re:Fermi's p by Anonymous Coward · 2012-11-08 03:15 · Score: 0
  
  Solids and liquids are not significantly compressible.
  Data appears to contradict you:
  coal : 0.64 g/cc (http://www.asiinstr.com/technical/Material_Bulk_Density_Chart_C.htm)
  diamond: 3.5–3.53 g/cc (https://en.wikipedia.org/wiki/Diamond)
  Yes, it is much HARDER to compress them, but they sure do compress, under planetary levels of pressure.
34. Re:Fermi's p by Anonymous Coward · 2012-11-08 03:16 · Score: 0
  
  Your math isn't accurate either. Assuming constant density, mass is proportional to radius cubed. Since gravitation is proportional to mass over radius squared, this means the gravitation on the surface is proportional to the radius, that is, proportional to the third root of the mass. The third root of 7 is approximately 1.9.
  Of course, real materials are not completely incompressible, and seven times the mass means higher pressure, and therefore higher density, assuming the same material composition. Thus I guess a factor of 2 would be realistic.
  Of course, I completely agree with your last sentence.
35. Re:Fermi's p by Spottywot · 2012-11-08 03:22 · Score: 1
  
  Good points made, but the OPs point still holds. A rocket based space program would be significantly more resource hungry/expensive. I agree that a rocket would be necessary to install the elevator, but done right it could just be one rocket, with all subsequent payloads delivered by the elevator itself.
  It occurs to me that a race forced to make this their first step into space would have a distinct advantage when designing and building both their stellar and interstellar craft, in that they wouldn't be as space or mass constrained in their designs. By taking the harder first step, it may make subsequent steps easier
  
  --
  In a cybernetic fit of rage she pissed off to another age...
36. Re:Fermi's p by Anonymous Coward · 2012-11-08 03:25 · Score: 0
  
  What is a ratio*, and how does it differ from a normal ratio?
37. Re:Fermi's p by canadiannomad · 2012-11-08 03:27 · Score: 1
  
  Thanks Sheldon....
  
  --
  Hmm, the humour and sarcasm seem to have been be lost on you.
38. Re:Fermi's p by rubycodez · 2012-11-08 03:34 · Score: 1
  
  One word: Pâté
39. Re:Fermi's p by rubycodez · 2012-11-08 03:37 · Score: 1
  
  stick your finger into the little brown star on its end and find out
40. Re:Fermi's p by X0563511 · 2012-11-08 04:14 · Score: 1
  
  Not necessarily. The things they could get into orbit would be smaller (because of that dang TWR) - though what they learn in getting it up there might exceed us, it would take them more effort to do something useful with it.
  
  --
  For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
41. Re:Fermi's p by lgw · 2012-11-08 04:15 · Score: 1
  
  Simple rule for SciFi RPG design: surface gravity is proportional to density times diameter. Easy to remember as the D&D rule.
  
  --
  Socialism: a lie told by totalitarians and believed by fools.
42. Re:Fermi's p by CrimsonAvenger · 2012-11-08 04:16 · Score: 1
  
  Your math is a little off. If the density were the same as Earth's, the diameter would be proportional to the cube root of the mass ratios, or slightly less than 2 times that of Earth. The surface gravity is proportional to mass (7x) and inversely so to the square of the radius (~1/4) so 7/4 is about 1.75 surface gravity compared to Earth. If there were a comparable 'day' length, then the velocity at the equator would be about 2x that of Earth. An extra 1000 mph liftoff boost vs 1.75 local g, not so hard to overcome.
  So is your's.
  Basic conditions you assume are reasonable (I get 1.9g, not 1.75), even with the extra equatorial rotation, still leaves you with 14 km/s+ deltaV to put something into orbit.
  which is rather more than Saturn V had to use to put Apollo into TLI (which was in the neighborhood of 12.5 km/s total).
  The extra deltaV required would increase liftoff mass by a third or more (depending in Isp used) - a rocket that big for your first attempt into orbit would be...problematic at best.
  Not impossible, mind you, but not something you'll consider without very good reason....
  
  --
  
  "I do not agree with what you say, but I will defend to the death your right to say it"
43. Re:Fermi's p by X0563511 · 2012-11-08 04:17 · Score: 1
  
  I'm pretty sure that won't matter. Such a small (relatively) change of gravity really isn't going to matter for things at that scale.
  
