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Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

arxiv.org

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Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#41

Post by loxias »

adastra22 wrote: post #35
loxias wrote: post #30

Earlier quoted context omitted.

Over the course of the past 2 decades we've gone from "perhaps some day we'll find extra solar planets" to "most if not all stars have planets". JWST's already found water. At this point it's no longer a matter of if but when extrasolar life will be confirmed, and with which instrument. Might be JWST, might be WFIRST, might be HabEx.

By the standards of astrobiology, none of those instruments are capable of detecting life. But they might detect telltale signatures of biosphere in extrasolar atmospheres, which will trigger decades of debate as to whether there is life.

I am not a biologist. I could be entirely wrong in which case please educate me. :)

My understanding was that life would be "detected" by finding chemical signatures in the atmosphere which could not exist at a "steady state" without biological creatures there doing things. Is this what you mean by telltale signatures?

(A++ username)

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#42

Post by rendall »

moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

You're saying that all Earth-sized planets without moons are tidally locked?

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#43

Post by mach1ne »

loxias wrote: post #25
ttul wrote: post #3

A little farther out than Wolf 359, where of course humanity will one day battle the Borg.

We were all thinking it. I am NOT looking forward to the Bell Riots next year. Being as I lived in SF in the late aughts, me and other friends would joke about the Bell Riots. Then 2016 happened, then 2020 happened, and all of a sudden it's not a very funny joke. :(

Don't worry, it will cause the public opinion to finally turn against the Sanctuary Districts.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#44

Post by adastra22 »

loxias wrote: post #41
adastra22 wrote: post #35

Earlier quoted context omitted.

By the standards of astrobiology, none of those instruments are capable of detecting life. But they might detect telltale signatures of biosphere in extrasolar atmospheres, which will trigger decades of debate as to whether there is life.

I am not a biologist. I could be entirely wrong in which case please educate me. :) My understanding was that life would be "detected" by finding chemical signatures in the atmosphere which could not exist at a "steady state" without biological creatures there doing things. Is this what you mean by telltale signatures? (A++ username)

Yes, astrobiologists distinguish between direct detection of life and biosignatures. The latter are things for which we don’t have non-biological explanations at this time, but which we don’t consider adequate evidence by themselves for life.

FWIW we’ve already detected bio signatures for life in the atmosphere of Mars (seasonal methane emissions). And maybe Venus, though that is less clear.

(Thanks!)

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#45

Post by nakedrobot2 »

moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

If they're one in a billion, there are still billions of them.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#46

Post by govg »

skykooler wrote: post #29
HyperSane wrote: post #21

Earlier quoted context omitted.

The Solar Gravitational Lens is very neat but with current propulsion technology it would take a very long time to get the satellites into position. https://www.youtube.com/watch?v=NQFqDKRAROI&t=411s

Then we'd better start as early as possible.

There's a funny paradox-like situation that arises in space flight where because of the distances involved/ time taken, it might be better to wait some time for a faster method of flight to develop. Of course, it is up for debate whether there are many more ways of propulsion that are yet to be invented.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#47

Post by danw1979 »

nakedrobot2 wrote: post #45
moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

If they're one in a billion, there are still billions of them.

… but so far apart we’ll likely never meet or even hear from them ?

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#48

Post by danw1979 »

BeefWellington wrote: post #32
djmips wrote: post #19

Earlier quoted context omitted.

Why not Wolf 1069B? Kepler-452b has 2X Earth gravity.

Kepler-452b has 2X Earth gravity. Eternal leg day. But seriously, these are all too far away for us to reach in any of our lifetimes, barring some insane discovery that breaks all the rules as we know them.

Fusion propulsion, clever shielding and general relativity gets you anywhere in the galaxy in your lifetime, or so I thought …

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#49

Post by bagels »

moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

Mars and Venus are not tidally locked.

Earth, Jupiter and Ganymede have magnetic fields, and Mars used to.

Do we know that these exosolar planets don't have moons, don't have magnetic fields, and are tidally locked?

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#50

Post by moloch-hai »

rendall wrote: post #42
moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

You're saying that all Earth-sized planets without moons are tidally locked?

All such planets orbiting so close to their star are certainly tidally locked.

Even Venus is almost tidally locked, tens of millions of miles away from the sun. All moons in our solar system are locked. It is the norm.

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