Number of Habitable Exoplanets Found by NASA's Kepler May Not Be So High After All
The tally of potentially habitable alien planets may have to be revised downward a bit. To date, NASA's prolific Kepler space telescope has discovered about 30 roughly Earth-size exoplanets in their host stars' "habitable zone" — the range of orbital distances at which liquid water can likely exist on a world's surface.
Or so researchers had thought. New observations by the European Space Agency's (ESA) Gaia spacecraft suggest that the actual number is probably significantly smaller — perhaps between two and 12, NASA officials said today (Oct. 26)
[...] Gaia's observations suggest that some of the Kepler host stars are brighter and bigger than previously believed, the officials added. Planets orbiting such stars are therefore likely larger and hotter than previously thought.
Also at NASA.
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NASA Retires Kepler Space Telescope
After nine years in deep space collecting data that indicate our sky to be filled with billions of hidden planets - more planets even than stars - NASA's Kepler space telescope has run out of fuel needed for further science operations. NASA has decided to retire the spacecraft within its current, safe orbit, away from Earth. Kepler leaves a legacy of more than 2,600 planet discoveries from outside our solar system, many of which could be promising places for life.
"As NASA's first planet-hunting mission, Kepler has wildly exceeded all our expectations and paved the way for our exploration and search for life in the solar system and beyond," said Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate in Washington. "Not only did it show us how many planets could be out there, it sparked an entirely new and robust field of research that has taken the science community by storm. Its discoveries have shed a new light on our place in the universe, and illuminated the tantalizing mysteries and possibilities among the stars."
(Score: 2) by ikanreed on Tuesday October 30 2018, @03:56PM (14 children)
At this point, I thought the big question was "potentially life bearing" as a big open-question research thing.
If we had the resources and technology needed to get our gooey flesh-bag selves to these planets for colonizing, we'd have the resources and technology to rearrange our own solar system to increase the amount of Goldilocks planets massively. Steal all of jupiter's moons and place them in between earth and mars' orbit.
(Score: 4, Informative) by Runaway1956 on Tuesday October 30 2018, @04:02PM (12 children)
We can't even engineer a parasol to shield the earth from part of the sun's emissions. I don't mean to put the earth in darkness - just a parasol or mirror to deflect a small percentage of the energy we absorb. The greenhouse won't heat up, if the excess energy is deflected away, can it? What would it take - a 3% reduction in sunlight? 6%? Just put a mirror up there, and move it closer to the sun to block out more of the sun. Something the size of Delaware, for starters? Or, the size of Texas?
Seriously, if we can't invent and operate a simple window shade, we'll never move moons around.
(Score: 2) by ikanreed on Tuesday October 30 2018, @04:58PM (6 children)
The problem with this strategy, is while it's sufficient to mitigate climate change up to around 350 ppm(given the numbers you provide and some napkin math), it also diminishes, you know, plant and algae growth. Which are big ol carbon sinks. And sources of food. 3-6% less food might be semi-sustainable, but it's a biiiiiiiiiig cost. I'm sure you can further spitball megaengineering solutions to these problems, but I just want to say it's not as easy as just flying into space with a couple million tons of light-weight titanium alloys, and calling it done.
Also, if anything, I have to imagine a sustainable future brings in higher insolation to increase the sustainable energy base.
(Score: 3, Informative) by takyon on Tuesday October 30 2018, @05:03PM (5 children)
https://www.technologyreview.com/s/511016/a-cheap-and-easy-plan-to-stop-global-warming/ [technologyreview.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by ikanreed on Tuesday October 30 2018, @05:12PM (1 child)
Consider me fully informed on the aerosol proposals. "what if we brought back acid rain?" is sure a take on climate change, though.
(Score: 3, Interesting) by takyon on Tuesday October 30 2018, @05:30PM
We currently emit the stuff near the ground. Switch to electric cars, solar, fusion, etc. and inject it into the stratosphere instead. FTA you were fully informed about:
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Tuesday October 30 2018, @05:16PM (2 children)
Ah, I always wondered what the humans in the Matrix world did to "scorch the sky."
