Just in case you missed the story yesterday, hundred-millionaire and first commercial spaceflyer Dennis Tito has made a preliminary announcement of plans to launch a 501-day roundtrip Mars mission in January 2018 - less than five years from now - and will provide details next week on the 27th. This led to speculation (on my part as well) about exactly what kind of Mars mission it would be, with some thinking it might be unmanned, or if manned, wondering whether it would involve a landing. There are now overwhelming indications that (a)it is a manned mission, and (b)there will not be a landing, but rather the mission would be a flyby of Mars on a free-return trajectory.
This information comes from a brief post on NewSpace Journal that notes Tito is due to give a talk at the IEEE Aerospace conference March 3rd with the title "Feasibility Analysis for a Manned Mars Free Return Mission in 2018":
This publication obtained a copy of the paper Tito et al. plan to present at the conference, discussing a crewed free-return Mars mission that would fly by Mars, but not go into orbit around the planet or land on it. This 501-day mission would launch in January 2018, using a modified SpaceX Dragon spacecraft launched on a Falcon Heavy rocket. According to the paper, existing environmental control and life support system (ECLSS) technologies would allow such a spacecraft to support two people for the mission, although in Spartan condition. “Crew comfort is limited to survival needs only. For example, sponge baths are acceptable, with no need for showers,” the paper states.
For help understanding what this kind of trajectory would look like, here is an example of one such trajectory based on a typical orbital diagram:
A number of milestones will need to occur on the part of SpaceX before such a mission can occur, but fortunately most of them are already underway:
1. Human-rate the Dragon spacecraft.
SpaceX is presently pursuing this as part of its bid to win NASA crew transport contracts to deliver astronauts to the International Space Station, and plans to have it launching crew to Low Earth Orbit (LEO) as early as December 2015. Dragon was designed and built from the very beginning with crew transportation in mind, so this is a natural and deliberate evolution. A key test in this program - a "pad abort" where Dragon will launch itself off the Falcon 9 on the launch pad to simulate an emergency abort - is planned for as early as December of this year. The next key milestone, an "in-flight abort" - where the Falcon 9/Dragon will be launched and Dragon will then blast away from the rocket on ascent to simulate an in-flight emergency - is planned for as early as April of next year.
2. Develop Falcon Heavy.
The Falcon Heavy rocket is a heavy-lift variant of the Falcon 9 that would be needed for Mars mission hardware, and its development is already underway with the maiden flight scheduled for this year. The primary developmental milestones may already have been met, or are close to being met - basically, just extend the current Falcon 9 fuel tank, rearrange the engine configuration into a circle of 8 engines with 1 in the middle (the current arrangement is a 3-by-3 square), and then strap two additional first stages on the sides.
I don't have enough information to figure out how much mass would need to be launched for this mission, but the highest list price for a Falcon Heavy launch is $128 million, and it's entirely possible that Elon Musk would be willing to subsidize such a mission since human colonization of Mars is the raison d'etre of SpaceX. If Tito's plan succeeded, it would inject a truly massive level of interest, inspiration, credibility, and possibly investment toward that objective.
3. Modify the Dragon for long-term habitation Beyond Earth Orbit (BEO).
This is the tallest order on the list, because the needs of BEO travel are significantly greater than those of LEO - particularly as it concerns radiation shielding, electronics hardening, and designing for massive redundancy far beyond what is acceptable for Earth orbit. On a 501-day trip to and from Mars, there is simply no way to get back home in time to survive if a catastrophic failure on the level of Apollo 13 were to occur, so the systems have to be as unkillable as the state of engineering and money permits. As a result, a manned BEO spacecraft designed for long-term missions has to be an order of magnitude more complex and robust than a short-term LEO transport, may have greater power requirements necessitating larger solar panels, and would also be considerably heavier.
SpaceX has long-term plans to evolve Dragon into a BEO craft, but as far as I know the first steps toward that are still a ways away, and would certainly have to come after experience had been built up using it for crewed LEO missions. Perhaps this mission and the resources devoted to it could cause SpaceX to place a higher priority on BEO Dragon development. To get a sense of the internal volume of Dragon, here is a panoramic zoom app of an empty cargo Dragon - you can drag the image a full 360 degrees in any direction, and also zoom in and out:
http://www.spacex.com/...
Also, here are mock-ups of the currently envisioned interior of the LEO taxi version of Dragon, seating seven astronauts:
Since the plan calls for two astronauts, they would have considerably greater space to work with than the 7-member crews who would be using Dragon as a space station taxi. However, even with that advantage, 501-days inside a Dragon - most of the time with nothing to see out the window - would seem like a mental health nightmare. We will have to wait for the press conference on the 27th to get further details, but this preliminary information makes no mention of Bigelow modules or other volumetric extensions to create more space for the astronauts, and the emphasis on "Spartan" conditions suggests that the astronauts would be confined to a single BEO Dragon for the entire mission. Bigelow habitat modules would be a Good Idea, but if necessary to afford the mission, it seems the plan could still succeed only using them for cargo storage while limiting the living space to Dragon.
Human beings have survived under worse conditions for longer - people chained in pitch-black dungeons for years on end come to mind - but I would not envy the astronauts on such a mission. Personally, I would be too crazy and ill from stress by the time I got to Mars to appreciate it, but then astronauts are made of sterner stuff, and I believe such a mission is achievable. The current record for time in space is 437.7 days, but that was on a space station with gorgeous views of a brilliant blue planet and night-lit cities constantly passing below - also with the promise of an emergency return within hours if something went awry. The psychological stresses of this Mars mission would be on a whole other level, especially if, as stated, only the barest requirements of survival are cared for rather than comforts. In terms of time and danger, it harks back to the epic voyages in the Age of Exploration, and would break new ground in the reach of the human species. Yeah, this is exciting.
What remains to be seen is whether Tito already has the money for this. We know he's worth 9 figures, but even if the cost of the mission is on that level, we don't know if he personally has enough or, if not, whether he has already lined up additional partners. If the funding is ready, the mission is very credible, and I see no reason it would not happen. However, if the funding is not already in the bag, despite the plausibility of the mission plan, it simply will not happen because they would need to begin work immediately in order to make the 2018 deadline - and it is a deadline, because it's based on a rare launch window opportunity that won't recur until 2031. That is the key piece of information to look for in the press conference next week, and that will determine if this happens: Is the money already taken care of? If he says "We're lining up investors," or "We're seeking investment," then it just won't happen.
In addition, there are indications that Tito may not himself be on the mission in recognition of his advanced age, but is rather playing the role of financier and organizer. Younger crew would greatly improve the odds of both crew surviving: No matter how spry a person is, you don't subject a 78-year-old to unrelenting superhuman rigors for a year and a half straight. Pending information on the financial situation, I will state plainly that this can happen. Two human beings may be swinging by Mars in April of 2019. Imagine video of this passing by out a window: