7 ms·

Water Planets in the Habitable Zone

38 points by S4M 13y ago

claudius 13y ago
Now we just need FTL travel to get there.
- zokier 13y ago
  It's not that bad with non-FTL, about 10 years[1] on board with constant 1.5g acceleration (Kepler-62 is about 1200ly away). You wouldn't even need a real generation ship for that. Relativity would make it a long wait here on earth though. Of course even accomplishing that kind of acceleration would be a fairly major feat for humanity, but at least it wouldn't break any major laws of nature like FTL. [1] Calculated with this neat tool: http://mysite.verizon.net/res148h4j/javascript/script_starship.html http://mysite.verizon.net/res148h4j/javascript/script_starsh...
  - aardvark179 13y ago
    Have you tried applying the relativistic rocket equation to that little journey? A generation ship would be a considerably easier engineering problem than a rocket that can constantly accelerate at 1.5g for 10 years
    - zokier 13y ago
      The point I was trying to make was that while space is really really big place with vast distances, interesting destinations are still very much reachable with slower-than-light travel. Of course that doesn't make reaching those destinations easy, but it's still most likely significantly easier than FTL.
    - maaku 13y ago
      A generation ship is made pointless by technological advance. Why leave in a 1000yr generation ship now when it will only take 25 years to develop one which gets us there in half the time? And why then if another 25 years could cut that time in half again? For that matter, why not wait, say 150 years until a combination anti-matter / interstellar-hydrogen fueled engine that could accelerate at 1g for a decade? It'd be kinda silly to arrive 1000yr later only to find the system entirely colonized by people from the 'future'.
- spiritplumber 13y ago
  That's one possible solution to the Fermi paradox -- nobody's contacted us yet because they don't feel like trying to have a conversation with something that has the life span of a mayfly. http://www.terrybisson.com/page6/page6.html http://www.terrybisson.com/page6/page6.html
  - _of 13y ago
    I think the most likely explanation for the Fermi paradox is that civilizations destroy themselves before advancing to the stage where interstellar travel is possible. Look here at earth, all civilizations collapse sooner or later and this means that technology is forgotten or lost. Humans are too likely to engage in conflicts with each other before anything like interstellar travel will happen.
- icey 13y ago
  Something I've been thinking about a lot lately: if / when it becomes possible to "upload" our minds, wouldn't that be the ideal way to explore the universe? Space travel becomes much less daunting when you don't have to worry about an ordinary human lifespan, along with all the intricate & inefficient fueling and environmental needs a biological organism requires. I hope if there's ever an Kurzweilian singularity that the AIs come with a lust for discovering the universe and spread across it like dandelion seeds.
  - claudius 13y ago
    When. I am willing to bet that neither of us nor any of our grandchildren will be alive when it becomes possible to copy one’s personality onto a robot of sorts.
    - geuis 13y ago
      The future isn't something in the future anymore. We are living in the middle of it. I'm 33 and can easily see the effects of rapid technological change since the time I was a boy. Things are just getting faster. Betting against change has been a losing bet for decades, if not arguably centuries. As a practical example: solar power. It's been commercially a available for at least 30 years. It's often been derided and dismissed because even now, it's less than 1% of energy production in the US. 30 years of no significant traction, so an obvious loser right? Here's an Economist article from Dec. http://www.economist.com/blogs/graphicdetail/2012/12/daily-chart-19 http://www.economist.com/blogs/graphicdetail/2012/12/daily-c... The price per watt has been falling logarithmically. This corresponds to a rise in efficiency. If you look at the last 5 years or so, you can see that solar panels are starting to hit the up slope of a hockey stick. Within a very few number of years, be prepared to see an incredible impact on the energy industry. It's not going to make oil and gas obsolete, but we'll see cheap energy being used in lots and lots of places. My personal opinion, not really supported by hard data, is that we'll see an African renaissance in the next 10-20 years. Contrary to Western belief, Africa is not entirely desert and full of starving black kids who's parents are never around for some reason. It's also not entirely in some state of civil war. There's problems, but only in spots. What many African countries are doing is leap frogging into modern times. They are bypassing the massive infrastructures that Western nations have and using modern tech to fix their problems. With the spread of inexpensive solar power, you'll see the darkest night time parts of the continent lighting up.
motters 13y ago
In the search for exobiology one possible sign to look for within planetary spectra might be a predictable annual oscillation of carbon dioxide levels as occurs on Earth when plants photosynthesize more in the summer than the winter.
- sampo 13y ago
  When it's winter in the Northern Hemisphere, it's summer in the Southern Hemisphere, and vice versa. It's just the case with the Earth than most of the land masses are on the Northern Hemisphere, but would not necessarily be the case with another planet.
  - gus_massa 13y ago
    Yes, but it's even more complicated. According to Wikipedia (https://en.wikipedia.org/wiki/Oxigen#Photosynthesis_and_respiration https://en.wikipedia.org/wiki/Oxigen#Photosynthesis_and_resp... ), the green algae and cyanobacteria in the ocean produce between 70% and 45% of the free oxygen. (It's a lot of variation in the estimation.)
    - motters 13y ago
      True, but just measuring carbon dioxide for the whole planet does show a distinct seasonal variance and that's for the reasons previously stated - there's a lot of land mass in the northern hemisphere and terrestrial plant life has a significant effect. Possibly on exoplanets there might be similar asymmetries, or the asymmetry of an elliptical orbit. Seasonal variation in atmospheric gasses aren't necessarily a certain sign of life since there could be other non-biological causes, but they're a big clue.
  - maaku 13y ago
    Conflating two different effects. What you describe is due to the Earth's tilt. There's a smaller but globally significant effect due to moving closer/farther from the Sun in Earth's elliptical orbit.
- bane 13y ago
madaxe 13y ago
If I didn't know better, I'd say they're quietly and rightly cautiously hinting at the discovery of extrasolar photosynthesis. Their note about methane levels and the -f datum together draw an interesting picture.
- patdennis 13y ago
  You started your comment with "If I didn't know better". Do you know for a fact that they're not hinting at this? Or did I misread.
  - madaxe 13y ago
    Nah, I'm just a cynic at heart. I think they are hinting at it, but I'm probably wrong.
- n3rdy 13y ago
  If this is the case, dibs.
luke_s 13y ago
Disclaimer: I am not an exobiologist. Nor have I read more than the abstract and conclusion of the paper so far. However I do have an interest in exobiology and try to keep up with developments in the field. To summarize the paper: They have developed some new models that show it is theoretically possible that Kepler-62e and Kepler-62f could be warm water worlds. Their models also show that with the new generation of telescopes coming online, such as the James Web Space Telescope, it should be possible to determine if Kepler-62e and Kepler-62f are actually warm water worlds. If these two planets do turn out to be warm water worlds, it would be big news, as some of the elements for 'earth like' life would be present on two exoplanets – abundant liquid water. If I remember correctly, there is some other work being done (not related to this paper) on obtaining an atmospheric spectra of transiting exoplanets. This could tell us the chemical makeup of the planets atmospheres and we could possibly see various markers that would indicate life. All up, it looks to be pretty exciting, but we are going to need some bigger and better telescopes before we know more. Keep watching this space!

