Earth with Same Size as Sun

[Cookie Monster]

What are you talking about? If the fusion starts the core of the planet, soon it will turn into a burning ball if rock and metal.. Do you know that the plasma at the core of the sun is the densest material in the solar system. It it so dense that a photon takes nearly a 100,000 years to leave the core while it takes only 8 minutes to reach the Earth from the Sun.. so all these rocks will melt or be glowing like incandescent bulb emitting radians like anything

Could u plz show me a rocky star...anywhere in the universe? All stars(not including the neutron stars) I've read about so far are gasseous(mainly made up of hydrogen and helium).

The reason why it takes so long for a photon to leave the sun is bcuz it is constantly being emitted, absorbed, emitted, and so on...until it finally through a random series of that emission/absorption ends up in the photosphere of the sun.

Also I never said that plasma isn't dense. There are neutron stars that are even denser made up entirely of neutrons. This doesn't mean a rocky planet can turn into a star by its sheer size.

If the fusion starts the core of the planet, soon it will turn into a burning ball if rock and metal

When stars fuse hydrogen to helium and so on...once they get to iron, fusing anything after iron runs a net energy deficit. This means fusion can no longer fight off the immense gravity and a super nova occurs. Now applying this principle in case of earth the size of the sun...if fusion started at the core of earth(while it was the size of the sun)...it will soon become unsustainable bcuz the majority of earth's core is made up of iron. For a star to be a star it doesn't only need enough mass to start fusion, it also needs a steady supply of elements it can fuse to sustain itself.

 

[RIP Pak LAW]

Though the possibility of life on such a massive planet can't be ruled out entirely...however it would be very unlikely for anything other than bacteria and other microscopic creatures to exist on this planet. The sheer gravity of such a planet would make life of bigger creatures difficult and if they ever do evolve, they will probably die out.

Also if the Sun is enlarged proportionally, then that hypothetical earth would also have to be really far away from that sun than it currently is...otherwise it would be scorched like Mercury is. Such a massive sun would also die out quickly...relatively speaking. This means life wouldn't have enough time to evolve complexity.

According to Miller-Urey experiment and as per the current theories of how life evolved on earth...it probably first happened in deep oceans around thermal vents. If earth was the size of the sun, then the huge gravity of earth would mean that the water in deep oceans would be under immense pressure, which might turn it into ice-VII and life may never happen.

Summed up well.

Rocky planets can't be that big. Else it would had been a gas giant. Also hypothetically speaking, if that would had been the case, gravity would had been immense for human like us to evolve and stand the way we do unless that planet would be occupied with super giant humans.