I'd like to discuss the viability of a "Hollow Earth" type planet.

As I was saying in a different thread, there is a lake under the ocean.
The 'Brine Lake' itself is not as important as the fact it exists.
This got me thinking of all the possible types of planets which could occur in the Universe.
That made me think of a planet inside a planet which made me think of the "Hollow Earth" suggested by Edmond Halley in the late 17th century.
While it has been proven the Earth is not hollow it only proves this planet is not hollow.

This discussion is not intended to argue the Hollow Earth but to discuss ways in which a Hollow Earth type planet might actually form in nature.
If a lake Can occur under the ocean, a planet CAN occur within a planet.
How COULD such a planet occur?

Enceladus (one of Saturn's moons) is mostly covered by fresh, clean ice covering a global ocean.
Europa (a moon of Jupiter) is another.
Evidence even suggests Ganymede (another Jovian moon) has a subsurface ocean of water.
Many people believe there could be life living in these oceans.
If life exists, it means there is a biosphere. An aquatic biosphere but a biosphere all the same.

In the "Hollow Earth" scenario, you have a biosphere existing under a shell.
Essentially a planet within a planet. "Hollow Earth" indicates two distinct biospheres. One on the surface, one below the shell.

Imagine a planet billions of years in the making.
It has a biosphere with a thick atmosphere.
Something happens and the outer edge of the atmosphere thickens.
Slowly, dust accumulates on the surface of this thicker shell and panspermia seeds it with life. A biosphere forms as a new atmosphere slowly accumulates.
Under the shell, life mutates to accommodate the changing conditions.
A planet within a planet. Two separate biospheres.

While we see potential evidence in the ice moons in the solar system water vapor is only one possible reason for a "Hollow Earth" type planet.
For an atmosphere to freeze is pretty common but that freezing usually creates snow which falls to the surface. This means the atmosphere essentially falls to the surface.

However, some really strange stuff occurs naturally in the Universe.
Some relatively short term exposures might cause an instant solidification of some exotic compound at the higher altitudes. Chemically changing the constitution of only a partial layer of the highest layers.
Solidifying them to be later buried by dust and debris.

The Earth has four layers: the solid crust on the outside, the mantle and the outer core and the inner core.
I think it is entirely possible there might be planets in this Universe where an outer crust has formed.
Basically; an outer atmosphere, outer crust, inner atmosphere, inner crust, mantle and inner and outer cores.

Plus, if this were to happen on a geologically active planet it may have volcanoes which penetrate that upper crust depositing even more dust and gas to the outer shell.

Anybody want to chime in?
If yer stuck at home, might be a good way to while away the time while flexing yer brain, lol.
Remember, boredom is a self-inflicted condition.

hmmm a naturally formed dysonsphere...


off the top of my head it would have had to start with an incredibly fast rotation and a very hot core. and that could sling enough material fast enough to create a bubble of cooled matter.

a way of balancing the remaining core at the center of the void to provide heat and light is not appearing at first thought though

Hmm, I hadn't considered an interior cause, interesting.

I was thinking along the lines of a normal planetary biosphere with a shell forming over it then becoming its own biosphere.

Y'know like those ole supernovas which spew out exotic materials which are captured by a neighboring star system changing the chemical composition of things.
A rather short duration event cycle with long lasting changes.
Upper edge of atmosphere cystalizes as a hard shell quickly enough to capture the biosphere inside.

Your centripital force idea has merit too!
In a hot goldilocks zone the surface could be melted solid with material being thrown against the inner side creating a void which then chemically gives rise to a biosphere.
Then if the planet moved away from it star or the star cooled a second biosphere might form on the surface.
... I like it!

yeah but the interior biosphere still needs light and heat how do we get that?

a constructed dysonsphere is built around a sun

Yeah, I know who Freeman Dyson was and the concept of mega-scale engineering of harnessing a star system. There's also a Dyson Ring (think Ringworld, Halo) and a Dyson Swarm.



Heat might not be a problem with a planet's core. If it has a molten core.

Light could be a chemical reaction (think glow sticks) or a bio-chemical reaction (think fireflies).

Plus gotta remember even here on this planet there are organisms thriving in caves and the oceans in darkness. There is even anaerobic life which needs no oxygen. (think caves and black smokers in the oceans)
These are all 1:1 ratio of reality. We know they exist on this planet and since we have never looked at any other planet the same way, we don't know so it remains a 1:1 ratio until we confirm other planets do not have such lifeforms.

Someone wrote a book about that idea, a known author, I think it was maybe Robin Cook?
It was actually a fascinating book. Or was it Stephen King?

In any case, it is mostly discussed as a more energetic place, possibly with a few physical things, but not 3D, 5D.
Allegedly it's located in the US, there's stories of there being an entrance to it in Mt Shasta, n. California, where weird phenomenon are often seen.

In any case, my views knowledge & experience doesn't fit on this forum :)

Ah, but everyone is welcome to comment on it.

Hollow Earth

Ludvig Holberg's 1741 novel Nicolai Klimii iter subterraneum (Niels Klim's Underground Travels)

Giacomo Casanova's 1788 Icosaméron, a 5-volume, 1,800-page story

I haven't read those (thanx wiki) but I have read Edgar Rice Burroughs seven-novel "Pellucidar" series and watched a lot of movies and shows either based on the concept or having it as a plot element/setting.

To clarify, the intent of this discussion is not to confirm or deny Hollow Earth as pertaining to Earth. That has been done to death.

This thread is to inspire logical imagination in determining whether a "Hollow Planet" with two distinct yet separate biospheres might be possible naturally.
Since it is based on logic but purely speculation everyone has authority to comment. Everybody is qualified.

Its a mental exercise for something to do. Something different to think about. There is no test and you won't be graded. Its for fun.
Based on logic and reason.

If you say a space dragon made it, its probably not going to make sense.
But, if you can reason how space dragons might exist who could make it with reason and logic based on current mankind understanding of natural phenomenon, go for it.

Lake under the ocean exists, a 1:1 ratio of fact because we know they exist.
Lake under the ocean exists, a 1:0 ratio of fact means they exist but we didn't know it.
Space dragons exist, a 0:1 ratio of fact because we don't know if space dragons exist.
Space dragons exist, a 0:0 ratio of fact means space dragons can not exist.

The goal is to find as many 1:1 facts to support a Hollow Planet as we can
or find as many 1:1 ratios of fact to deny a Hollow Planet.
Get it?