# Is there any reason to send a manned mission to Mars? **URL:** \ **Category:** Factual Questions\ **Created:** [May 30, 2015, 12:50pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194 "2015-05-30T12:50:44Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Mr.Kobayashi](https://avatars.discourse-cdn.com/v4/letter/m/4af34b/32.png) [@Mr.Kobayashi](https://boards.straightdope.com/u/Mr.Kobayashi)\ **Post date:** [May 30, 2015, 12:50pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/1 "2015-05-30T12:50:44Z")
…rather than probes? From a strictly practical and scientific standpoint; let’s take as read that the feat and accomplishment of sending men over a machine is the biggest point in its favour. But is there anything a team of humans could do out there that a machine could not? Question inspired by an article I think I read in _The Times_ (can’t find it now), where it was argued that sending men to Mars was at best pointless and at worst needlessly dangerous. ---
**Author:** ![AK84](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@AK84](https://boards.straightdope.com/u/AK84)\ **Post date:** [May 30, 2015, 1:37pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/2 "2015-05-30T13:37:26Z")
Men can do much more than a machine in absolute terms. Just compare the science that was obtained from the Manned lunar missions with what was got from the unmanned [Soviet Lunokhod programme](http://en.wikipedia.org/wiki/Lunokhod_programme) which happened at the same time. What makes probes more attractive now is the fact that the cost and complexity of sending men there witth current propulsion technology. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [May 30, 2015, 2:06pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/3 "2015-05-30T14:06:43Z")
The purpose of the human (crewed) space flight program is not science. The purpose is to learn how to send humans to space. Sending humans to Mars is not the means, it is the goal. If all we were interested in is science, then robots and unmanned sample-return missions would be much more cost-effective. Human scientists would still need surface transport, analysis equipment, remote sensing instruments (to know where to go), and a way to return to Earth with the samples they collected. For much less cost, we could send those same equipment with computers and operate them from earth. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [May 30, 2015, 2:08pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/4 "2015-05-30T14:08:51Z")
**AK84** : I’m not sure that’s a very valid comparison. Humans in 2015 are only slightly, if at all, more capable than humans in 1969. Robots have become several orders of magnitude more capable over the same interval. Society, or at least US society, has become much more danger-averse over the same time. So the \*(cost+risk) / benefit \*tradeoffs are much more in favor of machines now than they were then. ---
**Author:** ![AK84](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@AK84](https://boards.straightdope.com/u/AK84)\ **Post date:** [May 30, 2015, 2:28pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/5 "2015-05-30T14:28:24Z")
> [@LSLGuy](#): > > **AK84** : I’m not sure that’s a very valid comparison. > > Humans in 2015 are only slightly, if at all, more capable than humans in 1969. Robots have become several orders of magnitude more capable over the same interval. > > Society, or at least US society, has become much more danger-averse over the same time. > > So the \*(cost+risk) / benefit \*tradeoffs are much more in favor of machines now than they were then. Well good thing its not just the US who is interested in it then!😉 Compare then the Jade Moon rover the Chinese sent only last year. It still did only a fraction of what even one Apollo Astronaut could do. All a machine can do is what its programmed to do. Humans are flexible and creative. Could any rover at present or feasibly thought of do what any Apollo astronaut did? Scott and Irwin discovering the Genesis Rock? Or Cernan and Schmitt finding orange soil on the moon? No. If they choice between a man and a machine exists then the better choice is to send a man. Right now however, there is no choice. We send robots because we have no alternative. ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [May 30, 2015, 2:39pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/6 "2015-05-30T14:39:45Z")
> [@LSLGuy](#): > > Humans in 2015 are only slightly, if at all, more capable than humans in 1969. Robots have become several orders of magnitude more capable over the same interval. Yes, but a human can look at a jumble of rocks, move to different positions to look at them, walk around them and up a slope to get to an interesting formation, and then do any of a hundred different things once she’s there. In two or three precious minutes. Robots need two days to move carefully around a slope that’s judged greater than zero hazard, need hours to position themselves so their manipulators can reach the target, then do some very limited number of things with the access. We’re a long, long way from closing that gap. > [@](#): > > Society, or at least US society, has become much more danger-averse over the same time. We aren’t talking about society, we’re talking about NASA, which was extremely risk-averse at its formation, became an order of magnitude more so after Apollo 1, and turned into a fretful old lady after Challenger. Quite simply, we’d have a sustainable colony on both Luna and Mars if NASA accepted the same risks we do for driving on highways, building large structures and allowing junk food to be literally rammed down our throats. All that “right stuff” booshwah came from a legion of test pilots who knew they had the mortality rate of a D-Day platoon and went up anyway. Maybe that was craziness, but so is the 0.001% chance of failure fretfulness of NASA. ---
