



The Why, When, and How of a Manned Mission to Mars

U.S. News & World Report ranks the undergraduate program in Georgia’s Tech’s Daniel Guggenheim School of Aerospace Engineering No. 2 in the nation. Two of its leaders, Professors Bobby Braun and Dave Spencer, have a long history with Mars.

Braun was a member of the Mars Pathfinder entry, descent, and landing team in 1997 and has been a part of every Mars landed mission since. He’s now the chair of the standing review board for the Mars 2020 Project, NASA’s next large rover mission.

Spencer was also on the Pathfinder team as mission designer while working at the Jet Propulsion Lab in California. He went on to serve as the Mars Odyssey mission manager (2001) and was the deputy project manager for the Phoenix Mars lander (2008). He joined Georgia Tech after leading Phoenix surface operations.

Braun and Spencer sat down to discuss and debate when humans will get to Mars, the cost of this unprecedented mission, and the technical challenges of making the historic journey.

Why should humans go to Mars?

Spencer: Exploration is in our DNA. It’s what we as a people, and the United States in particular, are built upon. Mars is the next logical step and the direction our species is headed toward.

Braun: NASA was built on big goals and dreams. Achieving large goals is precisely what the nation expects from its space program. A great way to build U.S. scientific and technological competence is by aiming large.

Why can’t we go there now?

Braun: We could choose to start sending humans to Mars in the next decade if we put our minds to it. The pace of our journey is driven by the pace of our investment in the technologies and capabilities needed for exploration.

Spencer: There’s a fundamental difference between the way the Apollo missions were undertaken versus the current way the Mars exploration program is conceived. Apollo had a very clear set of goals to launch humans into space within a decade. Now, the mindset is that we’re operating under a fixed budget, we must live within it, and only build as we can. That’s a very slow process.

Braun: In the Apollo days, the NASA budget was 10 times what it is today. It was roughly 4 percent of the gross domestic product. Now it’s about .4 percent. Imagine if revenues for a university or a computer company were one-tenth what they were 50 years ago.

Why is it so different?

Braun: Apollo wasn’t really about sending people to the moon within a decade. It was about proving the technological superiority of the United States in a race with the Soviet Union. That’s why funding poured into NASA. It’s a different world now. People who are waiting for the next Kennedy moment are going to wait a long time. I think we’re going to have to figure this out within the general federal funding guidelines that have been in place since the Nixon administration: NASA has to take its rightful place in the federal budget among the other priorities the United States invests in.



Spencer: So that means an international collaboration is essential for something as complex and expensive as going to Mars.

Braun: Yes. And more significant partnerships with the U.S. commercial space sector.

What are some of the biggest technological challenges?

Spencer: A round trip is a minimum of two years: at least six months to get there, one year on Mars, and about six months to get back. The radiation exposure an astronaut would get during that time period is a large fraction of what’s considered to be a safe level of radiation dosage for a lifetime. Radiation shielding is needed, but that adds mass. And mass is one of the key costs of going into space.

Braun: And then there’s landing very large payloads. The Curiosity rover is the largest thing we’ve ever put on Mars, and it’s the size of a small car. For humans, we’re talking about landing a series of two-story houses to establish a base camp. We also need to improve the efficiency of our propulsion systems for the flight to Mars and learn to make use of the surface resources available once there.

Mosaic of the Valles Marineris hemisphere of Mars projected into point perspective, a view similar to what one would see from a spacecraft. Image credit: NASA/JPL-Caltech

Would people come back from the first mission?

Braun: I hope so. There are groups that want to do pure settlement: a one-way trip. But I don’t think the U.S. and the world would make the investment if it were a one-way trip. I think the reason you send people to Mars is to bring them back so they can be heroes and inspire billions of others — like the Apollo astronauts. I would want to meet them. Wouldn’t you?

Spencer: It’s in our culture that the initial explorers go and come back. Think about Lewis and Clark, who returned to civilization after exploring the western part of the continent. Eventually, and not much later, people went out and settled the American West in large numbers.

Braun: Personally, I think there will be a handful of round-trip missions before we start settling.