38 points by S4M 13y ago

claudius 13y ago

Now we just need FTL travel to get there.

zokier 13y ago
It's not that bad with non-FTL, about 10 years[1] on board with constant 1.5g acceleration (Kepler-62 is about 1200ly away). You wouldn't even need a real generation ship for that. Relativity would make it a long wait here on earth though. Of course even accomplishing that kind of acceleration would be a fairly major feat for humanity, but at least it wouldn't break any major laws of nature like FTL. [1] Calculated with this neat tool: http://mysite.verizon.net/res148h4j/javascript/script_starship.html http://mysite.verizon.net/res148h4j/javascript/script_starsh...
- aardvark179 13y ago
  Have you tried applying the relativistic rocket equation to that little journey? A generation ship would be a considerably easier engineering problem than a rocket that can constantly accelerate at 1.5g for 10 years
  - zokier 13y ago
    The point I was trying to make was that while space is really really big place with vast distances, interesting destinations are still very much reachable with slower-than-light travel. Of course that doesn't make reaching those destinations easy, but it's still most likely significantly easier than FTL.
  - maaku 13y ago
    A generation ship is made pointless by technological advance. Why leave in a 1000yr generation ship now when it will only take 25 years to develop one which gets us there in half the time? And why then if another 25 years could cut that time in half again? For that matter, why not wait, say 150 years until a combination anti-matter / interstellar-hydrogen fueled engine that could accelerate at 1g for a decade? It'd be kinda silly to arrive 1000yr later only to find the system entirely colonized by people from the 'future'.
spiritplumber 13y ago
That's one possible solution to the Fermi paradox -- nobody's contacted us yet because they don't feel like trying to have a conversation with something that has the life span of a mayfly. http://www.terrybisson.com/page6/page6.html http://www.terrybisson.com/page6/page6.html
- _of 13y ago
  I think the most likely explanation for the Fermi paradox is that civilizations destroy themselves before advancing to the stage where interstellar travel is possible. Look here at earth, all civilizations collapse sooner or later and this means that technology is forgotten or lost. Humans are too likely to engage in conflicts with each other before anything like interstellar travel will happen.
icey 13y ago
Something I've been thinking about a lot lately: if / when it becomes possible to "upload" our minds, wouldn't that be the ideal way to explore the universe? Space travel becomes much less daunting when you don't have to worry about an ordinary human lifespan, along with all the intricate & inefficient fueling and environmental needs a biological organism requires. I hope if there's ever an Kurzweilian singularity that the AIs come with a lust for discovering the universe and spread across it like dandelion seeds.
- claudius 13y ago
  When. I am willing to bet that neither of us nor any of our grandchildren will be alive when it becomes possible to copy one’s personality onto a robot of sorts.
  - geuis 13y ago
    The future isn't something in the future anymore. We are living in the middle of it. I'm 33 and can easily see the effects of rapid technological change since the time I was a boy. Things are just getting faster. Betting against change has been a losing bet for decades, if not arguably centuries. As a practical example: solar power. It's been commercially a available for at least 30 years. It's often been derided and dismissed because even now, it's less than 1% of energy production in the US. 30 years of no significant traction, so an obvious loser right? Here's an Economist article from Dec. http://www.economist.com/blogs/graphicdetail/2012/12/daily-chart-19 http://www.economist.com/blogs/graphicdetail/2012/12/daily-c... The price per watt has been falling logarithmically. This corresponds to a rise in efficiency. If you look at the last 5 years or so, you can see that solar panels are starting to hit the up slope of a hockey stick. Within a very few number of years, be prepared to see an incredible impact on the energy industry. It's not going to make oil and gas obsolete, but we'll see cheap energy being used in lots and lots of places. My personal opinion, not really supported by hard data, is that we'll see an African renaissance in the next 10-20 years. Contrary to Western belief, Africa is not entirely desert and full of starving black kids who's parents are never around for some reason. It's also not entirely in some state of civil war. There's problems, but only in spots. What many African countries are doing is leap frogging into modern times. They are bypassing the massive infrastructures that Western nations have and using modern tech to fix their problems. With the spread of inexpensive solar power, you'll see the darkest night time parts of the continent lighting up.

