Slashdot Mirror
Earthlike Planet Orbiting Nearby Star
The Bad Astronomer writes "Astronomers in Europe have announced the discovery of a planet with only 5 times the Earth's mass, orbiting a red dwarf star 20 light years away. It orbits the star so closely that it only takes 13 days to go around... but the star is so cool that the temperature of the planet is between 0 and 40 Celsius. At this temperature there could be liquid water. Models indicate the planet is either rocky like the Earth or covered in an ocean. While it's not known if there actually is liquid water on the planet, this is a really big discovery, and indicates that we are getting ever closer to finding another Earth orbiting an alien star."
So, the temperature range indicates that it can probably be made hospitable for humans. Sure, we might have to bring a lot of our own oxygen and water to start with, but otherwise, we just need a colony ship. And, of course, the gravity is pretty strong (2.25 Gs) so we will have trouble with that. And, it being so close to the star, there might be a big radiation problem, forcing humans to go underground. But that wouldn't be too bad, because it would make gravity a bit less of a problem.
What I think is the coolest thing is that this is the smallest extrasolar planet found so far. We are getting close to being able to detect earth-sized planets. Once we do, I think the number of potentially colonizable planets will go up quite a bit.
We are currently developing technologies which allow a maximum speed of 0.6 X the speed of light.
if you create a probe with an ion drive and send it off in the next 10 years we could be looking at surveys of the planet in question by 2070.
VLC FOR MAC IS DYING! IF YOU DEVELOP, PLEASE SAVE IT!!
I am not religious, I am an Atheist. I have no "God" to look forward to meeting (I don't believe anyone else does either but anyway). My biggest hope is that before I die we will have proof of alien life, hopefully a spaceship will land in Times Square so there will be know question about it. This is a very exciting time, every time Scientists make a new discovery like this I feel that much closer to my dream.
If you could reason with religious people, there would be no religious people
It is good to see everyone has a positive attitude for space exploration. I must assume that, in your opinion, there is no good reason to go to Mars or the Moon?
Also remember that were you got the information on gravitational pull and the atmosphere for this planet is speculative at best.
1) 2.25 times that of our own gravitational pull would not be ideal for us to live but, it doesn't mean nothing could live there. I pull 2.25g's with my car on a dry skid pad, I have not died yet.
2) Really?
3) Yes the planet is closer to its sun that ours, but if this planet is like ours, the atmosphere filters out most of the radiation. The star closest to them does not spit out the magnitude of radiation that ours does due to its size.
4) If there is atmosphere like ours with water in it, it will hold some of the heat as it passes out of its suns rays and therefore should be just as turbulent.
Also some things to think about:
Even if the planet is 2 times as big as our planet, it could be spinning faster than ours. This would help off set the gravitational pull on our bodies at the surface.
No one is saying this is a planet to colonize, but with some of our technology and determination, it could be a waypoint in the stars for us to refuel and grab water before we continue our adventures further into space.
Just my two cents,
-X
The first thing that popped into my mind when I read the description, for some reason, was the world of Charn from the Chronicles of Narnia, with this huge, dim red sun in the sky.
I haven't run any mathematical models, but given that there's a Neptune-mass (15 Earth mass) planet orbiting inside this planet's orbit (5.4 day orbit vs 13 day orbit), I'd guess that that's enough of a disruption to at least prevent a 1:1 tidal lock. There may be some kind of lock at another resonance (eg Mercury's 2:3 lock) but that would allow for rotation relative to the star and thus more-even heating.
2.25 gees is uncomfortable but tolerable (carry someone your own weight piggyback and you're almost there), and largely irrelevant to any water-dwelling critters.
However, the larger problem -- that I didn't see any of the articles explicitly raise -- it that there's likely a Venus-like greenhouse with the temperature much hotter than the 0-40C based on the equilibrium temperature of a rocky body at that distance from the primary. We can hope not, but we'd need a reason why not.
Based on our system, anything Venus-size or larger has a thick atmosphere, except Earth, and Earth is an anomaly because it got whacked by something massive (Mars mass) late in its formation, blowing most of the volatiles -- and the material that makes up the Moon -- off the planet altogether. (However, such late-stage super-impacts may be not all that unusual; it could explain some other oddities of our system, such as Uranus's tilt.)
-- Alastair
Mars? Sure. Moon? Sure. I can do things there. But 2.25 G's?? Ok, it's not immediately lethal, but it is rather limiting. The only way one could reasonably move around there is as in your car - belted into a seat in some kind of vehicle. I wouldn't dare walk around, for a simple fall could kill.
Two words: inertial dampers.
l
Two other words: Relativity, and Acceleration.
I've read[1] that if we accelerate consistently at 1G we'll reach 0.77 C in 1 year. However, as we continue to accelerate closer to C, we get more and more relativistic and things get screwy... screwy to the point that I'll estimate it would take about 6 years (that's 6 rocket years, not earth observer years) to get there, with 1G accel and 1G deccel. So, human travel would be extremely feasible.
While a probe could accelerate much harder, I figure it would still take 50 years or so to get results from a probe to confirm it's worth sending people.
1. http://www2.corepower.com:8080/~relfaq/rocket.htm
Forget thrust, drag, lift and weight. Airplanes fly because of money.
We are currently developing technologies which allow a maximum speed of 0.6 X the speed of light.
if you create a probe with an ion drive and send it off in the next 10 years we could be looking at surveys of the planet in question by 2070.
