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theCumCatcher t1_j2c36bd wrote

this is something i feel is missing from the explaination.

without our magnetic field, genetic life couldnt exist in the radiation produced by our star.... and even our atmosphere woule be eroded away by solar wind

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there is a HUGE difference between a 'dead' core and 'active' core world.

one has an atmosphere, magneticfield, and life.

the other, all things being equal, does not

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_AlreadyTaken_ t1_j2cdktk wrote

We wouldn't lose our atmosphere, Venus barely has a magnetic field and it has a very thick one. It helps us hold onto lighter elements. Water vapor could be photodissociated into oxygen and hydrogen and the hydrogen stripped away. We could also lose the ozone layer. There is even a weak spot in the magnetic field, the South Atlantic Anomaly.

You don't absolutely need it but it definitely helps.

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theCumCatcher t1_j2ew7u5 wrote

this is true. I worded my answer poorly.

the sun would irradiate anything alive on the surface while high energy particles whittled away at the ozone, making it worse.

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NOT TO MENTION, you are absolutely right with venus. it has gravty on its side, there

if we had a weaker pull, like mars, then in that case i think it would erode the atmosphere completely

I'll direct you to look at the MAVEN discoveries, to verify me there

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_AlreadyTaken_ t1_j2fmtd4 wrote

I'll toss out one more thing to think about. Life clearly evolved on earth before there was any ozone layer and ultraviolet light was bombarding the surface because it appeared before photosynthesis did so there was no free oxygen (or very very little) in the atmosphere to make ozone. So life can develop in spite of UV light, probably in water too deep for UV light to penetrate. Did photosynthesis evolve from mechanisms to protect against UV light in shallow water? Who knows...

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theCumCatcher t1_j2fnzk5 wrote

about the origin of photosynthesis.

I think there is something there.

if we look at the visible spectra of the sun,

https://www.sunlightinside.com/wp-content/uploads/2017/09/Sunlight_spectrum_Fiji_July.jpg

green and red are its largest components.

the protective pigments in leaves that reflect this red light (carotenoids) become visible when the chlorophil dies in the fall.

suspiciously, chlorophil reflects the remaining green part of the spectra almost perfectly

https://s3.amazonaws.com/microsite-cuny-prod/media/courseware/openstax/m66474/Figure_08_02_05abcd.jpg

it could be the chlorophylls evolved from one of these pigments.

thats really neat

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_AlreadyTaken_ t1_j2fp8nf wrote

I even read that purple bacteria appear to be older than chlorophyll photosynthesis. So either absorbing green, the peak of the solar spectrum is TOO much energy (heat can disable the enzymes) or that part of the spectrum was already filled by organisms so the green ones took what was left.

Chlorophyll is also composed of many subunits that likely have been added as enhancing features over time, like energy transmitting antennae structures that funnel the photon energy to the reaction center.

I used to date a woman who was researching the dna structure of photosynthetic bacteria. :D

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