@Setanta,
Setanta wrote:
Here is a relief map of Mars:
On the left there are four gargantuan volcanoes. The three that run south-southwest to north-northeast sit atop the Tharsis plateau. This is now generally considered to have been a gigantic magma dome. The volcano in the center of that line of three is Pavonis Mons (Peacock Mountain). The southern rim of its caldera sits on the equator. To the right, you will see a feature known as the Hellas Planitia. The name is misleading, it is not simply a plain, it is an impact crater. It is oblong from east to west because the object, a planetisimal about 125 miles in diameter, came in, probably very fast and low. Most of the ejecta was thrown to the west, suggesting the speed, and the oblong nature of the impact crater suggests that it came in low. Below is a more detailed map of the Hellas basin:
Note the Hellespontus Montes to the west, while there are no similar mountains to the east. That provides more evidence that the object came in low and fast. Many, but by no means all planetologists studying think that the magma dome which created the Tharsis plateau was caused by that impact. Enough scientists consider Thatsis to have been caused by a magma dome that most of them refer to it as the Tharsis bulge. Whether or not it was caused by the planetisimal which created the Hellas basin is less certain.
The point is that whatever caused the eruption of the four mightiest volcanoes in this star system, that very likely explains why volcanism has ended on Mars. With no hot core, there will not be any "hotter" magnetic field around the planet because there is no longer a mechanism to cause such a magnetic field.
Have you watched any of the Electric Universe videos on youtube explaining how surface features of Mars could be the result of powerful electrical activity that carved the surface like a plasma torch? It sounds far-fetched, but if you think about the early solar system as a hot planetary cloud/disk, then a such a cloud would exhibit a lot of internal lightning, the way a thunder storm involves a lot of lighting strikes between clouds as they condense and shift turbulently. Eventually, as the clouds of the solar system would condense into planetary bodies, the space between them would clear of ions and dust so that the main communication of energy would take the form of light passing through clear skies, along with some light solar wind. However, the further back you go into the past, the thicker the solar wind and electrical transmissions/current running through it, and the more diffuse and scattered the light would be by the ionized cloud/material permeating the entire solar system.
If hot planetary (ionized) gas can condense into magma and gradually cool into violent volcanic activity venting energy out through the cooling crust, the core may have cooled relatively quickly, but through that process, veins of extremophiles could have emerged and evolved into organism chains that capture solar energy and pass it down through the ground to pockets of water that are insulated enough to foster aquatic life. These organics, in turn, could die and sink down to form more energy-dense sludge, which in turn could be compressed until it begins a sort of pyrolysis, which releases the energy as heat, which then builds up because it is insulated by all the material around it.
In short, I think it is possible for a solar-energy 'bridge' to form as a hot planet cools, and then for that bridge to continue transmitting solar energy underground where it can build up to form a nascent molten core and corresponding magnetic field. The more the core and magnetic field grow, the more protection there is for life on the surface to emerge and evolve. The thicker the atmosphere can grow without being stripped away by solar wind, the more solar wind can be captured and settle as dust, which over huge periods of geological time can increase the overall mass and thus gravity of the planet, which in turn causes the atmosphere to thicken and more heat to build up from greenhouse gases that are retained.