Again, correct me if I'm wrong but according to http://nmp.nasa.gov/ds1/tech/ionpropfaq.html, ion drives only deliver 10x the efficiency of chemical rockets. So to reach 0.6c, wouldn't an ion drive require more propellant than exists in the universe?
We don't have a people shortage, or even a crazy people shortage. Skip the probe and send volunteers. Promise enough funds to support their families for life and you will get cheap volunteers from third world nations that are throwing babies into rivers due to overpopulation. You can't lose.
Actually, since you can only asymptotically approach the speed of light, it's meaningless to draw any inferences about what happens when you reach it based solely on Special Relativity. Also, note that Beta, your fraction of the speed of light, equals 1, and so most of the transformations for Special Relativity that depend on Gamma are being divided by zero, indicating that the law breaks down completely at the speed of light.
The Calculus result after you take the limit is physically meaningless, in my opinion. It only tells you what's happening as you get close to the speed of light, not when you hit the speed of light.
If you didn't understand what I just said, pick up a decent Modern Physics textbook and study the relations. Then argue away.
SRSLY.
The star is only about 47%-56% enriched as our Sun in elements heavier than hydrogen, so it stands to reason that any planets that formed around the star are similarly deficient in heavy elements/metals. See the following web page about the star, but keep in mind it has not been updated with this latest planetary information:
http://www.solstation.com/stars/gl581.htm>4) If there is atmosphere like ours with water in it, it will hold some of the heat as it passes out of its suns rays and therefore should be just as turbulent.
A planet orbiting this close will likely be in tidal lock with one side always facing the star. This would have unplesant effects on any atmosphere.
What about people that gain weight going from ~ 120lbs to say, 260. As its done over time, the body adapts and they are still able to walk around and live normally (although it does have adverse health effects) I think it is possible for people to adapt, but it will not be comfortable, especially for the first generation, and they will probably live a lot shorter. If this doesn't work however, It may however be possible to genetically engineer humans to live on high-G environments, increasing muscle mass, and bone density and thickness, as well as cardiovascular improvements.
I am aware of one experiment of putting someone in a high-G centerfuge and subjecting him to 1.5G's. The experiment was terminated early, due to the participant having a mild heart attack. Keep in mind, the participant wasn't given time to acclimate to the new environment gradually, and the experiment was short in duration, lasting only about a week, as it was designed more towards seeing if a high-G environment could help astronauts overcome loss of muscle mass and bone decalcification faster than normal after returning to earth, rather than colonization of a high-G environment.
All misspellings and grammatical errors in the above post are intentional and part of my artistic expression.
I wanted to mod you up but couldn't resist asking a question.
What about space dust? INAA (I'm not an astro-physicist)but I don't think that the main problem is a lack of speed. Eventually we will work out how to go faster and faster. For me the problem is those little bits of rock and grit in the way. Even at 0.75C travelling in the not-quite empty vastness of space would be like standing in front of a machine gun going full-on.
Travelling forward in time at a rate of 1 second per second.
With 5x the mass of the Earth, the atmosphere would be something more akin to Venus than something more like the Earth or Mars. Still, this is something that would be interesting to try and speculate about in terms of a fictional story about going to this planet.
Unless this planet also had a collision with a similarly sized planetoid (such as is speculated with the Earth and the current favored theory of the creation of the Moon) that would have stripped much of the original atmosphere away, I don't see how this planet could have a lower pressure atmosphere than found on the Earth and likely would be much higher.
What would be interesting would be to find out what the density of this planet could be. A highly dense object (aka this huge mass and nearly the same size of the Earth) would have a huge surface gravity, but if this planet were mainly made up of water or other lighter compounds, it would be a "waterworld" that would be several times the size of the earth in terms of area and may even have Earth-like gravity on the surface.
Regardless, nearly any possible model you could come up with here would have sufficient atmosphere to allow water in a liquid state at these temperatures. The only exception would be if the atmosphere was so dense like Venus that run-away greenhouse gasses would make the surface temperatures far too hot. Venus doesn't get that much more additional sunlight (measured in watts/cm^3) than the Earth, but it is much hotter than even the surface of Mercury.
I admit not having had the time to scan through all the comments on this article- but it raises an interesting point in my mind, relating to another recently-discussed discovery, that being of the fellow that found "kryptonite" in a Serbian mine... if we have found kryptonite on Earth now, and it would appear (from the gravity/mass/star-type data) we have now found "Krypton" the planet... should we begin to search the midwestern US for a "really strong kid" ??
Rule of Acquisition #19: Satisfaction is Not guaranteed.
If humanity is able to stabilize its population, then the Earth should not 'fill up'. In many places, birthrates are falling. Europe, Japan, South Korea, and (maybe) the U.S. and China have birthrates less than the replacement rate (~2.1 children per woman). One of the suggested explanations for this is the spread of women's rights in these countries. To combat overpopulation, the developed countries should offer incentives for reducing birthrates, such as offering billions of dollars in financial aid for every percentage decline in the growth rate of a third world country. The chief cause of environmental destruction is population growth, so if we can stabilize (or even reduce) the world population and switch to cleaner energy sources, a lot of our environmental worries should be solved. However, if the world population is reduced, one of the prime impetuses for outerspace colonization will be lost.
---- "XML is like violence. If it doesn't fix the problem, you aren't using enough."