The Globe and Mail asked readers to pose questions for Chris Hadfield, Roberta Bondar and Marc Garneau - three Canadian astronauts that have travelled aboard the space shuttle. Questions were selected and have been submitted to Mr. Hadfield, Ms. Bondar and Mr. Garneau. Here are some of their answers. More will appear in this space over the coming days.
Devon Brooks asks: Do you have any insights as to what the mid-term future (10 to 20 years) will look like for the international space program with huge government cutbacks and a shaky world economy? Is space exploration going to become a private enterprise in the future?
Chris Hadfield: Devon - space exploration is almost exclusively a private enterprise, with equipment built by private companies, for profit, across Canada and around the world. The key, as you mention, is what proportion and amount is bought from those companies by the government. In the US and Canada government funding for research and space exploration has been steady. My best guess is that it will continue that way, especially when balanced across the globe. Companies like SpaceX and Virgin Galactic are some of the first to seek significant funding from other sources, primarily tourism to this point. But step-by-step, invention-by-invention, the price will come down, safety levels will rise, and it will become an ever-more viable commercial business.
Don Gibson asks: What does re-entry feel like? Is it rough? Are you pressed into your seat or pushed out?
Chris Hadfield: Don - re-entry begins by firing our small orbital engines to slow down a tiny bit. That lowers our orbit just into the upper atmosphere, and then we let friction with the air take over. At the start we're still weightless, but as the air slows us down more and more it is like falling into jello, a steadily increasing deceleration. The force builds up, and squishes us into our seat - smoothly in the Shuttle about 3G down into the floor, in roughly in the Soyuz about 4G through our chest into the seat backs. The friction is so high that it gets to 3000 C on the outside skin of the spaceship.
Julian Gray asks: For the men in the sky beyond I'd like to ask how they feel about humanity compared to before they saw the Earth in Orbit?
Chris Hadfield: Julian - seeing the Earth from space gave me a renewed and strengthened sense of responsibility. We all live on the same ship, and its life support system is razor-thin; a wisp of air and water between rock and eternity. I am very heartened that 16 leading nations of the world have sent emissaries to see the world from beyond the sky, to live on the International Space Station, to use that platform to better understand our planet and ourselves, and to then return and share that perspective. So many of our daily squabbles seem diminished in comparison. By seeing our World as one connected place we can better understand what we are doing, right and wrong, and where to best focus our energies for the future.
Paul Lowe asks: What is the strangest out the ordinary observation you have witnessed in space, that is truly unexplainable.
Chris Hadfield: Paul - for me, the hardest thing to try and explain is the existence of our Earth. A fragile, jewel-like orb glowing and thriving in the middle of unending dark dead emptiness. Until our best telescopes find another one, our Earth is a wonderfully unique mystery.
Nicholas Cashmore of Milton, Ont. asks: Do you think there is life in our universe? What do you think they would like and what would we have to learn from them?
Chris Hadfield: Nicholas - we don't know for sure, but I think there is life beyond Earth, yes. Just a few hundred years ago we used to think the universe revolved around us, but the more we have explored the more we have found that Earth is simply one planet of a countless number. We have now seen over 1400 planets around other stars. To think that life is unique to Earth seems an extension of self-important ignorance. To try and help answer that question, Canada is part of a scientific research rover headed to Mars this Fall to look for evidence of life.
Michael Price of Vancouver asks: Why has America lost its nerve in space? Why is it ceding superiority to the Russians, the Chinese, the Indians, and the Japanese?
Chris Hadfield: Michael: It hasn't. Next year I am going to ride a rocketship from a standing start to 28,000 km/hr in 9 minutes, and then live on an International Space Station orbiting the Earth 16 times a day for 6 months. That takes nerve. Your follow-on question completely depends on your definition of superiority, but I think that a quick look at the ISS and planetary probes will show tremendous current proven capability. The Shuttle was a very capable and visible vehicle, but it was never the only vehicle.
Mahesh Yadav asks: Can you see the stars with the naked eye in the black sky in the direction opposite to the sun during the space walk or through the windows of space shuttle or space station? If so, how good is the visibility as compared to ground-based dark sky observation?
Chris Hadfield: Mahesh: yes, you can, but like night vision on Earth you have to wait long enough for your eyes to adapt, like walking from a sunny day into a dark theatre. Once your eyes get adjusted, the view is fantastic - a crystal clear view of the Universe, where the stars don't twinkle with no atmosphere in the way.
John Kable of London, Ont. asks: What type(s) of navigational software do you use on the space station and shuttle? Are they a NASA product, or commercially produced? And how about star maps? Also NASA, or commercial products? I know that is more than one question, but all part of the same overall question.
Chris Hadfield: John: We use several types, depending on flight phase: gyroscopes and accelerometers, GPS, star trackers, optical sights, radar, TACAN, pitot-static sensors and ground tracking. The GPS and TACAN are commercial/gov't, the rest are specifically built/used for the Shuttle.
Claire Eagle asks: Public interest in space has notoriously declined in the last few decades. Do you see this picking up, with increased R&D, exploration, and funding to come in the future? Or do you think that politically, we will remain more focused on problems on earth? Also, do you believe that public perception of nuclear energy and recent growing distaste for it will impact future space exploration at all?