**Author:** ![Gorsnak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gorsnak/32/7587_2.png) [@Gorsnak](https://boards.straightdope.com/u/Gorsnak)\ **Post date:** [May 30, 2015, 2:41pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/7 "2015-05-30T14:41:59Z")
> [@AK84](#): > > Well good thing its not just the US who is interested in it then!😉 > > Compare then the Jade Moon rover the Chinese sent only last year. It still did only a fraction of what even one Apollo Astronaut could do. All a machine can do is what its programmed to do. Humans are flexible and creative. Could any rover at present or feasibly thought of do what any Apollo astronaut did? Scott and Irwin discovering the Genesis Rock? Or Cernan and Schmitt finding orange soil on the moon? No. > > If they choice between a man and a machine exists then the better choice is to send a man. Right now however, there is no choice. We send robots because we have no alternative. Programming is flexible. New firmware can be uploaded, new instructions can be sent. Granted, humans are capable of much more advanced autonomous decision-making, and are more likely to find and exploit serendipitous opportunities than robots are, at least at the current time. Machines can also do many things that humans cannot, not least of which is survive on the surface of Mars without shelter or supplies for years. Given the time between Earth-Mars Hohmann transfer windows and the delta-V requirements for returning outside of those windows, that advantage overwhelms all other considerations. ---
**Author:** ![Amateur\_Barbarian](https://avatars.discourse-cdn.com/v4/letter/a/59ef9b/32.png) [@Amateur\_Barbarian](https://boards.straightdope.com/u/Amateur_Barbarian)\ **Post date:** [May 30, 2015, 2:43pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/8 "2015-05-30T14:43:05Z")
> [@AK84](#): > > If they choice between a man and a machine exists then the better choice is to send a man. Right now however, there is no choice. We send robots because we have no alternative. Yes, we do. We could send a mission to Mars right now… if we accepted that 100% mortality was a risk, 50% mortality was probable and 10-25% mortality was almost certain. But no; any risk to the crew greater than sitting in NASA’s anechoic chamber is Not Acceptable. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [May 30, 2015, 2:52pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/9 "2015-05-30T14:52:41Z")
> [@AK84](#): > > Compare then the Jade Moon rover the Chinese sent only last year. It still did only a fraction of what even one Apollo Astronaut could do. You’re comparing a [$230 million](http://www.dailytech.com/Chinas+Lunar+Rover+Enters+Orbit+Prepares+for+Historic+Sat+Landing/article33930.htm) mission to a $100 **b** illion program. ---
**Author:** ![NineToTheSky](https://avatars.discourse-cdn.com/v4/letter/n/b5a626/32.png) [@NineToTheSky](https://boards.straightdope.com/u/NineToTheSky)\ **Post date:** [May 30, 2015, 3:47pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/10 "2015-05-30T15:47:14Z")
Coincidentally, today’s Guardian has [an article on a planned mission to Mars](http://www.theguardian.com/science/2015/may/30/can-mars-one-colonise-red-planet) - but it will be one way only (much cheaper). They already have plenty of people signed up for it. ---
**Author:** ![PatrickLondon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/patricklondon/32/4422_2.png) [@PatrickLondon](https://boards.straightdope.com/u/PatrickLondon)\ **Post date:** [May 30, 2015, 3:50pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/11 "2015-05-30T15:50:03Z")
Long piece about this in today’s Guardian. I’m sceptical about this particular initiative, and while the article suggests the man is more sincere in his intentions than I suspected, it’s still not very convincing as to the scheme’s plausibility): [http://www.theguardian.com/science/2015/may/30/can-mars-one-colonise-red-planet](http://www.theguardian.com/science/2015/may/30/can-mars-one-colonise-red-planet) ---
**Author:** ![sbunny8](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@sbunny8](https://boards.straightdope.com/u/sbunny8)\ **Post date:** [May 30, 2015, 3:58pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/12 "2015-05-30T15:58:17Z")
> [@scr4](#): > > The purpose of the human (crewed) space flight program is not science. The purpose is to learn how to send humans to space. Sending humans to Mars is not the means, it is the goal. This. If your goal is to learn everything there is to know about the planet Mars, then send ten thousand robots. If your goal is to learn as much as possible about humans and what keeps them alive and how to build a sustainable ecosystem, send a hundred humans to Mars. If your goal is to spread out the human race as far as possible so that the next planet-killer asteroid impact doesn’t mean the end of Homo Sapiens, send a million humans to Mars. ---
