Extract from ABC News
Congratulations, you've won a ticket to Mars.
You may have to wait a while before you can get on a flight. Launch opportunities only come around every couple of years when Earth and Mars line up.
Your first challenge will be to actually get off Earth.
That's not as easy as it sounds (we're still ironing out a few technical details with our spacecraft).
It's a hell of a ride. To break free of Earth's gravitational pull, you need to reach escape velocity — that's 40,000 kilometres per hour, or 11km per second.
That means you'll have to train yourself to tolerate high g-forces.
During take-off, astronauts experience at least three times the gravitational (g) force of Earth (most humans can tolerate up to 5gs before passing out), and up to 8gs on re-entry.
Once you've escaped Earth's pull, you'll feel weightless and your journey begins.
Surviving the journey
Your trip to Mars will take seven months (that's taking the shortest possible route cruising at about 78,000 kph).
In that time you will share an 8 by 11-metre space with at least four people (if you found COVID-19 lockdowns challenging, this might not be the flight for you).
Unfortunately, the view out the windows won't be great. Apart from when you are first leaving Earth or just arriving at Mars, you won't see much, not even stars.
That's because at least one side of your spacecraft will be illuminated by the Sun at all times, says Jonti Horner, an astronomer at the University of Southern Queensland.
"If the Sun is anywhere in your field of view or anything in your field of view is illuminated by sunlight, that will be so much brighter than the stars," he says.
As you get further and further away from Earth, you will lose real-time communication.
By the time you reach Mars there will be a delay of around 12 minutes, so you and the other passengers will need to work together if there is an emergency.
One of the greatest threats you may experience is a solar flare spewing radiation out into space.
Unlike astronauts on the International Space Station, you are not protected by Earth's magnetic field, so hopefully your spacecraft has a radiation panic room you can hunker down in for two or three days until the threat passes.
And while weightlessness makes great social media posts, it plays havoc on your body.
One approach to deal with this is to have a spacecraft that rotates to simulate the effects of gravity like they had in The Martian (unfortunately our spacecraft is much smaller, so it would spin a lot faster).
You may also need to do exercises to keep you on your toes. Literally.
Spending a lot of time in little to no gravity without exercise not only causes problems with bone density and muscle mass, it messes with the human senses, says Gordon Waddington, whose team at the University of Canberra is developing exercises to help you work out where your body is in space.
"One of the really critical things that's going to go on over [the journey] is the way your brain listens to movement is going to change, and your brain's model of your body is going to change," Professor Waddington says.
Welcome to Mars!
You should start getting some good photos of Mars by the time you're about 2.2 million kilometres away.
The landscape looks red thanks to the iron oxide in the soil. And you may see polar ice caps and huge volcanoes and canyons that put anything on Earth to shame.
But make no mistake: Mars is a very hostile place.
It has a very thin atmosphere, which is mainly made up of carbon dioxide.
It's also very cold — the average temperature on Mars is -63 degrees Celsius — although this varies from location, time of day and season (if you're lucky it can get up to 20C in summer).
To get an idea of conditions at Gale Crater near the equator, check out Curiosity rover's daily weather report.
And the air pressure is very low. The good news is it doesn't feel windy even when it's blowing a gale, the bad news is that the air pressure is so low that all the water in your saliva, tears, skin and lungs will evaporate immediately if you don't have a spacesuit on.
It's also why the surface of Mars is very dry — although there is evidence of vast rivers and lakes in the past, water on Mars today is in lakes under ice at the poles, as well as some vapour in the atmosphere.
And, at certain times of the Martian year (usually the southern hemisphere summer when Mars is closest to the Sun), the entire planet can be swamped by a dust storm.
The dust is so fine and dry that it's abrasive, and it will play havoc with anything that is solar powered (look what happened to the Opportunity rover).But the blue sunsets are spectacular.
"The sunsets look a lot bluer than they do on Earth because the dust in Mars's atmosphere is much [finer]," Professor Horner says.
And then there's the radiation. Mars doesn't have a magnetic field, so it gets blasted by the solar wind.
Levels of radiation vary from location to location, but even in the lowlands where the atmosphere is at its thickest, you'll get hit by around 273 millisieverts a day.
That's right at the upper end of what an astronaut onboard the ISS is exposed to (unless there's a solar flare), and well above what you are exposed to on Earth.
Don't forget to keep in mind you will be living in this environment for two Earth years (did we mention that one Mars' year is the equivalent of two Earth years in the brochure?) — so it all adds up.