Chris Hadfield: Claire: I disagree. Nearly 1,000,000 people came to Florida to watch the last Shuttle launch - that is a direct indication of interest! The facts are that public and government support has been steady. Remember that even in the absolute heyday of early spaceflight, the Apollo Program and after the 1st Moon landing, public attention naturally wandered. The last 2 Apollo missions were cancelled, and even by Apollo 13 interest had dropped way off. There's a difference between space exploration and space entertainment; we are not doing it to amuse and entertain, though sometimes exciting things catch the public's attention. The key is to continue doing good work, to keep setting barely-attainable goals, and to keep expanding our understanding of the universe around us.
Your second question is a key issue - power generation. To launch from Earth and to explore require a compact and efficient power source, and nuclear energy is an option. In order to use any power source we need to be efficient, and to guarantee safety. No system is perfect and all have trade-offs, just like on Earth. Public perception is important, and so is good engineering. But the impact of nuclear power is minimal on space exploration - we seldom use any form of it, and never for human spaceflight.
John Read of Halifax, N.S. asks: Mr. Hadfield, SpaceX, Dream Chaser, Boeing and Blue Origin recently received funding to construct vehicles that will carry astronauts to the International Space Station. Which of these upcoming private space launch systems are you most anticipating and why?
Chris Hadfield: John - I am most anticipating watching Canada's new astronauts, David Saint-Jacques and Jeremy Hansen, as they and other astronauts work with the manufacturers to make these initial designs operational. All vehicle designs are strong contenders, and it will be great to see the final result fly. What we need is simple, reliable and safe space transportation, and what we have learned from the Shuttle, Soyuz, Apollo and other spaceships will be invaluable in getting there.
John Thurston asks: Why is heat only a problem on re-entry and not on liftoff?
Chris Hadfield: John - because during launch the engines push us straight up until we are above the air, and only then do we accelerate to orbital speed of 8 km/s, up in the vacuum of space.
It's different on re-entry: we use the small orbital engines to slow down a tiny bit and thus descend into the atmosphere, and then use friction from the air to slow down.
That saves us having to bring fuel to slow down, but it creates a very high temperature around the vehicle, near 3000 C.
Humera Jabir asks: I would like to ask the astronauts how going to space impacted any religious or personal beliefs they may have? Big question, but I would just like to know what comes to mind for them.
Marc Garneau: This is a personal question and every astronaut will answer it differently.
Like most humans, I have sometimes struggled with my faith. At certain moments, it has been strong and at others, I have experienced doubt.
When you are strapped into the shuttle and waiting for it to launch, you certainly reflect on your faith and as with all intense moments of this kind, you hope that God is with you because you really need him.
I have to say that when I arrived in space after the wild ride that took me there and first looked down on the majesty and the beauty of planet Earth, I experienced a quiet but very strong conviction that God does exist.
Intense experiences can open your mind and make you see things differently. Although I am basically the same person now as I was before my first spaceflight, I have also been altered in important ways by the experience. I see the world and indeed life itself differently.
Corey Richard asks: Mr. Hadfield, you will be doing your third space flight. How do astronauts mentally prepare for their first space flight?
Chris Hadfield: Corey: Through realistic visualization and preparation. We study every detail, mentally work our way through each step and misstep, and build a plan that will work, no matter what goes wrong. Then we practice it over and over in simulators. That gives us the calm and confidence and ability to launch.
Ian Martin of Elora, Ont. asks: What is your view on the costs/benefits of manned space flight? Can it be justified? It seems to me that there are very few big science questions that cannot be answered by unmanned space flight, which would be much cheaper in terms of both financial and energy costs as no life support systems would need to be lifted.
Marc Garneau: Thanks Ian. When the answer to a scientific question related to space can be provided by an instrument or a robot, then we should build that instrument or robot because it will cost less and no lives will be at risk.
Once in a while however, we may decide that we need to send humans to space because there is a strong public will to do so, or because a human is more capable than an instrument or robot for certain very complex tasks. If we make that decision, we accept the greater cost and the possibility of loss of life - never an easy decision.
As robots become more sophisticated, there may be fewer arguments for sending humans to space. Having said that, a robot will never be able to express its emotions as it lands on another planet or when it orbits our own planet earth. Machines don't inspire us like humans do (although I have to admit as an engineer that I'm very inspired by those who design and build the machines).
Finally, without trying to sound boastful, I have looked into the eyes of too many young people not to know that astronauts capture their imaginations as very little else does. A complicated answer to a complicated question.
Kenyon Lee, age 5, asks: Mr. Hadfield, my Daddy met you once and bought you lunch in the Vancouver International Airport. We have the picture you gave him framed on our wall and we love to go to the Space Center in Vancouver. There is so much cool stuff in space. What is your favourite cool space thing? My favourite is the pictures we see of the earth from space. I would like to met you one day like my Daddy did.
Chris Hadfield: Thank you. Kenyon, my favourite cool space thing is doing a spacewalk. To be floating free in your spacesuit, alone in the universe, holding on with one hand watching the world roll by in all its glory is a wonderful human experience. I would like to meet you too!
Send your questions to email@example.com with "Ask an astronaut" as the subject. A selection will be answered by Canadian space pioneers during the final mission of the space shuttle program.