Mars or bust!
- Thread starter carmelo
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if you ask me, that's a five year kamikaze project.
alone the Hardware:
Dragon and Biglow Habitat module are not tested for long time space mission for 500 days.
what about failure free Life-support system and supply for 500 day mission ?
and the aerocapute mode is not tested yet
Falcon Heavy has not yet launch and if can bring 50 tons in orbit is doubtful, now its unofficial to be 39 tons.
alone to be on save time they need to launch an unmanned Test mission to test the fly hardware under real condition...
that left them only 3 year on R&D on project hardware.
alone the Hardware:
Dragon and Biglow Habitat module are not tested for long time space mission for 500 days.
what about failure free Life-support system and supply for 500 day mission ?
and the aerocapute mode is not tested yet
Falcon Heavy has not yet launch and if can bring 50 tons in orbit is doubtful, now its unofficial to be 39 tons.
alone to be on save time they need to launch an unmanned Test mission to test the fly hardware under real condition...
that left them only 3 year on R&D on project hardware.
The Economist's take on it
That is not to say that Mr Tito’s plan is timid. On the contrary: it is eye-wateringly (or, as one colleague puts it, “bowel-looseningly”) bold. Although endless studies have been done on how it might be possible to ferry humans to Mars, no one has ever attempted it. Mr Tito’s launch date is fixed, for it is designed to take advantage of a rare period of orbital proximity between Mars and Earth. If he misses his deadline, another opportunity will not present itself until 2031. That gives the team just under five years to design the mission, specify a spacecraft, find a rocket to launch it on, select a crew and carry out all the necessary checks and double-checks. And, without the financial muscle of a nation-state behind him, all this must be done on a budget.
Mr Tito’s press conference was, understandably, rather short on technical details. But a few did emerge. There will be only two crew members, for instance—a husband and wife, both middle aged. The hope is that choosing a married couple will keep any interpersonal friction to a minimum during a year and a half spent inside a craft no bigger than a motor home (though some spouses would surely challenge this logic). Picking astronauts in their 40s or 50s, meanwhile, will lessen the impact of the large radiation dose that both can expect to absorb (radiation, of course, being potentially damaging to fertility). To keep costs down, and to avoid relying on new (and therefore untested) technology, the mission will, wherever possible, recycle technology that is already in use on the International Space Station.
Still, there is a host of unresolved questions. Radiation is one. Data from existing probes suggest that, although the crew will accumulate a significant dose, the radiation levels in interplanetary space should not be fatal. But a mission with a flight time of a year and a half risks encountering the much fiercer radiation generated by coronal mass ejections, unpredictable events in which the sun blasts huge quantities of plasma into space. Exposure to such a radiation storm could be lethal. There is, as yet, no generally agreed-upon way of protecting a crew from its effects. The sun ought to be in a relatively quiet part of its 11-to-14 year cycle by the time the mission launches, but that merely reduces the risk—it does not eliminate it.
The return leg of the trip poses problems of its own. To keep fuel use (and therefore mass) to a minimum, the spacecraft will be on a so-called “free return” trajectory, in which the mission planners rely entirely on gravity to guide their craft through space. That means that, by the time the crew return to Earth in 2020, they will hit the atmosphere at speeds in the region of 51,000kph, smashing the re-entry speed record held by the Apollo crews. It is not clear whether any existing heat-shield technology could protect them. Mr Tito said he was working with NASA to investigate the problem.
That is not to say that Mr Tito’s plan is timid. On the contrary: it is eye-wateringly (or, as one colleague puts it, “bowel-looseningly”) bold. Although endless studies have been done on how it might be possible to ferry humans to Mars, no one has ever attempted it. Mr Tito’s launch date is fixed, for it is designed to take advantage of a rare period of orbital proximity between Mars and Earth. If he misses his deadline, another opportunity will not present itself until 2031. That gives the team just under five years to design the mission, specify a spacecraft, find a rocket to launch it on, select a crew and carry out all the necessary checks and double-checks. And, without the financial muscle of a nation-state behind him, all this must be done on a budget.
Mr Tito’s press conference was, understandably, rather short on technical details. But a few did emerge. There will be only two crew members, for instance—a husband and wife, both middle aged. The hope is that choosing a married couple will keep any interpersonal friction to a minimum during a year and a half spent inside a craft no bigger than a motor home (though some spouses would surely challenge this logic). Picking astronauts in their 40s or 50s, meanwhile, will lessen the impact of the large radiation dose that both can expect to absorb (radiation, of course, being potentially damaging to fertility). To keep costs down, and to avoid relying on new (and therefore untested) technology, the mission will, wherever possible, recycle technology that is already in use on the International Space Station.
Still, there is a host of unresolved questions. Radiation is one. Data from existing probes suggest that, although the crew will accumulate a significant dose, the radiation levels in interplanetary space should not be fatal. But a mission with a flight time of a year and a half risks encountering the much fiercer radiation generated by coronal mass ejections, unpredictable events in which the sun blasts huge quantities of plasma into space. Exposure to such a radiation storm could be lethal. There is, as yet, no generally agreed-upon way of protecting a crew from its effects. The sun ought to be in a relatively quiet part of its 11-to-14 year cycle by the time the mission launches, but that merely reduces the risk—it does not eliminate it.
The return leg of the trip poses problems of its own. To keep fuel use (and therefore mass) to a minimum, the spacecraft will be on a so-called “free return” trajectory, in which the mission planners rely entirely on gravity to guide their craft through space. That means that, by the time the crew return to Earth in 2020, they will hit the atmosphere at speeds in the region of 51,000kph, smashing the re-entry speed record held by the Apollo crews. It is not clear whether any existing heat-shield technology could protect them. Mr Tito said he was working with NASA to investigate the problem.
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The Economist article says:
"Exposure to such a radiation storm could be lethal. There is, as yet, no generally agreed-upon way of protecting a crew from its effects. The sun ought to be in a relatively quiet part of its 11-to-14 year cycle by the time the mission launches, but that merely reduces the risk—it does not eliminate it."
That's only true if you squint at it a certain way. The "generally agreed-upon way of protecting a crew" is to put mass between them and the Sun. That's the whole "storm shelter" concept. If you have a long spacecraft, you'd point it away from the sun so that the engines, tanks, and other structure is between the crew and the sun. For a really big CME, they'll die, but those are pretty rare events. When dealing with radiation, it's the overall galactic cosmic background radiation that is the thornier problem, because it comes from all directions, although the primary issue is increasing the overall cancer risk rate.
As for the reentry issue, my understanding is that they would take the reentry in two steps, first aerocapture into Earth orbit, then reentry. That's not easy, but it's not the same as taking the whole 51K kph in one bite.
"Exposure to such a radiation storm could be lethal. There is, as yet, no generally agreed-upon way of protecting a crew from its effects. The sun ought to be in a relatively quiet part of its 11-to-14 year cycle by the time the mission launches, but that merely reduces the risk—it does not eliminate it."
That's only true if you squint at it a certain way. The "generally agreed-upon way of protecting a crew" is to put mass between them and the Sun. That's the whole "storm shelter" concept. If you have a long spacecraft, you'd point it away from the sun so that the engines, tanks, and other structure is between the crew and the sun. For a really big CME, they'll die, but those are pretty rare events. When dealing with radiation, it's the overall galactic cosmic background radiation that is the thornier problem, because it comes from all directions, although the primary issue is increasing the overall cancer risk rate.
As for the reentry issue, my understanding is that they would take the reentry in two steps, first aerocapture into Earth orbit, then reentry. That's not easy, but it's not the same as taking the whole 51K kph in one bite.
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