HOUSTON ?? NASA will shortly announce plans to double the mission duration of some astronaut expeditions to the International Space Station, NBC News has learned. Beginning as early as 2015, some of the astronauts and cosmonauts sent into orbit will remain there not the usual six months, but for a full year.
In Houston last week, NASA spokesman Kelly Humphries acknowledged that the project was under study but said it was still only a proposal. "All we can say is that we are exploring possibilities," he said in an Aug. 21 email. "There have been no formal decisions made, and it is premature to speculate what the outcome might be."
But sources familiar with NASA's plans say the preparations for such a mission are much more advanced than this description suggests. Specific mission dates and crew candidates are already being assessed. The sources discussed the plans on condition of anonymity because they were not yet due to be announced publicly.
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Speculation about the specifics as well as the general mission overview is entirely justified, due to its potential significance to the future of human space activity. That is because the extension of zero-G exposure will be aimed mainly at measuring the potential physiological impacts of spaceflights long enough to accomplish the human interplanetary missions envisaged beginning in the 2020s.
It is this new mission that will coincidentally open up the opportunity for the Russian space program to resume selling "space tourist" tickets into orbit, as reflected by the recent reports about a potential flight for British singer Sarah Brightman .
The Russians halted these space passenger missions three years ago as the International Space Station crew size increased from three to six and NASA space shuttle missions drew to a close. Due to the retirement of the shuttle fleet, every ticket on every three-seat Soyuz launch had to be used by a long-term station resident. There were no longer any spare tickets for visitors, even though there are now four Soyuz launches per year instead of the previous two per year.
Having some station residents "stay over" their normal rotation to Earth will again open a spare seat, perhaps two. The Russians are said to be enthusiastic about the idea, with tickets going at a price upwards of $35 million each.
Vitaly Lopota ? the president of Russia's Energia rocket company, which is in charge of building the Soyuz craft for Russia's Roskosmos space agency ? confirmed on Monday that there have been requests for space passenger seats. "If there is a team, we'll start work, but besides a team, funds are needed," Russia's Interfax-AVN news service quoted Lopota as saying. "We need the resources before the end of the year."
Lopota said the short-term tourist trips would be easier to organize if the 12-month mission plan was put into effect.
On the American side, the plan could have election-year significance. It could help the White House underscore the seriousness of its commitment to American leadership in human spaceflight beyond low Earth orbit, where the space station operates.
So far, NASA's strategy for exploration beyond Earth orbit has been mostly just talk and long-range planning for bigger rockets. Battles over booster designs and budgets, and even an unresolved issue as basic as selecting an actual destination in space for future astronauts, have contributed to the impression that little or nothing is happening.
That may change. Although NASA turned down the idea of staging 12-month orbital missions eight years ago , the enthusiasm over the recent success of NASA's Curiosity lander on Mars has now created a public atmosphere supportive of such bold projects, sources within NASA have told NBC News.
Base motives for idealistic missions
Justifying this major advance in human space exploration through appeals to cash flows and election-year politicking may seem a bit tawdry, but it?s really more the rule than the exception in history.
After all, the greatest exploratory expeditions of human history have often been motivated at least in part by the quest for wealth and power. Whether it was the Columbus voyages, or the ?Corps of Discovery? of Lewis and Clark, or Project Apollo, the primary motivating factor that led to getting the funds was "What?s in it for me?"
But whatever the base desire for short-term benefits ? many of which never actually materialized ? such activities have delivered profound and widespread gains in acquired knowledge and cultural inspiration. Usually, the results more than justified any short-term financing deals.
So it should come as no surprise ? and should be no cause for shame ? that as Russia and the United States together gather their energies to launch forth on long space endurance runs, the motives foremost in their governments? minds are all too mundane.
So what? These flights, first to 12 months and then conceivably to 18 or even 24 months or longer over the next decade, are the first practical steps on the ladder of capabilities rising toward human interplanetary flight. Together with life-support hardware already in advanced testing on the space station, such a program is critical for finally getting out of low Earth orbit.
Long-term precedents
Yearlong spaceflights have been made before, with no indication of significant medical issues. One Russian crew in 1987 spent 366 days in space, and in 1994-1995, Valery Polyakov spent a total of 14 months aboard Mir. But these were record-seeking one-offs with no follow-up.
What's more, space medicine specialists around the world have long questioned the quality of the Russian medical data from those flights. Cosmonauts later admitted faking a lot of the test results, for sport on boring missions. In the 1980s, even the Soviet space medicine establishment relied on heavily instrumented Skylab medical baselines, even though their own missions had flown twice as long, then even longer.
Even the current standard "duty tour" of six months in space is an operational accident with no rational medical basis. NASA doctors preferred about 4 months as the optimal mission duration, when station astronauts were transported on shuttle flights. Cosmonauts agreed. They reported growing fatigue in the final month or two of their half-year space sojourns.
A six-month tour is purely a result of the design lifetime of the Russian Soyuz ferry craft, with the limit flexible enough to push up to seven months in a pinch. After that, chemical decomposition of propellants in the landing capsule could potentially reach levels rendering the fuel unusable for guiding the craft's re-entry.