  --
  For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
44. Re:Fermi's p by mcgrew · 2012-11-08 04:19 · Score: 1
  
  You forget one salient point: they're only ten inches tall.
  
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  Free Martian Whores!
45. Re:Fermi's p by lgw · 2012-11-08 04:28 · Score: 1
  
  Actually, the big problem with a space elevator is that it will begin swinging uncontrollably if it lifts significant mass. At least for the Earth, getting into high orbit is about half overcoming grativational potential, and about half lateral acceleration. The elevator acts like a pendulum, but not an ideal frshman physics one, as the lateral force is applied gradually along it's length and the cable isn't rigid (and the orbital mechanics aren't quite the same as a pendulum). Each load you lifted would inject more energy into the systems, and in a chaotic way, with no obvious safe way to shed that energy.
  
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  Socialism: a lie told by totalitarians and believed by fools.
46. Re:Fermi's p by SleazyRidr · 2012-11-08 04:34 · Score: 1
  
  Because of course, high school science classes are not simplified in any way, they represent the truth exactly. I'm assuming the +5 came from the people who thought they were continuing their education by going to university, but really were just getting told lies by professors who wanted to make people believe them so they'd buy their books.
  
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  Is 1563649 a prime number?
47. Re:Fermi's p by feedayeen · 2012-11-08 04:37 · Score: 1
  
  Very true, there are other factors which may be contributing to our density like our lunar impactor which would have ejected lighter elements easier our our position in the accretion disk which would have provided us with supply of heavier raw elements. We also suspect that there's an upper limit for gas planets' volume based on gravitational collapse due to adding new material, one would expect a terrestrial analogue.
48. Re:Fermi's p by feedayeen · 2012-11-08 04:41 · Score: 1
  
  They're used to the gravity, you're not. They should be quite athletic by our standards and able to go all night, while you'd be wheezing just leaning against a poll.
49. Re:Fermi's p by Trilkk · 2012-11-08 05:21 · Score: 1
  
  The surface gravity is proportional to mass (7x) and inversely so to the square of the radius (~1/4) so 7/4 is about 1.75 surface gravity compared to Earth.
  That's actually rather close. Here's a handy graph for demonstration purposes.
50. Re:Fermi's p by Anonymous Coward · 2012-11-08 05:29 · Score: -1
  
  You are a fucking nigger.
51. Re:Fermi's p by jdray · 2012-11-08 05:46 · Score: 1
  
  I think you mean "pole". Election day is over, at least here.
  
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  The Spoon
  Updated 6/28/2011
52. Re:Fermi's p by Gilmoure · 2012-11-08 05:50 · Score: 1
  
  We're already doing this in publics schools.
  
  --
  I drank what? -- Socrates
53. Re:Fermi's p by Gilmoure · 2012-11-08 05:59 · Score: 1
  
  In west Texas, they know how to bbq a tough brisket until it melts in your mouth. Just sayin.
  
  --
  I drank what? -- Socrates
54. Re:Fermi's p by tgd · 2012-11-08 06:51 · Score: 1
  
  In west Texas, they know how to bbq a tough brisket until it melts in your mouth. Just sayin.
  Of course, in West Texas, they don't really believe in science, so we may have a bit of an impasse.
55. Re:Fermi's p by martinux · 2012-11-08 07:47 · Score: 1
  
  No, his math is quite correct: M=d*4*pi*r^3, so M(p)/M(e) = (d*4*pi*r(p)^3)/(d*4*pi*r(e)) which simplifies to r(p)^3/r(e)^3, or (r(p)/r(e))^3, thus the ratio is the cube-root of 7: 1.913 (or 7.1: 1.922). Still, 2G would be a cow for us.
  Hmmm, 3 digit ID and a comprehensive answer... sometimes correlation does imply causation!
56. Re:Fermi's p by TheTurtlesMoves · 2012-11-08 08:54 · Score: 1
  
  Actually, the big problem with a space elevator is that it will begin swinging uncontrollably if it lifts significant mass.
  
  It is easy to show this is not true. The Tension is the cable is so massive the lateral forces from acceleration is more or less insignificant with tiny deflections only. You can even model the traveling waves these set up. Its not really a hard problem to deal with.
  
