Allow me to read to you an excerpt from the lead editorial of the 1997 Summer Issue of Space Times magazine titled "Let's Go to Mars".

"Mars is waiting for us. A big juicy planet with the possibility of water and the possibility of life. Out there looking beautiful and waiting for the humans to come and visit. I think that it's a little strange that colonization of Mars is such an obvious next step in the exploration of our universe and we are not recognizing it"

Yeah I wrote that when I was 17 years old...

(Intro Segment)

I was then, and still am, a bit of a Mars exploration junkie. You are, after all, looking at a founding member of the Mars society, and one of the first websites that I created, when I was in high school was called "Hanks Guide to Mars Exploration".

Let's be honest. Ever since man first set foot on the moon in 1972 a manned mission to Mars has been the holy grail of space exploration. It's been 40 years! And I've got more bad news for you, because at best, a manned mission to Mars is at least 20 more years away, and at worst, and I mean this as the very worst, it may not even happen within my lifetime. Balls to that!

To better understand why it such a potentially awesome thing isn't even in the planning stages right now let's examine the 4 biggest challenges we face for a manned mission to Mars.

Number 1: How to get there.
Number 2: The risks involved.
Number 3: The money.
Number 4: The why.

So number 1, how do we get there. To begin with, we need a new spacecraft and we need a new booster vehicle. Now it's important to note that these are two different things - the booster gets you out of Earth and the spacecraft gets you from one place to another in space.

In 2005 NASA's Constellation program was revised to allow for the creation of a new spacecraft. Using a planned Orion Spacecraft, Altair Lunar Lander, and Aries booster rockets modelled after the successful Saturn V rockets that launched Apollo the Constellation program aimed for a 2019 return to the Moon followed by a manned trip to mars sometime after 2030.

But then, in 2010, the Obama administration announced a new spaceflight program that had similar goals but totally scrapped the moon thing. The new spacecraft now being designed calls for a new heavy lift launch vehicle to be completed later this decade that can be used for either crew or cargo. The SLS, which will someday have a cooler name than that, actually uses engines designed for the space shuttle, combined with a liquid hydrogen and liquid oxygen propulsion system. For manned missions, the SLS will carry the Orion multipurpose crew vehicle, which can hold between 2 and 4 people and for cargo missions it will have a lift capacity of up to 130 metric tonnes. 

In announcing the project last year, President Obama said that the SLS would allow for missions to asteroids by 2025, and Mars sometimes in the 2030s. This is great, and everything, but it's not really a plan. The fact is nobody really knows how the SLS would get us to Mars or anywhere for that matter.

I recently got to talk to Mars Society founder Robert Zubrin who was one of my heroes when I was in high school and wrote the AMAZING 1996 book The Case For Mars. And he pointed out the lack of a defined goal for the SLS is a serious problem. He added that the Apollo program succeeded because the Saturn V rockets were developed specifically to go to the moon.

The Mars Society's full of really good ideas for how to get to Mars. One of them, called the Mars Direct Program, calls for utilizing 2 launch windows that occur 26 months apart. The first launch would involve the unmanned Earth Return Vehicle, the ERV, which would land on Mars way before astronauts get there and basically set up on Mars a rocket fuel making facility. 26 months later the Manned Habitat would be launch along with a second ERV, and the reason for that second ERV is basically as a backup. The second ERV would go much slower than the manned crew vehicle so the crew would land, make sure that the first ERV was functional, and if not, they could call down the second ERV, which would land in their vicinity.

You really don't want to arrive, on Mars, and then find out that your ride home is totally busted.

More recently Zubrin has promoted a similar strategy but this time using vehicles that are created by the private firm SpaceX. Using a souped up version of a current SpaceX rocket called the Falcon Heavy - I just have to say here for a second that they are way better at naming rockets than NASA is. It uses a conventional Hydrogen-Oxygen booster, and has a crew vehicle, called the Dragon, and Zubrin, for this strategy, envisions three separate launches.

So in this scenario the ride home stays in orbit around the red planet while the astronauts work for a year and a half and then use an ascent vehicle to rendezvous with it and fly home. It sounds a little bit complicated but Zubrin thinks that using a private firm would drastically speed up the time-line for a Mars mission. In fact, he thinks as soon as 2016, which seems a little optimistic to me.

Challenge #2: The Human Risks

So even if we can get a good ship to get astronauts to the red planet, there are some, you know, psychological and also some physical risks that these people will be taking. Your number 1 and number 2 here are radiation and isolation. The trip to Mars is about 6 months, and also the trip back is about six months and during those 6 months astronauts will be exposed to unhealthy amounts of radiation and once they get back we want them to go do parades and be national heroes; we do not want them to die of cancer.

