And all agreed humanity will eventually be on Mars with regular flights between Earth and the Red Planet, mainly due to the great interest of private entrepreneurs, such as Elon Musk and his SpaceX.
Musk believes he can land a small party in Mars in mid-2020.
Aerospace engineer Dr Thomas, the first Australian astronaut in space, said that people will have a permanent base on Mars in 50 years.
"We will have colonies on Mars," he said.
Thomas flew to Space Shuttle Endeavour in 1996, and then spent 141 days in Space at the space station before he ended his space trip to Shadtle Discovery in 2001 at the International Space Station, where he completed a spatial walk in half an hour.
However, he said that people should never look to Mars as a reserve option for the Earth.
"Mars is a harsh environment," he told NASA's astronaut audience We will Martians: our future on the red planet, moderated by Professor Brian Greene.
"There will never be another country," he said.
He said that Mars did not give mankind the opportunity to forget the Earth and focus only on the new settlement on Mars.
"I think this is an arrogant hubris," he said.
The meeting addressed various aspects of simulated flying to Mars, including the trip itself and the various ways in which the space vehicle could return, before the audience looked at the Martian craters and cracks – about five kilometers deep through 3D glasses.
Geolog dr. Jon Clarke works on simulated Mars camps in Utah deserts and Antarctic frostbite conditions.
Professor Clarke and Professor Christine Charles talked about how the shortest trip to Mars could last for three to four months if electricity was used, but it was normal to be a 16-month return trip.
"It takes a lot of fuel to get off the ground and enter the universe," said Professor Charles, adding that future travel might not be using a conventional rocket flight.
One of the options that was explored was an elevator for a space of 36,000 kilometers, which would take the crew to an elevator that would not require so much fuel to leave the earth's atmosphere.
"There is a big problem at the moment," she said.
"How to build something that is 36,000 kilometers long."
The concept has already been tested with small prototypes, she said.
"We are also testing the concept of one of these electric (plasma) motors with one of these nano-satellites," she said.
"The fact that the private sector is involved in this, I really think it has the ability to make progress."
Dr. Thomas said that this method could work "in the future," but a more sophisticated conventional drive to launch a rocket would bring the first people to Mars.
Science, however, could develop a series of hydrogen fuel that could be used to return from Mars.
"We know on the surface of the moon in some deep craters that there is a glacier of the crater," he said.
"It can be decomposed and made hydrogen and oxygen that can be used for breathing and fuels."
Professor Greene said that sending teams with robots is significantly cheaper than sending space teams to people.
"We can run 1000 robots for the same costs as for two astronauts," asked Professor Greene.
"Why not send robots?"
Professor Cagle said that robots – including advances in artificial intelligence – did not have the capacity to achieve the goal
"Robots have no curiosity," she said.
"You have this with people."
Professor Reynolds warned that rescuing boredom on long space flights is an important part of a successful mission to Mars.
Dr. Thomas said that this is a very serious issue in long space flights.
"In the first days of Russian missions with both cosmonauts there was a complete breakdown in the communication of the crew," he said.
"They did not speak and both acted as if there was no other cosmonaut there.
Tony Moore is a senior rapporteur for the Brisbane Times