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  The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
57. Re:Fermi's p by Jane+Q.+Public · 2012-11-08 10:14 · Score: 1
  
  I used the formula from Wikipedia. I'll stick with that, thanks very much.
58. Re:Fermi's p by Jane+Q.+Public · 2012-11-08 10:40 · Score: 1
  
  As mentioned above, I used Wikipedia's formula and a rough guesstimate of the radius (which might have been off). But they give the example of Gliese, which is 5 x Earth mass and has a surface gravity of about 2.2 times Earth. So I doubt very much that 7 x Earth mass, at the same density, would be less than 2 x Earth gravity.
59. Re:Fermi's p by lgw · 2012-11-08 12:35 · Score: 1
  
  The tension in the cable makes no difference at all to the total energy put into the system, only in the form it takes - vibration of the cable, or motion of the counterweight. Unless you have some way to shed this energy (such as the heat from friction), it just keeps accumulating. And the tension on the cable depends on the orbital mechanics: when the counterweight takes an eliptical orbit, things start to get ugly.
  Conversation of angular momentum means the counterweight must "swing back" when a load is lifted. Like a pendulum, it will swing forward (but it's not a freshman physics pendulum, it's a chaotic system). If you just keep adding energy to that system it will get out of control, and we'll be lucky to live through it. Energy and angular momentum will both be conserved - and there's no obvious way to keep both under control.
  
  --
  Socialism: a lie told by totalitarians and believed by fools.
60. Re:Fermi's p by Lanteran · 2012-11-08 12:36 · Score: 1
  
  For the last time, quantum teleportation has nothing to do with moving things or people around instantly- obligatory xkcd. Most likely thing is that they use a project orion style system for launch- only realistic system I can think of to escape from a world with 300% earth gravity.
  
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61. Re:Fermi's p by macraig · 2012-11-08 12:52 · Score: 1
  
  I said that instead of "teleporters" because I knew it would upset a physicist somewhere. :-)
62. Re:Fermi's p by Anonymous Coward · 2012-11-08 15:37 · Score: 0
  
  Wikipedia's formula? Constant density simplifies the problem as many have helpfully described above, such that a planet with 7x Earth's mass really would have ~1.9x Earth's gravity. Since Gliese 581 c is made of real matter which can be compressed, its gravity can be higher than the constant density approximation.
63. Re:Fermi's p by RockDoctor · 2012-11-10 09:20 · Score: 1
  
  The bit about assuming the same density is the killer. The pressure deep in the Earth is sufficiently high that the mineralogy at depth is more dense than the mineralogy that is stable at the surface. If we *knew* what the mineralogy at depth was (we don't) and if we knew the equation of state for those minerals, at those pressures and temperatures, for exactly those compositions, then we could calculate the density at each pressure, and thus the exact relationship between mass and radius.
  What we can measure, on Earth, is the velocity of compressional and shear sound waves (seismic waves) from point to point across the surface. There are still significant arguments about the composition of the Earth's core, to several percent of components. The core is too light to be simple nickel-iron, but does it have several percent of sulphur, or oxygen. Or potassium (put that in your core and smoke your primordial versus radiogenic heat models)? All would work, closely enough to fit the measurements.
  At this range, with this lack of precision of analysis, debates over the surface gravity are really likely to affect the number of angels you can fit per pinhead dance floor.
  
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64. Re:Fermi's p by Anonymous Coward · 2012-11-10 17:11 · Score: 0
  
  those religious physicist and their standard model belief system
65. Re:Fermi's p by TheTurtlesMoves · 2012-11-14 00:12 · Score: 1
  
  I know my physics. The angular momentum is transferred to/from the earth when things go up/down. This was thought about way back when these things where proposed. Really its not even hard to model, there is even the odd analysis floating around the net. You don't need much damping either to make the system stable. Finding a cable that is strong enough is the hard part and remains the hard part.
  
  --
  The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
Apostrophe! by Dan+East · 2012-11-07 15:47 · Score: 2, Insightful

Star's, not stars', unless the planet is orbiting more than one star at a time. Didn't we just talk about apostrophe abuse in another Slashdot headline a couple days ago?

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1. Re:Apostrophe! by Crypto+Gnome · 2012-11-07 15:54 · Score: 2, Informative
  
  Star's, not stars', unless the planet is orbiting more than one star at a time. Didn't we just talk about apostrophe abuse in another Slashdot headline a couple days ago?
  No, I'm pretty sure it was Child Abuse.
  