In addition, NASA doctors have developed another arbitrary stick-in-the-spokes for serious long-term missions. An arbitrary upper limit on cancer threat from radiation exposure essentially limits American astronauts to no more than about a year total spaceflight time.
An American astronaut who was yanked off a space station flight due to "excessive" radiation exposure from a ground medical procedure bitterly told NBC News: "It?s a sham standard." He explained: "It doesn?t reduce the cumulative health impact, since cancer threat is linear with duration. It only redistributes it."
The astronaut expressed the opinion that crew candidates be given the option of accepting or declining the hazard, balanced against their own individual medical histories and career plans. And to make these longer flights, his advice will need to be taken by NASA doctors, although it would be too late to be of any help to himself.
Commuting the Earth-space route
The actual scheduling of a 12-month mission onto the existing traffic pattern to and from Earth orbit is surprising complex. The pattern of the current crew transport to the space station is well-established, and there is little likelihood of any significant modification to it before the beginning of commercial crew transport in 2016 or so.
Four Soyuz spacecraft are launched every year, each carrying three crew members. The commander is always a Russian cosmonaut, and one crew member is always an American astronaut. The choice for the third crew member alternates between a Russian cosmonaut and an "international partner" such as a Japanese, Canadian or European astronaut.
With six people aboard the space station, crew rotation occurs when the three members of a returning crew get into their own Soyuz and head back to Earth. This leaves only three crew members on the station for several weeks. The staffing returns to six when a new crew is launched.
That full staffing reflects a careful plan worked out by the international partnership to allocate three seats to Russia and three to the "U.S. segment." NASA allocates one of those three seats to the astronaut from Japan, Canada or Europe.
What this means is that Russia has a second Soyuz seat ? the one they are allowed to "sell" ? only every other Soyuz launch. And when they do, the third seat is occupied by an American astronaut.
To send one Russian and one American on a 12-month mission requires careful planning. The crucial choice is dictated by the fact that the six-months-along mission, the one that would normally be used for the rotation of the original crew, must have had two Russian seats on it. One would be for the pilot, and one would be available for Russia to sell to a paying customer. That means that the third seat would, by rights, be occupied by an American astronaut.
This ?stayover? mission cannot wait for the previous six-month Soyuz to land ? since two of the previous Soyuz's crew members intend to remain in orbit. So the Soyuz must launch while the earlier two Soyuzes are both still docked to the station.
There are four docking ports for Russian spacecraft, so mechanically this isn?t too difficult. It was already done once, in 2009, for the first crew rotation after the station permanent crew size went from three to six. But there are tricky issues with three docked Soyuzes, including safe emergency evacuation procedures for all three spacecraft. These issues need to be thoroughly worked out.
Who gets the short straw?
An even trickier issue has to do with the fact that the Russian pilot of the "stayover" Soyuz will be replacing the Russian pilot of the Soyuz-before-last, so that the pilot on the station can return after six months. But the two crew members who accompanied that pilot into space six months earlier will be staying aboard, headed for their full-year tour. So, two of the crew members of the "stayover Soyuz" will switch over and accompany the departing pilot on the earthbound Soyuz.
Now here?s the tricky part. One of those two short-term fliers, in what normally would be the "Russian seat," can be the cash customer. But the other would have to be an American astronaut. That astronaut would be forced to return to Earth after only a short mission, perhaps spending less than two weeks in orbit.
Why should NASA have to pay full launch price ? around $65 million ? for a mission that will last only a tenth as long as the standard duty tour?
If the Russians let NASA out of its contracted plan to use the seat and offer it to a commercial space passenger, the revenue from that seat would be around $35 million ? half of the rate that NASA would be charged. That would represent a financial loss for Russia that could be as nearly great as the entire profit from the first ticket sale.
It would end up being a wash. It would mean selling one seat to NASA for $65 million, or two seats to two commercial space travelers for around $35 million each. From the Russian point of vew, the American side must pay full price for its truncated space stay, or Russia makes virtually no money at all for the entire deal.
There is a variety of alternative seating schemes, as well as the possibility of staggering the Russian and American long-termers on successive launches. NBC News has learned that the "staggering" option is being seriously considered. It will be interesting to observe how both sides dance around these practical matters in designing the actual mission.
Whatever the arrangements turn out to be, the rationalizations and compromises will soon be forgotten as part of the nitty-gritty, real-world wheeling and dealing to extract maximum national benefits from the opportunity. What won?t be forgotten is the result: the first major sustained advance in human spaceflight endurance in two decades, an advance that will finally dispel enough dragons and "unknown unknowns" to open the door to deep-space journeys.
Best of all, the opening will have been achieved methodically and prudently, without reliance on the gung-ho adventurism and deliriously wishful thinking of "Mars mission" crusaders of the past. The odds of avoiding disaster are so much better this way.
More about long-duration spaceflight:
NBC News space analyst James Oberg spent 22 years at NASA's Johnson Space Center as a Mission Control operator and an orbital designer. He is the author of several books on space history and space policy, including "Star-Crossed Orbits: Inside the U.S.-Russian Space Alliance."
Source: http://www.msnbc.msn.com/id/48807002/ns/technology_and_science-space/
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