This is an open challenge. Provide me with any evidence that disproves round earth and I'll give an explanation using mathematics and physics on why it is wrong.
The only assumption I am going to make is that the mathematics and physics I have been taught is true.
Serious one - At high alt, right on boundary of space.
What stops small particles escaping? they must be colliding, moving about so whats stopping them just moving that little bit more over that line and floating off?
Could that be happening but they are getting replaced by inbound particles kind of a constant balancing act ?
Mars got me thinking about this.
We are losing our atmosphere for many reasons. Mainly, solar flares scrape away the upper part of the atmosphere often. Secondly, there are few air molecules which move faster than the escape velocity.
The speeds of the molecules are stastically governed by Maxwell-Boltzmann equation. Given below is a plot known as Maxwell Distribution Curve.
X-axis = speed
Y-axis = probability of a gas having that speed
Area under the curve from [a,b] = total number of molecules having speed between [a,b]
The above picture gives you the total number of molecules with speed <X> . The area under any section of the curve gives you the number of molecules.
While the majority of the molecules have speeds which lie in the center, there are few (tiny bit of them) which have very high velocities. These escape the earth every day.
A tiny fraction of the gasses escape. While there are processes which remove the gas from the atmosphere, there are processes which add new gas to the atmosphere: meteorites? There are 60,000 tons of material added to the earth from meteorites every year. Most of these get burnt up in the atmosphere due to friction (they are traveling pretty fast and they heat up as they decelerate through the atmosphere). Some of them don't get burnt up and they hit the ground creating large craters.
Russian Meteor Explosion:
Our estimates indicate that it would take trillions of years for all the hydrogen in the atmosphere to be depleted. Why am I talking about hydrogen instead of the air as a whole? Hydrogen is the lightest element and it has the highest chance of leaving the earth. The velocity of the air molecules is a function of the temperature and molecular mass. If hydrogen depletes slowly, then other gasses are going to deplete even slower.
If you were on a more silly note, the earth gravity keeps the air together. The air is more dense near the surface and its density decreases as you go higher. The earth's gravity is strong enough to retain majority of its atmosphere.
Mars has a very dense atmosphere. Relatively lighter elements such as CO2 are thought to be removed by the solar winds. Work is still in progress. There are a dozen rovers on the surface of the Mars currently investigating. We don't know everything about Mars yet.
Atmospheric escape:
https://en.wikipedia.org/wiki/Atmospheric_escapeMaxwell's Distribution:
http://ef.engr.utk.edu/hyperphysics/hbase/Kinetic/kintem.htmlWe lose 50,000 tons of mass every year (good read):
https://scitechdaily.com/earth-loses-50000-tonnes-of-mass-every-year/