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2. Re:Apostrophe! by Tukz · 2012-11-07 20:51 · Score: 4, Funny
  
  Potato, tomato.
  
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3. Re:Apostrophe! by Taibhsear · 2012-11-08 02:19 · Score: 1
  
  tldr's
too heavy by Anonymous Coward · 2012-11-07 15:48 · Score: -1

at 7 earth masses the surface gravity won't allow the lightest gasses to escape the atmosphere, so a Venus like planet is the expected model
1. Re:too heavy by MyLongNickName · 2012-11-07 15:50 · Score: 5, Interesting
  
  Earth masses is not the same as surface gravity. Assuming a similar density, this planet would have roughly twice the gravity as Earth.
  
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2. Re:too heavy by Anonymous Coward · 2012-11-07 16:17 · Score: 0
  
  no escape velocity, still traps all the lighter gasses and ruins the surface environment
3. Re:too heavy by Merls+the+Sneaky · 2012-11-07 17:09 · Score: 1
  
  That is also assuming it has a magnetic field like earth and isn't bombarded by the solar (or whatever you would call the charged particles coming off an alien star) wind. There is much more that could be at play then just gravity and escape velocities.
4. Re:too heavy by Endovior · 2012-11-07 17:59 · Score: 1
  
  The article suggests that it actually gets less radiation than Earth does, so that sort of bombardment probably isn't an issue. That said, the lack of radiation could very well make advanced life unlikely, given the effects it'd have on mutation rate.
5. Re:too heavy by symbolset · 2012-11-07 18:54 · Score: 1
  
  Tidal forces would cause an Earth-sized moon to cool more slowly, improving stratification of the molten iron core. This improves the strength of the moon's magnetosphere. Radiation is probably fine.
  
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6. Re:too heavy by Anonymous Coward · 2012-11-07 22:02 · Score: 0
  
  That said, the lack of radiation could very well make advanced life unlikely, given the effects it'd have on mutation rate.
  The effects of radiation on genetic mutation are largely unknown. We have (in fairly recent years) discovered that genetic mutation can and does occur from environmental factors other than radiation. It's a huge unknown, so to be blunt it's equally likely that the reduced radiation could actually lead to more stable mutations and an overall increased evolution rate.
7. Re:too heavy by Electricity+Likes+Me · 2012-11-07 22:58 · Score: 2
  
  That said, the lack of radiation could very well make advanced life unlikely, given the effects it'd have on mutation rate.
  The effects of radiation on genetic mutation are largely unknown. We have (in fairly recent years) discovered that genetic mutation can and does occur from environmental factors other than radiation. It's a huge unknown, so to be blunt it's equally likely that the reduced radiation could actually lead to more stable mutations and an overall increased evolution rate.
  I'd like to be even more specific: you don't need radiation for genetic mutation to occur. Standard DNA polymerases make mistakes all the time without any outside forces beyond thermodynamics, and simple viruses like Ebola tend to have very poorly performing RNA polymerases that make a lot of mistakes because it's advantageous to their survival to do so.
  Conversely, bacteria that live in fuel rod settling pools take the opposite approach - they "staple" their DNA together with a high GC content to improve radiation resistance. There's such a diverse range of factors at play that it's ridiculous to suggest "radiation" would give us any information about whether a place could have advanced life.
8. Re:too heavy by Anonymous Coward · 2012-11-08 04:00 · Score: 0
  
  all of this assuming carbon based life forms
9. Re:too heavy by mog007 · 2012-11-08 06:00 · Score: 1
  
  "Stellar" wind, would be the radiation emitted by any generic star.
  
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Habitable Planets might be rare by l810c · 2012-11-07 15:48 · Score: 5, Insightful

But what about moons?
We have found plenty of Jupiter size planets in the habitable zone.
Imagine a planet larger than Jupiter with 60 moons orbiting in the habitable zone. Many with liquid water.
I just marvel at the amount and diversity of moons in our own solar system. It seems like there would be far more moons in the habitable zone than planets universe wide.
Hopefully in the future we'll build some giant telescope and get a better answer.
1. Re:Habitable Planets might be rare by cameloid · 2012-11-07 16:01 · Score: 1, Offtopic
  
  Yeah, but one of those "moons" is probably going to be a Death Star. More than likely there to keep the local governors in line, or something...
  