So, you might be wondering by now about how you're going to survive …
Your home won't have much of a view
We hope you like the idea of living underground.
There may not be much of a view, but scientists believe it's the best way to reduce your risks from radiation, bombardment by micrometeorites, extreme temperatures and dust storms.
You could either dig your own shelter, or use what nature provides.
It appears that Mars has hollowed-out caves created by lava from volcanic eruptions billions of years ago, says David Flannery of the Queensland University of Technology.
With little tectonic activity on the Red Planet and weaker gravity than Earth, these structures have remained intact since then. albeit with a few cave-ins that give them away from space.
"When we see chains of sky lights, we're pretty sure we're looking at a lava tube complex," Dr Flannery says.
"We can see some real whoppers."
But if you prefer comfort over rustic ambience and you like living in a habitat that is structurally sound, then a custom-built bunker may be more your style.
If you do decide to venture outside, you'll need specially designed suits that can withstand radiation — remember that radiation breaks down anything made out of carbon, and that includes synthetic materials. (We've just sent some space suit materials to Mars to see how they survive.)
However, it might be safer if you send out an army of robots and drones to do the work for you.
Robots could also be used to retrieve items left behind by humans or for mundane maintenance or servicing, says Navinda Kottege, whose team at the CSIRO is developing artificial intelligence software for autonomous robots.
"Hopefully human time and attention on somewhere like Mars would be reserved for science and discovery," Dr Kottege says.
We've been sending robots to Mars for a while now, but you'll need something that can travel over all terrain. Drones would be cool (we'll be taking one of those for a test run shortly).
What about food and water?
Unless you're a fan of reconstituted space food for the duration of your stay, you'll also need to grow your own high-nutrient food.
You might want to try to grow potatoes in your underground bunker, like Mark Watney (played by Matt Damon) did in The Martian.
Experiments show some types of potatoes can grow in highly salty conditions similar to the dirt on Mars, but we can't guarantee how safe they will be to eat.
The soil contains toxic chemicals called perchlorates, as well as heavy metals such as lead, arsenic and mercury.
And plonking poo on your potatoes could increase your risk of gastro or some other disease, which could make life very unpleasant 200 million km from home.
We have grown a few plants on the ISS such as microgreens, radishes and even wheat.
But one of the big problems is disease, says Adam Frew, an ecologist at the University of Southern Queensland.
Dr Frew studies plant microbiomes — the bacteria and fungi that co-exist with plants — to see if it's possible to synthesise hardier plants that could tolerate the extremes of space.
"We think that in space, plants struggle to establish the correct microbiome that they would need," he says.
In the future, you might find synthesised mung beans and potatoes on the menu.
If you do grow some plants, they're going to need water. There could be a few options here worth exploring.
You could recycle the water you brought to Mars, you could extract water from the vapour in the atmosphere, or you might be able to tap into the potential sources of water trapped in soil beneath the surface or lakes under the ice caps.
We'll let you know if any of these options are viable sometime in the future.
And of course, you're going to need oxygen. Not only so you can breathe, but to blast off Mars when the time comes to go home.
Going home
It might be possible to extract oxygen from the carbon dioxide in the atmosphere (we're about to test that).
If you have water, not only can you make oxygen, you might be able to make rocket fuel.
Here's a demo from Catalyst of how this might work:
Technically, it should be easier to take off from Mars than it is from Earth because of the lower gravity, but we haven't had a chance to try it yet.
The lead-up to your departure will coincide with the three-quarter mark of your mission.
You might notice that you or some of your fellow travellers get a bit tetchy around this time — this is a pretty normal phenomenon that can affect how you work as a team.
But you don't want to be left behind (look what happened to Mark Watney in the Martian) — otherwise you'll be on Mars for another two years, so try to smooth things over with a sense of humour.
All going well and you survive the seven-month return journey and the descent through Earth's atmosphere (remember those g-forces), you'll be back on Earth a little bit more than three years after you left.
To put that in perspective, the longest anyone has spent in space in one stint is 14 and a half months on the now defunct Mir space station.
However, you will have been exposed to higher levels of radiation and been much more vulnerable to the whims of the Sun than they were.
To be honest, we're not sure what impact that will have on your body.
If you're still interested in going, we'll get back to you with an update in 2030.
In the meantime ... watch Catalyst's two-part special Mars: Our Second Home? on Tuesday, February 23 and Tuesday, March 2 at 8.30pm.
In episode 1, astrophysicist Professor Tamara Davis and astronomer Greg Quicke meet the Australian scientists on a mission to solve the many challenges of putting people on the Red Planet.
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