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  1. #161
    Tekki's Bitch
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    These bein the planets that were talked about today.


    How true is this? Can I get a Sath feedback?
    I thought scientists agreed M-Class stars can't support life (as we know it). They emit almost no UV radiation (which plants need for photosynthesis), and they're luminosity is so low that in order to stay warm enough to have liquid water, a planet has to orbit so close that the star's gravity stops it from spinning and it becomes tidally locked (like the Moon is tidally locked to the Earth) leaving one side in perpetual daylight and the other in perpetual darkness.

    Also, it doesn't help that younger red dwarfs are prone to extremely violent solar flares that make the biggest flares we've seen with our own sun seem babby tier by comparison.

    If you want truly Earthlike worlds, your best bet is to look around K stars, or G type stars like our sun, and perhaps occasionally around F stars.

  2. #162
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    The scientists said those planets are tidally locked and since it's a very small dim star the close distance will keep the planets warm enough however, the close proximity puts it in danger of solar flares which could strip the atmosphere.

  3. #163
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    They are going too fast, we're just gonna fly off into space. Jeez.

  4. #164
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    e looks closest to the earth. Count me in for 6 day years instead of weeks.

    But jesus those are close as fuck to their sun. Even if its a cool dwarf dude.

  5. #165
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    I have a fairly serious medical question to ask, if I dont ask it, please ban me.

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    Quote Originally Posted by TummieGaruda View Post
    The scientists said those planets are tidally locked and since it's a very small dim star the close distance will keep the planets warm enough however, the close proximity puts it in danger of solar flares which could strip the atmosphere.
    This answers TPG's questions. They are most definitely tidally locked and as I've tried to explain many times today, there's an innumerable amount of factors to consider that we dont have the ability to measure wrt exoplanets that are more than just "how big is it, how far is it from the host star" before we should even start having a discussion about anything other than pure planetary system dynamics.

  6. #166
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    I have a fairly serious medical question to ask, if I dont ask it, please ban me.

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    I couldn't remember exactly why I was getting so hung up on "earth-like" and "habitable zone" having any real meaning for life or habitability
    but it has been bothering me because I knew that while it is important to investigate these targets, those qualities alone don't actually mean fuck all.

    This got me searching my email because I remember getting an internal release pre-print last year about the weather on ProxCen B, an earth-like planet in the habitable zone only 4Ly away, literally our closest extra solar planet and it happens to be E-L and in H zone.

    Paper has since been published so here is the link https://arxiv.org/pdf/1609.09076.pdf

    Highlights a lot of factors that even I hadn't really thought about in terms of exoplanet viability from an astrobiology standpoint. From the abstract of the paper...

    "the planet is subject to stellar wind pressures
    of more than 2000 times those experienced by Earth from the solar wind. During an
    orbit, Proxima b is also subject to pressure changes of 1 to 3 orders of magnitude on
    timescales of a day. Its magnetopause standoff distance consequently undergoes sudden
    and periodic changes by a factor of 2 to 5. Proxima b will traverse the interplanetary
    current sheet twice each orbit, and likely crosses into regions of subsonic wind quite
    frequently. These effects should be taken into account in any physically realistic
    assessment or prediction of its atmospheric reservoir, characteristics and loss."

    Anyway, the new exoplanets are still interesting but it is good to remember that space is complicated, and trying to reduce viability down to just a few sweeping generalizations is bad.

  7. #167
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    Quote Originally Posted by SathFenrir View Post
    I couldn't remember exactly why I was getting so hung up on "earth-like" and "habitable zone" having any real meaning for life or habitability
    but it has been bothering me because I knew that while it is important to investigate these targets, those qualities alone don't actually mean fuck all.

    This got me searching my email because I remember getting an internal release pre-print last year about the weather on ProxCen B, an earth-like planet in the habitable zone only 4Ly away, literally our closest extra solar planet and it happens to be E-L and in H zone.

    Paper has since been published so here is the link https://arxiv.org/pdf/1609.09076.pdf

    Highlights a lot of factors that even I hadn't really thought about in terms of exoplanet viability from an astrobiology standpoint. From the abstract of the paper...

    "the planet is subject to stellar wind pressures
    of more than 2000 times those experienced by Earth from the solar wind. During an
    orbit, Proxima b is also subject to pressure changes of 1 to 3 orders of magnitude on
    timescales of a day. Its magnetopause standoff distance consequently undergoes sudden
    and periodic changes by a factor of 2 to 5. Proxima b will traverse the interplanetary
    current sheet twice each orbit, and likely crosses into regions of subsonic wind quite
    frequently. These effects should be taken into account in any physically realistic
    assessment or prediction of its atmospheric reservoir, characteristics and loss."

    Anyway, the new exoplanets are still interesting but it is good to remember that space is complicated, and trying to reduce viability down to just a few sweeping generalizations is bad.
    Plus they are moving way too fast. We'd fly right off.

  8. #168
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    Quote Originally Posted by Zetanio View Post
    Plus they are moving way too fast. We'd fly right off.
    U r 2 speedy 4 me

  9. #169
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    dat wat i sed to nasa but dey dun lissn

  10. #170
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    Nasa uploaded a video of what the entirety of Earth's Moon looks like last July and are just sharing it now.


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