  --
  -- Cisk for the Cisk God
2. Re:Habitable Planets might be rare by SlayerofGods · 2012-11-07 16:21 · Score: 1
  
  I have a gut felling that putting 60 earth sized objects in orbit around a Jupiter wouldn't work.
  Small planets don't fair that well... less you forget that our own moon is also in the 'habitable zone'
  
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3. Re:Habitable Planets might be rare by Anonymous Coward · 2012-11-07 16:41 · Score: 0
  
  I find no fault at all in your perspective, which has given me a new point of view. Thank you!
4. Re:Habitable Planets might be rare by Anonymous Coward · 2012-11-07 17:10 · Score: 0
  
  Atmosphere is what makes the difference.
5. Re:Habitable Planets might be rare by Anonymous Coward · 2012-11-07 17:53 · Score: 0
  
  And a magnetic field; both of which would be in short supply on any object small enough that you could place 60 of in orbit of a gas giant.
6. Re:Habitable Planets might be rare by wierd_w · 2012-11-07 18:11 · Score: 5, Insightful
  
  Just to play devil's advocate here.
  Let's assume that we have a neptune sized gas giant going through its daily grind around its parent star, and that it has a magnetosphere. (Only 1 in 50 red dwarf systems have a jupiter mass object in orbit, but 1 in 3 has a neptune mass object.)
  That close to its parent star, it would collect a tremendous amount of "cold" stellar plasma. (our little dirtball collects enough to create the van allen radiation belts. A neptune sized object would create a radiation torus MUCH larger.) This would inflate the magnetosphere to gargantuan proportions. This means that a great many of the proposed moons orbiting the gas giant would still retain thick atmospheres, unless other cosmic forces were actively at work to strip them. (like I think Enceladus's interaction with Saturn's magnetosphere...) Under such conditions, a rocky body like jupiter's moon Titan, which has a thick nitrogen and hydrocarbon atmosphere would be heated by both tidal heating, and be within the habitable zone. It would have an abundance of volcanic activity, and would get sufficient light that it could theoretically develop a biosphere.
  If you throw into the mix all the red dwarf stars in our local star cluster, and the shockingly large number of detected gas giant planets we have detected so far in "inner" solar system orbits, a solution to the problem of potentially habitable bodies in red dwarf systems becoming tide-locked is provided by moons orbiting habitable zone gas giants. Such systems would be well protected from meteor impacts, as the gas giant would sweep the vast majority of objects out of the orbital path of the pair. The gas giant would keep the rotation and orbital period of the moon on a nice even keel, and would provide a strong magnetosphere.
  If I were looking for a place to build a colony that could last a VERY VERY long time, I would look for goldilocks gas giants with habitable moons around red dwarf stars. The only niggly problem is the statistical scarcity of light elements like hydrogen in these systems. (M type stars are very rich in metals, but light on hydrogen and helium compared to more larger and more luminous stars. Any moons orbiting such gas giants are more likely to have an excessive amount of crustal oxygen than in other types of system, as metal oxide spectral lines are a mainstay feature of M type stars.) This might be resolvable if the system is "Absurdly old", as the high concentration of heavy elements would suggest a high level of radiological isotopes in the mineral composition of the planetary and satellite objects of such systems. This means that radiologically produced hydrogen from fission reactions over time could provide the missing hydrogen. M type star systems are quite capable of persisting to such advanced cosmic ages.
  I would be very interested in the prospect of habitable satellites of massive objects in red dwarf systems, and think that planets like ours get too much attention in the search for habitable bodies.
7. Re:Habitable Planets might be rare by Anonymous Coward · 2012-11-08 00:43 · Score: 1
  
  One small correction if I may: Titan is a moon of Saturn, not Jupiter.
8. Re:Habitable Planets might be rare by mcgrew · 2012-11-08 04:45 · Score: 2
  
  Small planets don't fair that well
  Well, sure they do. We have two state fairs in Illinois, plus a fair for every county. It's probably like that in most states, and probably every country has a few good fairs. So I'd say Earth fairs VERY well.
  As to the moon, there are no fairs on the moon but it fares pretty well where it's sitting.
  