(Score: 2) by takyon on Tuesday October 30 2018, @05:34PM (1 child)
Ah, yes. The movie that justified using humans as "batteries" by throwing in "a form of fusion". That even more vague throwaway line should definitely inform our geoengineering efforts.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Tuesday October 30 2018, @10:44PM
I think it was all explained in the animatrix.
(Score: 2) by takyon on Tuesday October 30 2018, @05:04PM (2 children)
https://www.technologyreview.com/s/511016/a-cheap-and-easy-plan-to-stop-global-warming/ [technologyreview.com]
https://www.technologyreview.com/s/603974/harvard-scientists-moving-ahead-on-plans-for-atmospheric-geoengineering-experiments/ [technologyreview.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 1) by Sulla on Tuesday October 30 2018, @08:44PM (1 child)
So those articles are from 2013 and 2016, has there been any update on the real world test of this using a balloon? I was going to go down the rabbithole of reading the documentation on the Keith Group website but if you already have it would save me some time.
Ceterum censeo Sinae esse delendam
(Score: 2) by takyon on Tuesday October 30 2018, @09:02PM
Planned for Spring to Fall 2019:
https://projects.iq.harvard.edu/keutschgroup/scopex [harvard.edu]
https://www.technologyreview.com/s/611682/how-one-climate-scientist-combats-threats-and-misinformation-from-chemtrail-conspiracists/ [technologyreview.com]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Tuesday October 30 2018, @08:51PM (1 child)
Or instead of cluttering up outer space even more, make vast tracts of those films that radiate in the "window" of infrared wavelengths that go readily through the atmosphere.
e.g. https://soylentnews.org/article.pl?sid=18/10/28/008223 [soylentnews.org]
e.g. https://soylentnews.org/article.pl?sid=17/09/05/0250247 [soylentnews.org]
(Score: 0) by Anonymous Coward on Tuesday October 30 2018, @08:54PM
...and pave the Earth [archive.org] with the stuff.
(Score: 3, Interesting) by Thexalon on Tuesday October 30 2018, @06:19PM
That's what the "habitable zone" thing is supposed to be about: narrowing down where we should be looking for ETs. Since the one planet we know about that has life on it has lots of liquid water and that liquid water is essential to all life on that planet, exobiologists figured odds were better for life on planets where there could be liquid water. That means not too far away from the star (which leads to ice like Mars has), and not too close (which leads to no water like Mercury). It's of course not guarantee: Venus is also in the habitable zone, but any ETs there fried thanks to unchecked global warming.
This isn't the same thing as figuring out where we're going to colonize. Heck, we haven't even gotten people any further than our own largest moon, and even then we didn't stick around for long.
The only thing that stops a bad guy with a compiler is a good guy with a compiler.
(Score: 0) by Anonymous Coward on Tuesday October 30 2018, @09:11PM (2 children)
The calculation ignores the heat capacity and rotation rate of the planet. Just compare to the LRO diviner data on moon temperatures. The average tempetature is like 100K less than what they "predict" for a planet without an atmosphere in Earth's orbit (255 K).
https://www.sciencedirect.com/science/article/pii/S0019103516304869 [sciencedirect.com]
(Score: 2) by takyon on Tuesday October 30 2018, @09:33PM (1 child)
There is no single agreed-upon calculation for the habitable zone.
The potential habitability applies to planets in the zone that are at least Earth-like (rocky and similar in size). A Neptune-sized planet in the zone won't matter, unless it has a large satellite. A Pluto or Moon-sized planet probably won't matter.
Studies have taken into account rotation rate, and have considered the possibility of a narrow habitable band where the light and dark sides of a tidally locked planet meet.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 0) by Anonymous Coward on Tuesday October 30 2018, @09:57PM
The calculation doesnt even work for the case of the earth.