Later this year, in September if all goes well, Elon Musk is going to release SpaceX’s plan for colonizing Mars. For now security is tight and details are sparse to nonexistent. We know the company plans to land an unmanned Dragon capsule on Mars as early as 2018 as part of this effort. Musk has also said he hopes to follow up with the first humans by 2024 to 2025. Those are ambitious goals, and the timelines are only estimates. They depend on the successful development of the Falcon 9 heavy, for one. But given the recent string of brilliant successes, it’s a good bet that SpaceX will likely deliver.
Making humans a multi-planet species is a worthy goal. In fact it’s the only path to really long-term survival. But there’s another object much closer that we could also colonize—and that’s the moon. Many NewSpace activists agree: It’s not an either/or, it’s both and more. Mars has advantages, like an atmosphere and an abundance of water ice, and it has disadvantages, like distance. So they see the moon and Mars and even free orbiting habs all as equally viable colony sites. Follow below for a few reasons why some futurists think the moon makes sense as a first stop, or at least an important stop, on the way to the rest of the solar system and beyond.
The moon is smaller than Mars and much, much closer. Moreover, it orbits Earth and it’s only three days away by spacecraft. What that means is the moon is a far better logistical proposition for getting to, getting back, and living on than any other major body in our solar system.
A spacecraft can be put in the looping, figure-eight lunar Free Return Trajectory. Once placed in FRT, It will continue in that orbit, with minor station-keeping burns and tweaks, indefinitely. The total round trip is about a week and it allows us to test out an interesting idea: cyclers.
A cycler is a spacecraft on a permanent orbit between two objects. In the case of the moon, it would follow that looping figure eight, passing close to the Earth and the moon at each end making it convenient to detach and brake for lunar touchdown, or detach for reentry on Earth. It’s not a free ride: A spacecraft would still have to match velocities with the cycler, but it does mean we can have a large moving base of sorts without having to use precious fuel to boost it into FRT on every trip. That’s important for a number of reasons, not the least of which is the threat of solar storms.
Meteorites and cosmic rays aren’t much of a threat to interplanetary missions. But a mediocre coronal mass ejection from the sun that would barely be noticed on Earth would cook unprotected astronauts with deadly hi-energy radiation. It takes several meters of water or other material to shield from this onslaught. A large spacecraft similar in size and functions to a space station would have the mass and structure necessary to mitigate that danger. And cyclers are possible for other objects like Mars. Using one in FRT as a sort of luxurious, moving space hotel and ride to the moon would allow us to test the cycler technology in a relatively safe way.
The moon has one-sixth the gravity of Earth. But that doesn’t mean lunar surface-to-orbit spacecraft have to be one-sixth the size of a Saturn V. Because of some basic physics, a tiny rocket motor and small amounts of fuel are all it takes to fly over the moon like Buck Rogers with a jetpack. A rocket engine the size of a large coffee can and several dozen pounds (moon-weight) would probably be enough to boost a human-sized mass into lunar orbit. Getting to and from the moon isn’t just fast compared to Mars, it’s way more economical.
Like Mars, the moon appears to have lava tubes that would make ideal places to build the first habitats. They come in all sizes. Some of them even come equipped with a skylight—a place where the top of the tube has caved in and we can see all the way through to the floor. If pressurized and covered with a clear layer, such a place might make an ideal atrium or farm. Make it big enough and colonists could easily fly around in the low gravity on a pair of muscle-powered wings.
One of the most exciting reasons for visiting the moon, again, and setting up permanent bases this time, is comprehensive exploration. We tend to think of the moon as a boring, dead world, a surface rendered by nature and exo-geology in old fashioned black and white. But we have only explored a tiny fraction of one percent of its surface and we purposely landed in areas that were, for safety reasons, flat, boring-looking places.
The moon’s surface is very old, but long ago it may have had short-lived watery lakes and we know it had oceans of magma and active volcanoes. Once something precipitates out, roils up from below, or crashes in from above, it will stay mostly preserved by vacuum on a now eternally unchanging surface in relatively pristine condition. We have no idea what ancient scientific treasures might be lurking right out in the open or poking out from just under the lunar regolith. Intact pieces of Theia, rocks from exo-solar systems, traces of space-borne bacteria, a black monolith, or... ?
Lastly, the moon could provide a much-needed public stimulus for our government and private space programs. Mars is a great goal, everyone is excited about it and we all wish SpaceX the very best. But few laypeople can locate the dull red spark that marks it in the night sky without help. The moon is an old friend, it is ubiquitous and grand and gorgeous throughout all human history. It fires our imagination. Poems and songs have been written about it for generations, new couples have gazed into one anothers’ eyes under its silvery light and fallen in love, and at times and places it has been worshiped as a god.
“Cold-hearted orb that rules the night, removes the colors from our sight, red is gray and yellow white, yet we decide which is right” — Moody Blues, Nights in White Satin.
The moon has ruled the night for more than four billion years. It seems to invite those with the means to come visit it, and since we now have those means, perhaps we should take that friendly invitation more seriously.