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  Free Martian Whores!
9. Re:Habitable Planets might be rare by Tyndmyr · 2012-11-08 09:58 · Score: 1
  
  Nah, all of the Jovian moons have an induced magnetic field. No particular reason you couldn't have the same elsewhere.
  
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10. Re:Habitable Planets might be rare by Anonymous Coward · 2012-11-08 10:17 · Score: 0
  
  Give him a break, hes probably read AND seen 2001: A Space Odyssey, very confusing.
Wake me up when they find a second earth by Anonymous Coward · 2012-11-07 15:52 · Score: -1

I'm tired of hearing about newly discovered planets that are near or in the habitable zone but are blown out of proportion in ways that it would make civilizations unlikely to evolve. Sure, it's a possibility but I'm getting bored quickly until there's a second earth.
1. Re:Wake me up when they find a second earth by belthize · 2012-11-07 17:06 · Score: 4, Insightful
  
  I see no real point in waking you up, not like you're going to contribute anything when we do.
2. Re:Wake me up when they find a second earth by feedayeen · 2012-11-07 18:04 · Score: 4, Funny
  
  He's just waiting for us to find something 80% N2 and 20% O2 with 70% of it's surface covered in water before he unveils his warp teleporter.
3. Re:Wake me up when they find a second earth by coma_bug · 2012-11-07 23:02 · Score: 0
  
  Is this good enough?
Gravity by wisnoskij · 2012-11-07 15:59 · Score: 1, Interesting

I wonder if this will prevent walking animals.
I imagine a snake or a fish should not have nearly as much trouble as a dog or human.

--
Troll is not a replacement for I disagree.
1. Re:Gravity by Anonymous Coward · 2012-11-07 17:50 · Score: 0
  
  Many animals can carry twice their weight, from ants all the way up to humans.
Water by Anonymous Coward · 2012-11-07 16:12 · Score: 0

I think by now we all know water is important for life...can we stop pointing it out every time we talk about anything outside of earth?
1. Re:Water by MyLongNickName · 2012-11-07 16:21 · Score: 4, Interesting
  
  No, we can't. The reading population is not static and I don't see how including it hurts anyone.
  
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2. Re:Water by BeanThere · 2012-11-07 22:21 · Score: 4, Insightful
  
  The popular linguistic assumption/convention is that if water is not mentioned, it's probably absent.
  Let's rather stick to avoiding ambiguity. Otherwise you just know the first person who goes to a planet and finds no water, is going to sue, and lawyers have enough money.
3. Re:Water by Anonymous Coward · 2012-11-10 19:37 · Score: 0
  
  You want to send the population of Reading?
No problem by Sussurros · 2012-11-07 16:27 · Score: 2

Just hit the little button on the back of the Sontarans' helmets and they go down like a sack of potatoes.

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I said - don't look Ethel!..., but it was too late..., she'd already looked.
1. Re:No problem by Anonymous Coward · 2012-11-10 17:27 · Score: 0
  
  See now why didn't I think of that? Problem Solved.... NEXT!
We should probably hurry and try to get there by Anonymous Coward · 2012-11-07 17:45 · Score: 0

It might have oil.
1. Re:We should probably hurry and try to get there by symbolset · 2012-11-07 19:01 · Score: 2
  
  In our own solar system we have entire moons made entirely of hydrocarbons. No need to go to another star for that.
  
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2. Re:We should probably hurry and try to get there by jdray · 2012-11-08 07:57 · Score: 1
  
  Giving us the opportunity to ruin it shortly after we arrive.
  
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  Updated 6/28/2011
"So-called", it IS the Habitable Zone! by felixrising · 2012-11-07 17:47 · Score: 2

What's with the poor "Habitable Zone" being "So-Called"? That makes it sound like it's not the correct name for it, but being the correct scientific term, how can it be incorrect? Okay, maybe it's the "Circumstellar Habitable Zone", but come on!!! It IS the theoretically "habitable zone" of a parent star, you could call it the so-called "Goldilocks Zone", because the phase "Goldilocks Zone" is just colloquial. /me ends rant.
1. Re:"So-called", it IS the Habitable Zone! by Black+Parrot · 2012-11-07 18:01 · Score: 2
  
  What's with the poor "Habitable Zone" being "So-Called"? That makes it sound like it's not the correct name for it, but being the correct scientific term, how can it be incorrect? Okay, maybe it's the "Circumstellar Habitable Zone", but come on!!! It IS the theoretically "habitable zone" of a parent star, you could call it the so-called "Goldilocks Zone", because the phase "Goldilocks Zone" is just colloquial. /me ends rant.
  I think "Goldilocks zone" is actually better, because it's the zone that's "just right". "Habitable" isn't a boolean proposition everywhere.
  