Considering that some Apollo astronauts suffered cataracts because of their very limited exposure during their 12 day missions, protecting the Mars crew on a mission that's 50 times longer than that turns out to be a pretty tremendous challenge. There are ways, of course, to block radiation including thick pieces of plastic and even water, but those things are heavy, and heavy is bad, when it comes to spaceflight because that means more fuel, more expense, and less chance that its actually going to happen.

And the sun is a tricky beast. Sometimes it'll be you know pretty manageable background levels of radiation, but occasionally it shoots out these giant bursts of solar energy in the form of solar flares. A large solar flare could kill a crew in a matter of minutes. At the very least, everybody knows that there's going to have to be at least some small area of the crew cabin that will have really thick lead shielding in the event of a solar flare, but again, lead is heavy.

And then there are questions of how a crew would deal with being in a confined environment for a mission that, is in all probability, longer than two years, and also, with the same few people for all for that long. I can't even have a roommate. Can a crew of six men (and women) maintain their sanity, and their physical well being, on a really long isolated mission.

The initial answer to that question appears to be yes. In fact, an international crew in Russia just finished a 520 day mission. During this $15 million mission, the crew of 6 men experienced conditions similar to what it would be like to go to Mars. They even got to Mars, and they were able to explore Mars, which was about the size of a tennis court, and then they got back in, and had to be confined in their thing for another huge amount of time.

I'm making fun of this, but it's actually a really cool and useful experiment, and huge amounts of data were collected and are still being collected. The European Space Agency and the Chinese governments are analyzing those data now which include tons of information on the psychological and physical well-being of the people involved. The six man crew emerged from their mission, pale from the lack of sunlight but otherwise in good spirits after going absolutely nowhere for a really long time.

Our old friends back at the Mars Society have also been running similar experiments for years now. They just started the new Mars desert research station which is in all places Hanksville, Utah. The goal here is not so much how to deal with isolation as it is to figure out how to make the most of a mission in a harsh environment. I love the MRDS, and not just because it's in Hanksville, Utah, also because, you know, when we get to Mars someday we damned well better know how to make the most of it.

Last year alone there were 8 different mission crews from various universities and space academies that rolled through the research station. These crews are testing habitat designs, exploration strategies, figuring out what tools astronauts are going to need on the red planet.

#3 The Money
Given the world wide economic climate coming up with the billions of dollars necessary to send people to Mars turns out to be a bit of a challenge. And that's before we even get up in space. And given that no official mission exists - yeah I'm not counting "we'll get there in the 2030s" as a plan - cost estimates for getting humans to Mars are hilariously all over the spectrum. From 20 million dollars to 400 billion dollars it's futile to say anything other than it's going to be extremely expensive. For now we can look at ways we can potentially bring the cost down like international partnerships, and dealing with private firms like SpaceX. For example Zubrin noted to me that NASA's budgeting about 18 billion dollars for their space launch system, but he thinks it can be done for less than 5.

So just 5 billion dollars. And I... probably got that lying around somewhere.

And #4, the why. One of the reasons why I joined the Mars society as a young man was because I was inspired by that optimism, the idea that people can get together and do something really really huge. You know it's possible to convince everyone in the world that going to Mars is technically and physically and even financially possible, but you can't convince everyone that it's something that we should do.

One of the best explanations for why we should do this is from the Mars Society's founding declaration. I'm going to read it to you now.

"Civilizations like people thrive on challenge and decay without it. The time is passed for human society to use war as a driving stress for technological progress. As the world moves toward unity we must join together not in mutual passivity but in a common enterprise facing outward to embrace a greater and nobler than that which we previously posed to each other."

And now I'm gonna let 17 year old Hank take us out with some lines from that old editorial.

"Isn't it obvious that Mars is calling to our world. It's a little bit too coincidental for me, almost like there is someone or something out there giving us signs to go to Mars and we need to listen. We have the technology, we have the people, we have the need for a manned mission to Mars so why can't we just do it?"

I have to tell you that that last sentence was in the editorial written in all caps. I can't say that I remain proud of my writing skills as a 17 year old but I can say that I  remain proud of the kind of optimism and excitement that I had and I still have for this kind of enterprise. So I guess, now, all we need is a plan.

Thank you for watching this episode of SciShow. I hope that it was as exciting for you as it was for me. We'll be on twitter and Facebook answering your questions and taking your suggestions, and also of course in the YouTube comments below. Good bye.