What evidence of two way space travel would you accept?
Why do you avoid answering this? You have been asked a dozen times and never give an answer. Can you not think of ANYTHING?
I haven't avoided that question. If you study my website you find that I support
one way, high speed space trips putting satellites in orbits in space at various altitudes. I am a small shareholder of one such company since many years. We send anything into orbits. But not humans.
The problem is the return trip of a spacecraft, reduction of altitude and the associated reduction of speed for landing on Earth, a.k.a. braking.
Our friends Gagarin and Glenn suggested 1961/2 that they used retro-rockets to reduce altitude even if their spacecrafts lacked fuel for it.
And then the altitude was reduced and they started entering, at a certain angle, the atmosphere , which is very thin at the top and denser at ground level.
It is suggested that a force developed when you penetrated the atmosphere - friction drag - which is a function the local speed of the spacecraft and the local density of the air.
There doesn't exist any scientific method to calculate that variable force and resulting trajectory of the spacecraft attempting to land on Earth after a trip in space. You can ask any university teaching astronautics and none can provide the answer.
Simple calculations of the
energy (J) required to slow down any spacecraft for landing shows that that energy would heat up the spacecraft 40000 C, i.e. it would vaporize in smoke at once. 99.99% of all meteorites dropping down from the Universe end up like it.
But Buzz, PhD, invented a fantastic 'heat shield' that absorbed that energy, bla, bla, bla. The details are top secret. National security, you know!
I always feel sorry for people having spent plenty time and money to become astronautic scientists that then must lie that re-entries from space is easy, bla, bla. to be employed by NASA, ESA, SpaceX and similar criminal organizations.
Mainstream media are not interested. They support the criminals. It is just a question of money.