  --
  Sheesh, evil *and* a jerk. -- Jade
2. Re:"So-called", it IS the Habitable Zone! by wonkey_monkey · 2012-11-07 20:12 · Score: 1
  
  What's with the poor "Habitable Zone" being "So-Called"? That makes it sound like it's not the correct name for it
  Actually it's a way of specifying that it is the correct and recognised name for it, rather than a phrase a journo has come up with for the purposes of this article. I agree that it can be read as being dismissive of the term, as well.
  
  --
  systemd is Roko's Basilisk.
3. Re:"So-called", it IS the Habitable Zone! by Anonymous Coward · 2012-11-07 23:26 · Score: 0
  
  What's with the poor "Habitable Zone" being "So-Called"?
  The "Habitable Zone" is basically just a region around a star in which we are most likely to find a planet with the right temperature ranges to support life... as we know it. It would be better to refer to it as more of a "sweet spot", calling it just the "habitable zone" implies that outside that zone is not habitable, which is most likely not the case.
Super-earth? by Black+Parrot · 2012-11-07 18:00 · Score: 1

Is this a dupe of yesterday's "we've now identified Krypton" story?

--
Sheesh, evil *and* a jerk. -- Jade
1. Re:Super-earth? by Anonymous Coward · 2012-11-07 20:16 · Score: 0
  
  This one is Kolob. We followed Mitt's trajectory as he left this planet for good. Good job America, you rejected the Messiah!
Direct imaging!? by Anonymous Coward · 2012-11-07 18:55 · Score: 0

The planet would be a prime target for space telescopes being designed that are sensitive enough to directly image relatively nearby Earth-sized worlds.
Haha. We can't even directly image all of the planets in our own solar system with space telescopes. How are we going to manage a relatively small planet in a solar system 42 light years away?
1. Re:Direct imaging!? by feedayeen · 2012-11-07 19:05 · Score: 4, Informative
  
  Taking pictures of bodies like Pluto isn't hard because it's far away from us, it's hard because it's far away from a light source and receives 1/2000th the illumination of the Earth, being small and far doesn't help, but that's not our big problem. Given that it's in the habitable zone, the amount of light should be comparable to that of the Earth, not something and given the expected surface area is nearly 4 times larger than that of the Earth's, it should be a quite bright pixel.
2. Re:Direct imaging!? by Anonymous Coward · 2012-11-07 19:19 · Score: 0
  
  Imaging and filtering techniques are always improving, but we're still some way from directly imaging a planet in another solar system _in the visible spectrum_. We can currently only do it for about a dozen exoplanets in the longer infrared and near-infrared wavelengths.
  This might change once the Gemini Planet Imager gets cranked up in 2013 at the Gemini South telescope on Cerro Pachon, Chile. Its Adaptive Optics imaging system will be about 10-100 times more sensitive than stuff used elsewhere.
3. Re:Direct imaging!? by Anonymous Coward · 2012-11-07 20:07 · Score: 1
  
  Or if we got a fucking move on and deployed a gravitational-lensing telescope to the outer solar system. But no, we "can't" afford to spend money on heavy interplanetary propulsion tech demonstrator missions, much less one with an actual science payload that could dwarf in significance all the data collected by all outer solar system programs so far.
4. Re:Direct imaging!? by Anonymous Coward · 2012-11-07 23:49 · Score: 0
  
  The planet would be a prime target for space telescopes being designed that are sensitive enough to directly image relatively nearby Earth-sized worlds.
  Haha. We can't even directly image all of the planets in our own solar system with space telescopes. How are we going to manage a relatively small planet in a solar system 42 light years away?
  Probably using these new space telescopes you mentioned.
5. Re:Direct imaging!? by dkf · 2012-11-08 01:59 · Score: 1
  
  But no, we "can't" afford to spend money on heavy interplanetary propulsion tech demonstrator missions, much less one with an actual science payload that could dwarf in significance all the data collected by all outer solar system programs so far.
  Of course not! It's far more important for society for that money to be spent on invading other countries and giving Bain Capital another tax cut...
  
