For fifty years, NASA prepared for space missions as if for battle: practice repeatedly what you must do, prepare to be surprised, and have backup plans when you are, because you will be. But now with America’s space future at stake, that principle appears to have weakened, and NASA may have overlooked something crucial.
On March 4, during testimony before a U.S. House Appropriations subcommittee, NASA administrator Charles Bolden was asked about what happens if the Russians pull out of the International Space Station. (Critical ISS modules are Russian, and currently the only way for humans to travel between the ISS and the ground is via Russian Soyuz spacecraft.) Asked by the new chairman, John Culberson, about what would happen in the event that Vladimir Putin’s current belligerency ever led to Russia refusing to fly Americans to the space station, Bolden stated that it would be impossible for either Russia or America to operate the station without the other. Pressed by Culberson about NASA contingency plans, Bolden said “You are forcing me into this answer, and I like to give you real answers,” then adding “I don't want to try and BS anybody.” But, in the end, told the committee, “We would make an orderly evacuation.”
That’s it—we’d have time to pack and turn out the lights.
That’s the wrong answer. But Culberson’s question was wrong too, narrowly focused as it was on Kremlin perfidy. Many scenarios could cripple Russia’s ability to fly crews to the ISS. The Russians could be victimized by technical problems with launch vehicles, suffer diplomatic problems with the Soyuz launch site (which is located in Khazakastan, a country concerned about what’s been happening in Ukraine), be subject to terrorist attacks on ground infrastructure, or suddenly have to cope with age- or human-error-induced crippling of one of their station modules. Exactly what NASA and its other partners would have to do in response to any of these scenarios would deeply depend on the specific nature of the loss of function.
So to learn that NASA has spent no thought on what to do in the face of this wide gamut of possible events is disturbing. Past space disasters—such as Apollo 13’s liquid-oxygen tank explosion, Skylab’s crippling launch mishaps, and the misshapen Hubble telescope mirror—were overcome in large part because space planners had anticipated categories of failures and had then outlined response plans, albeit often with the details left to be filled in as needed.
But apparently not this time, with the most expensive and irreplaceable space station the world has ever seen? Let me suggest some half-baked answers as a starting point.
The problem of getting a US crew to the station is approaching resolution, with operational missions of commercial crew transportation vehicles from SpaceX and Boeing two or three years away. That date is budget-driven and with emergency funding could be moved significantly sooner.
Meanwhile, even if no new astronauts can be sent to the ISS, those already aboard would be able to hunker down and extend their stay significantly. It would bend and even break current medical limits (which have only recently been extended to permit a one-year stay on the station for Mikhail Kornienko and Scott Kelly, who blasted off for the ISS last Friday) but it would be an emergency response.
The remaining safety issue would be the problem of conducting an emergency evacuation in the case that one or both of the two Soyuz spacecraft normally docked at the station were unavailable. Even here, there are conceivable short-term modifications to existing cargo vehicles, such as SpaceX’s Dragon capsule, that could provide an acceptable crew return ability with bare-bones life support.
This would incur significant risks. But they would have to be balanced against the enormously greater risk posed abandoning the station in the face of a breakdown of cooperation between America and Russia. Most of that risk would be in the form of the consequent unavoidable random impact of a million pounds of station debris somewhere on Earth. The station cannot be safely de-orbited into open ocean without the Russians.
Keeping the ISS in orbit, then, would the next major operational challenge.
The station now flies at about 400 kilometers altitude. This is low enough that there is slight but measurable air drag that inexorably lowers the ISS’s altitude, requiring regular reboosts. There are engines for this purpose on the Russian modules, but, whenever possible, reboosts are performed using the engines of docked supply ships, mostly Russian in make but occasionally European as well (although that European series of vehicles has recently finished all their scheduled flights).
Depending on solar activity (which can inflate the atmosphere) it would take perhaps a year or slightly more for the orbit of the ISS to irreversibly decay. Some short-term techniques, such as reducing air drag by feathering the solar arrays would, at significant cost in power generation, extend that lifetime somewhat.
Absent the Russians then, NASA would have to find a new ‘tug’ vehicle—one that could reach the station and dock at place where it’s safe to apply thrust—within the space of a year. It’s probably the long pole in the “Save the ISS” tent. (Bear in mind that it was originally thought that the space shuttle would be flying in plenty of time to reboost the Skylab space station. That didn’t end too well for Skylab.)
The challenge is that the ISS is so massive that currently available American upper stages can’t carry enough propellant to push the station into a higher orbit. Perhaps a European tug, thrown together from spare parts, could be readied in time. Perhaps the magicians at SpaceX or other commercial space shops could whip together a series of smaller tugs, one after the other.
Or even more original ideas (desperate ideas for desperate times) might work out, if thought about and ground-tested early enough. There are proposals for continuous-thrusting ion engines, some well into bench testing, for example. Surely it would be prudent for NASA to survey and catalog these long shots before the crisis actually arrives?
There’s even a crazy idea reminiscent of the Russian tale of winter sleigh travelers pursued by wolves, stretching their lives by tossing the smallest guy out of the sled. In this scheme, ISS astronauts would detach a station module or two (at enormous effort in terms of spacewalks). Each module would be tied to a long Kevlar tether to dangle down 100 km beneath the station, and then the tether would be cut. The module would fall to a controlled atmospheric burnup while—thanks to conservation of momentum—throwing the station significantly higher.
Without a real propulsion system, however, the ISS wouldn’t be able to make debris avoidance burns, needed several times a year to reduce collision hazards. So for longer term operations, at some point a new permanent thruster module would need to be added.
No question this challenge would be hard. But to hear a NASA leader tell the world that that’s a reason not to even try—not to take a risk, even with volunteers—is a reversal of time-honored toughness, competence, and ingenuity that gave us the Moon, and given us the potentially-threatened space outpost that is paving the way outwards far beyond it.