When will people land on Mars?

Spencer: No earlier than 2040 and no later than 2100.

Braun: Eight years after we decide to do it. In other words, eight years after we have made considerable investments in proving the capabilities needed. We need a few capabilities for this mission: a big rocket, radiation shielding.

Spencer: An ascent vehicle.

Braun: Right. There are about six capabilities needed for a human Mars mission. Right now we’re probably investing in three of them, and at a very low level. I’ll know we are serious about sending people to Mars when I see this country and others invest in the needed capabilities in a significant way. Once we do, we’ll land eight years later.

Spencer: You’re more optimistic than I am.

How much money will it take?

Braun: A lot for the space program, but not very much for the world.

Spencer: At least $100 billion spread over 10 years. That’s not that much. You can spend a billion dollars easily on a relatively common infrastructure project. What does a football stadium cost? $1 billion?

Braun: Roughly $10-$15 billion a year for a decade. Right now NASA’s yearly budget is about $18 billion, and we spend about half of that on human spaceflight. If the rest of the world (Russia, China, Europe) matched the U.S. investment, Mars would be within our grasp.

Final question: What does Martian exploration look like 100-150 years from now?

Spencer: It will be like Antarctica is today: People will be ferried to the surface to do research for a certain time period and then return. There will be crops on Mars. But it will be a small footprint – it’s tough to live up there. But we will.

Braun: One hundred years from now, our space program will be even more significant and more ubiquitous to life on Earth. We’ll have journeyed to the ocean worlds in the outer solar system, where many believe there may be life waiting to be discovered. We’ll have learned about other earths around distant stars. We’ll have imaged them and seen blue oceans and white clouds. In 100-150 years, we will have settled Mars at some level, as well as answered other fundamental societal questions such as: Are we alone and where did we come from?



How do you find life on Mars?

Amanda Stockton is an assistant professor in the School of Chemistry and Biochemistry. Her research focuses on the origin of biomolecules and the emergence of life on Mars and throughout the galaxy. She doesn’t just cook up chemical reactions in her lab — she builds instruments she hopes will fly someday to Mars and search for the basic building blocks of life, whatever it may happen to look like 140 million miles from home.

How do you find life on Mars when it’s completely different from life in a totally different chemical and thermodynamic environment? There’s no reason to think that it’s anything like what we have here. We can’t assume it’s chosen the same building blocks as what makes up our proteins or DNA.

Here’s another way of thinking about it: There are 20 amino acids on Earth. They build the enzymes that create the fingerprint of terrestrial life. There are more than 100 amino acids found in meteorites. The fingerprint, if you even want to call it that, is completely different. You can’t assume Martian life would have the exact same 20-amino-acid fingerprint as Earth.

Amanda Stockton holds a programmable microfluidic device that enables automated sample processing and analysis of amino acids. Photo: Fitrah Hamid



But here’s the bigger issue — we have to quit sending the same instruments up there. We’ve never sent or used an instrument on Mars that can directly detect amino acids. We’re doing the chemistry wrong. Instead of heating samples and watching for organics to evaporate into a gas analyzer, we need a wet-extraction method that sends samples to a liquid analyzer. We need a fancy Martian espresso maker — something that can dig into the soil, put it into a liquid and a tool that can analyze the Martian espresso directly. That’s when we’ll truly know what’s in the dirt.

I think there’s life on Mars. We can get really far with analytical instruments, but to absolutely confirm it, you have to eventually send people. Robots and rovers can’t think for themselves and recognize those patterns indicative of life, like faces and fingerprints. Humans can. But that brings up a different issue: People are living, breathing bags of bacteria capable of contaminating the planet. So when humans get there, we’ll start searching and could very likely find only what we brought with us.

Humans on Mars prediction:

We have all the science and engineering in place to go right now. We just need to do it. All we’re lacking is the funding and the political will. I really don’t want us to go and contaminate the planet until an unmanned mission is able to return a definitive answer about life up there. Without that, we’ll never know what’s native and what came along with us. So I’m thinking somewhere between 2040 and 2050.