  --
  "Little does he know, but there is no 'I' in 'Idiot'!"
6. Re:Direct imaging!? by Anonymous Coward · 2012-11-08 16:07 · Score: 0
  
  100 second exposures to compensate is not a problem at all....(human eye ~ 1/20 second).
Jinx? by roc97007 · 2012-11-07 19:04 · Score: 2

Just sayin'...

--
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Kobol? by wolverine1999 · 2012-11-07 21:09 · Score: 1

Wondering if this was Kobol'sstar?

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1. Re:Kobol? by tgd · 2012-11-08 00:59 · Score: 1
  
  Wondering if this was Kobol'sstar?
  No, Battlestar Galactica was a fictional story, not a documentary.
2. Re:Kobol? by rubycodez · 2012-11-08 03:42 · Score: 1
  
  it's historic fiction, has to be. I saw a number eight cylon starring in Hawaii Five-Oh.
3. Re:Kobol? by whitroth · 2012-11-08 06:21 · Score: 1
  
  No, it was Fortran
  mark
Obligatory Starship Troopers by Anonymous Coward · 2012-11-07 21:52 · Score: 0

Just hit the little button on the back of the Sontarans' helmets and they go down like a sack of potatoes.
"I don't get it, sir. I mean, what good is a knife in a nuke fight?"
"Your enemy cannot press a button, if you disable his hand!"
MEDIC!!
42 light years by TyFoN · 2012-11-08 00:03 · Score: 2

Maybe the answer is 42 :)
BUT.
42 light years at 10% of the speed of light (which is within the possibilities) and it would only take about 10 generations to reach this place.
It could actually be a place suitable for evacuation!
1. Re:42 light years by Anonymous Coward · 2012-11-08 01:29 · Score: 0
  
  Unless they are planning to evacuate coz of similar issues :)
2. Re:42 light years by Metabolife · 2012-11-08 02:02 · Score: 3, Funny
  
  Who would want to spend their entire life in a small room surrounded by their parents? Oh wait.. this is /.
3. Re:42 light years by CommieLib · 2012-11-08 03:14 · Score: 1
  
  Less if they're being chased by sexy robots.
  
  --
  If your bitterest enemies are people who hack the heads off civilians, then I would say you're doing something right.
4. Re:42 light years by rubycodez · 2012-11-08 03:44 · Score: 1
  
  less generations also, if they're *pursuing* sexy robots
5. Re:42 light years by Anonymous Coward · 2012-11-08 04:20 · Score: 1
  
  Unless they are planning to evacuate coz of similar issues :)
  Two colony ships pass in the interstellar darkness...
  Generations later, each arrives at its destination. One finds a world already stripped of its accessible resources, in the early stages of a runaway greenhouse; the other, a world rendered lifeless by a massive impact...
  Kind of "The Gift of the Magi" with a sci-fi twist.
6. Re:42 light years by EmagGeek · 2012-11-08 04:28 · Score: 1
  
  Don't forget that you would weigh almost twice as much when you got there...
Right, right... by jeffb+(2.718) · 2012-11-08 02:48 · Score: 1

..so maybe it's a mini-Mesklin?
Kimball Kinneson's buddy's homeworld by whitroth · 2012-11-08 06:20 · Score: 1

So, now we know where Valeria is.
mark
yet another interesting southern hemisphere star by 0111+1110 · 2012-11-08 10:33 · Score: 1

With a declination of -60 degrees this is yet another intriguing nearby star system that is best viewed/targeted from the southern hemisphere. The Alpha Centauri system is only about 1 degree further south. It really seems that the southern sky is way more interesting than the north. Of course the galactic center and the Wow signal location are also in the southern hemisphere. It's good that the SKA is being built there. It's too bad that China's giant Arecibo-killer dish is not.
This star would pass directly above your radio telescope (at your zenith) on Coronation Island in the Southern Ocean. Tierra del Fuego or at least southern Patagonia would be second best in terms of targeting and listening. I think it's about time we sent these guys a message. It's just too bad none of us currently reading this will be alive to hear any reply after more than 80 years of transit time. While we have our dish pointed that way we can also ping Alpha Centauri A and B. It's actually quite rude that we haven't already done so. The galactic community must regard us as antisocial, self-centered hermits.

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