motters 13y ago

In the search for exobiology one possible sign to look for within planetary spectra might be a predictable annual oscillation of carbon dioxide levels as occurs on Earth when plants photosynthesize more in the summer than the winter.

sampo 13y ago
When it's winter in the Northern Hemisphere, it's summer in the Southern Hemisphere, and vice versa. It's just the case with the Earth than most of the land masses are on the Northern Hemisphere, but would not necessarily be the case with another planet.
- gus_massa 13y ago
  Yes, but it's even more complicated. According to Wikipedia (https://en.wikipedia.org/wiki/Oxigen#Photosynthesis_and_respiration https://en.wikipedia.org/wiki/Oxigen#Photosynthesis_and_resp... ), the green algae and cyanobacteria in the ocean produce between 70% and 45% of the free oxygen. (It's a lot of variation in the estimation.)
  - motters 13y ago
    True, but just measuring carbon dioxide for the whole planet does show a distinct seasonal variance and that's for the reasons previously stated - there's a lot of land mass in the northern hemisphere and terrestrial plant life has a significant effect. Possibly on exoplanets there might be similar asymmetries, or the asymmetry of an elliptical orbit. Seasonal variation in atmospheric gasses aren't necessarily a certain sign of life since there could be other non-biological causes, but they're a big clue.
- maaku 13y ago
  Conflating two different effects. What you describe is due to the Earth's tilt. There's a smaller but globally significant effect due to moving closer/farther from the Sun in Earth's elliptical orbit.
bane 13y ago

madaxe 13y ago

If I didn't know better, I'd say they're quietly and rightly cautiously hinting at the discovery of extrasolar photosynthesis. Their note about methane levels and the -f datum together draw an interesting picture.

patdennis 13y ago
You started your comment with "If I didn't know better". Do you know for a fact that they're not hinting at this? Or did I misread.
- madaxe 13y ago
  Nah, I'm just a cynic at heart. I think they are hinting at it, but I'm probably wrong.
n3rdy 13y ago
If this is the case, dibs.

luke_s 13y ago

Disclaimer: I am not an exobiologist. Nor have I read more than the abstract and conclusion of the paper so far. However I do have an interest in exobiology and try to keep up with developments in the field. To summarize the paper: They have developed some new models that show it is theoretically possible that Kepler-62e and Kepler-62f could be warm water worlds. Their models also show that with the new generation of telescopes coming online, such as the James Web Space Telescope, it should be possible to determine if Kepler-62e and Kepler-62f are actually warm water worlds. If these two planets do turn out to be warm water worlds, it would be big news, as some of the elements for 'earth like' life would be present on two exoplanets – abundant liquid water. If I remember correctly, there is some other work being done (not related to this paper) on obtaining an atmospheric spectra of transiting exoplanets. This could tell us the chemical makeup of the planets atmospheres and we could possibly see various markers that would indicate life. All up, it looks to be pretty exciting, but we are going to need some bigger and better telescopes before we know more. Keep watching this space!