**Author:** ![guizot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guizot/32/3636_2.png) [@guizot](https://boards.straightdope.com/u/guizot)\ **Post date:** [May 30, 2015, 4:03pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/13 "2015-05-30T16:03:23Z")
> [@NineToTheSky](#): > > Coincidentally, today’s Guardian has [an article on a planned mission to Mars](http://www.theguardian.com/science/2015/may/30/can-mars-one-colonise-red-planet) - but it will be one way only (much cheaper). They already have plenty of people signed up for it. I wonder how many of those people, after truly proper vetting, will turn out to be not up to the task–people who, in the end, are just grasping at some idea from their science fiction reading fantasies. ---
**Author:** ![Morgenstern](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@Morgenstern](https://boards.straightdope.com/u/Morgenstern)\ **Post date:** [May 30, 2015, 4:10pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/14 "2015-05-30T16:10:00Z")
Let the Chinese waste trillions getting to Mars. Send a robot and be done with it. ---
**Author:** ![NineToTheSky](https://avatars.discourse-cdn.com/v4/letter/n/b5a626/32.png) [@NineToTheSky](https://boards.straightdope.com/u/NineToTheSky)\ **Post date:** [May 30, 2015, 4:11pm UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/15 "2015-05-30T16:11:05Z")
Although the Guardian article mentions it’s one way only mainly for financial reasons, from what I gather it’s likely to be one way because after a considerable time in low or no gravity, the human body will not be able to re-adapt to earth’s gravity. ---
**Author:** ![JohnGalt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johngalt/32/184_2.png) [@JohnGalt](https://boards.straightdope.com/u/JohnGalt)\ **Post date:** [May 31, 2015, 12:16am UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/16 "2015-05-31T00:16:11Z")
That was one of Carl Sagan’s beefs with NASA - robotic missions could get lots more done than manned missions for the same money. I’m thinking this was in _Broca’s Brain_ (1979). I knew he was missing the “human experience” aspect of it, but this was back when the Voyager missions were happening and the entire future of moon and Mars missions were up in the air (ha!). ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [May 31, 2015, 12:51am UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/17 "2015-05-31T00:51:03Z")
Absolutely nothing is known about the long-term effects of low (but nonzero) gravity. Humans have been subjected to 1 g for over a century at a time, and have been subjected to 0 g for over a year, but the longest any human has ever spent at any gravity in between those is less than a week. But even if prolonged exposure to low or zero gravity produces such irreversible changes, the solution is simple: Don’t expose the astronauts to low or zero gravity for so long. There’s no reason that a mission to Mars should need to be zero-g. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [May 31, 2015, 1:13am UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/18 "2015-05-31T01:13:39Z")
A compelling reason for science? No. Mars is a bleak environment, hostile to human life across the board. It would take an incredible investment, effort and infrastructure to support human life in that scenario. Mars is interesting from the aspect of scientific discovery, but in practical terms it offers nothing immediately useful to humans in the near or even far term. Much better to poke at it with robots. If cheaper spaceflight and habitats become available that will work on Mars that determination can be re-evaluated. ---
**Author:** ![zombywoof](https://avatars.discourse-cdn.com/v4/letter/z/9e8a1a/32.png) [@zombywoof](https://boards.straightdope.com/u/zombywoof)\ **Post date:** [May 31, 2015, 1:22am UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/19 "2015-05-31T01:22:15Z")
An [article](http://www.newyorker.com/magazine/2015/06/01/project-exodus-critic-at-large-kolbert) some might find interesting, from the most recent edition of The New Yorker. ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [May 31, 2015, 2:18am UTC](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194/20 "2015-05-31T02:18:53Z")
> [@Amateur\_Barbarian](#): > > a human can look at a jumble of rocks, move to different positions to look at them, walk around them and up a slope to get to an interesting formation, and then do any of a hundred different things once she’s there. In two or three precious minutes. Minutes are indeed precious to a human on Mars - the difficulty, cost and hazard of getting and staying there is simply staggering. Not so with a robotic probe, as our experience on Mars has amply demonstrated - so slow movement is not much of a drawback. I’d guess that in round numbers a capable robotic probe can be sent for 1/400th the cost of a human, and can be expected to explore (with no support beyond what it brings along, i.e. solar panels), for 100 times as long. [Next page](https://boards.straightdope.com/t/is-there-any-reason-to-send-a-manned-mission-to-mars/721194.md?page=2)