Alternate planets, suns, stars, and solar systems thread page 3 alternate history discussion gas and water mix

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Mars is in a closer orbit coupled with a full-sized moon and a diminutive asteroid as well as the positive effects of an active magnetic core have made incredible changes to Mars. No longer a dying world the red planet is still red, but green and blue also invade the surface. With a gravity about half that of Earth’s, and a atmosphere roughly comparable to our own Mars is a lush planet with large Iron-rich deserts, and the solar system‘s largest active super volcano.

Scientists believe that the ring system of Venus was formed after two Moon-sized object collided hundreds of millions of years ago. The asteroid debree couldn’t reform into a moon, and instead became trapped in a circularized orbit around the planet Venus. Venus is the only Terrestrial planet in our solar system to have developed rings like the outer gas giants, and even though the rings have consolidated their orbit at an equatorial 125 km circular orbit they are visible from almost everywhere on the surface of the planet.

Venus itself has a uninhabitable moon, approximately the same size as our own Moon. This moon has over the eons stabilized the rotation of Venus, and allowed an 28 hour "day." Venus is a wet jungle world, drier then Earth but wetter then Mars or Vega. Scientists have calculated that 65% of Venus is covered by water, and that ninety-three percent of the water on Venus is salt water. Air pressure and Gravity are both approximately 85% that of "normal sea-level" conditions on Earth.

Vega is the Mars analogue planet, dead or dying – just on the border of the inner habitable zone, and close enough to the asteroid belt to guarantee the capture of a number of asteroids from the main belt Vega is about as inhospitable as they come. Vega has no active core, and it has a surface water percentage of 15% liquid water on its surface which is quickly evaporating along with the decaying atmosphere.

Wolf-Rayet blue giants produce large amounts of Fluorine. Here is a system which began as a W-F blue supergiant (something like the Pistol Star) and a small Type A white star (about the size of Sirius). The supergiant lasted less than a million years before exploding spectacularly as a supernova. This explosion bathed the companion star and its coalescing planets in the stellar material of the W-F, along with its peculiar Fluorine content. A a result, all of the planets in the system contain a great deal of it.

Shamash, within the liquid range of Hydrogen Fluoride, contains great yellow seas of the stuff, teeming with HF life, whose cells are surrounded by membranes of CF chains, and whose biological processes are carried out by exotic organo-fluorine compounds. Hurricanes lash the coasts, rivers of HF flow down from craggy highlands.

Marduk is a gas giant about the mass of Neptune, stained bright yellow by Fluorine in its clouds. It is orbited by several moons, one of which, Amathaunta, contains a subsurface sea of HF heated by tidal forces. Life is driven by great convection currents caused by the sinking of solid HF on the surface (bordering the liquid HF and the vacuum of space), its melting in the warmer depths, and subsequent rising to be frozen on the surface again. A soup of HF, HCl, HBr, and halides of various other nonmetallic elements drives a complex and rich biosphere.

Mars is in a closer orbit coupled with a full-sized moon and a diminutive asteroid as well as the positive effects of an active magnetic core have made incredible changes to Mars. No longer a dying world the red planet is still red, but green and blue also invade the surface. With a gravity about half that of Earth’s, and a atmosphere roughly comparable to our own Mars is a lush planet with large Iron-rich deserts, and the solar system’s largest active super volcano.

Scientists believe that the ring system of Venus was formed after two Moon-sized object collided hundreds of millions of years ago. The asteroid debree couldn’t reform into a moon, and instead became trapped in a circularized orbit around the planet Venus. Venus is the only Terrestrial planet in our solar system to have developed rings like the outer gas giants, and even though the rings have consolidated their orbit at an equatorial 125 km circular orbit they are visible from almost everywhere on the surface of the planet.

Venus itself has a uninhabitable moon, approximately the same size as our own Moon. This moon has over the eons stabilized the rotation of Venus, and allowed an 28 hour "day." Venus is a wet jungle world, drier then Earth but wetter then Mars or Vega. Scientists have calculated that 65% of Venus is covered by water, and that ninety-three percent of the water on Venus is salt water. Air pressure and Gravity are both approximately 85% that of "normal sea-level" conditions on Earth.

Vega is the Mars analogue planet, dead or dying – just on the border of the inner habitable zone, and close enough to the asteroid belt to guarantee the capture of a number of asteroids from the main belt Vega is about as inhospitable as they come. Vega has no active core, and it has a surface water percentage of 15% liquid water on its surface which is quickly evaporating along with the decaying atmosphere.

For example, photosynthesizing cyanobacteria evolved very early in Earth’s history, perhaps within 50-100 million years of the Earth’s formation. But it took them 3-3.5 billion years for them to rust the planet enough to allow molecular Oxygen to start accumulating in our atmosphere. Only after Oxygen was available in large quantities with its attendant 30-40 fold increase in energy availability did complex multicellular life become possible. It then took ~1 billion years to get from amoebas to humans.

Carl Sagan once published the apparent fact that there is not enough UV light hitting Earth to give it a 21% Oxygen atmosphere in and of itself. But with the presence of chlorophyll, allowing the usage of lower energy photons to manufacture the O2, it becomes possible. Perhaps a blue star with its huge amounts of UV light could have rusted an Earthlike planet a lot sooner and quicker, allowing free O2 to exist in its atmosphere much sooner, thus fostering complex life. Or maybe single cell life forms have some other unknown high energy metabolism source that fosters multicellular life a lot sooner.

I find this interesting because it begs the possibility of skipping the very long period between abiogenesis and multicellular life. With an atmosphere of CO2, and bacteria converting CO2 and HF into Formaldehyde and free Fluorine right from the beginning, we don’t have an Oxygen Catastrophe to wipe out a previous generation of life and create a blank slate. The entire history of life on these particular planets would have the chemicals necessary for indefinite survival and stability already present, and the production of fluorine would cause no problems. This shortens the timescale significantly, especially when we take into account the extra UV radiation, which might be used to life’s advantage rather than being a hindrance to its development.