Lunar habitat mockup. (Courtesy of Lockheed Martin)

When are we going to Mars? The aerospace giant Lockheed Martin’s answer is 2028 — but that date comes with an asterisk.

The company last week unveiled its vision of a “Mars Base Camp.” This is a 256-foot segmented spacecraft that would carry astronauts to Mars just 12 years from now, under the Lockheed timeline. The asterisk is that the astronauts wouldn’t land, but would stay in orbit around the Red Planet, and eventually rocket back to Earth.

Lockheed’s vision of an orbital mission is somewhat pragmatic as humans-to-Mars concepts go. A Mars landing is exceedingly difficult, because the atmosphere is too thin to be of much help with aerobraking or parachutes, but it is thick enough to cause turbulence or burn up your spacecraft if you’re not careful. The aerospace wizards have managed to land something as massive as a small car on Mars (the Curiosity rover), but to put humans on the surface they'd need to land something the size of a two-story house. So Lockheed’s vision starts with an orbital mission, with a landing sometime down the road — maybe 2033, Lockheed's chief technologist for exploration systems Tony Antonelli told The Post.

“Twenty thirty-three is definitely plausible,” Antonelli said. “The first thing is to get folks excited about going. It’s got to be tangible. We think the technology exists today to pull off the orbital mission.”

The Mars Base Camp. (Courtesy of Lockheed Martin)

He said his company is working actively on what it would take to land humans on the surface of Mars.

“We’re working on that today. The technologies exist, and that’s why we want to push for this capability for an orbiting Mars laboratory with scientists in Mars orbit.”

A couple of things jump out from this proposal. The first is the date. It outpaces, to a modest degree, what NASA has been saying. The year 2028 sounds a little ambitious given the number of elements that have to be pre-staged (including the rovers on the surface of Mars that the orbiting astronauts would manipulate remotely), and the hardware that still needs to be built. To send humans to Mars you need a habitation module, something much bigger than a capsule, because it's a trip that would take anywhere from 6 to 11 months one-way, depending on the year and the ratio of propellant to payload (go slower and you can send a bigger crew and more material, including spare parts for when things break). NASA has yet to issue any contracts for the construction of a habitation module. Keep in mind that Lockheed got the contract to build the Orion spacecraft in 2006 — and the capsule still isn't finished.

Perhaps Lockheed took note of the big headlines SpaceX received when it announced last month that it would send an uncrewed capsule to the surface of Mars as soon as 2018.

People like dates. A date like 2018 or 2028 takes a notional idea — a concept that’s not much more than a PowerPoint slide at this point — and makes it more arresting. But Lockheed says this would be a NASA-run operation, likely with international partners. Lockheed doesn’t make the call on the date. The company is not going to go unilaterally. NASA and its partners would decide. And NASA has other plans for the 2020s.

NASA has said that’s the decade in which it will send humans to the “proving ground.” This is a fairly new way to brand "cislunar space." The exact parameters of the Proving Ground aren’t entirely clear, but would include missions in orbit around the Earth's moon. NASA and its partners might also send a crew a million miles from Earth (roughly four times farther than the moon) in a “shakedown cruise” to test long-duration spaceflight hardware and the physical effects of venturing beyond the planet’s protective magnetic field (which blocks much of the harmful radiation that saturates deep space).

So why did Lockheed say 2028? Antonelli said the company believes that existing technology puts the United States on pace for a mission about that time, with the “shakedown cruise” happening as soon as 2026. And the 2028 date leaves room to follow up the orbital Mars mission with a more ambitious effort to land humans on the surface in 2033 — the favored date of many people in the space policy world, including the powerful chairman of the Science, Space and Technology Committee, Rep. Lamar Smith (R.-Tex.). Thus Lockheed’s date slots nicely amid some favored bureaucratic and political timelines.

Another interesting detail: The Lockheed plan uses two Orion capsules. The company has the contract for these spacecraft, which have been 10 years in the making. Skeptics have noted that it's not entirely clear where Orion is supposed to go. The capsules were originally designed for lunar missions (a separate lunar lander would have taken astronauts to the surface). President Obama canceled George W. Bush's Constellation program, which included moon landings. Congress stepped in and saved elements of Constellation, including Orion and the big rocket now known as the Space Launch System. Ask someone at NASA or Lockheed what all this hardware is for, and you'll hear that it's part of the "Journey to Mars." So now we have the Mars Base Camp — launched with SLS rockets and using a pair of Orions. Message: These aren't Rockets and Capsules To Nowhere after all!

NASA has not yet decided how and when it will go to Mars and is keeping its options open. That can drive a lot of people crazy, because it can seem halting and indecisive, but it's politically savvy and makes some technological sense. On the politics side, you don't want to craft a mission that's too closely branded as a presidential directive. Because then the people in power who don't like that president will try to shoot it down. And technology evolves. NASA doesn't want to get locked into an architecture in 2016 if the mission to Mars is going to be in the 2030s. It can't put off these decisions forever — at some point you have to call your shot — but the agency probably has a few years to play with.

Meanwhile, Elon Musk and his SpaceX folks have consistently said they can send astronauts to the surface of Mars in the 2020s — but that's a whole 'nother story.

Further reading:

Andy Weir, author of 'The Martian,' aims his pen at the moon

Meet Lockheed’s Outpost, a habitat for the ‘proving ground’ of space

NASA's Mission Improbable

Which way to space?

Cool graphic: Deconstructing the International Space Station