Before
David Wolf got his chance to fly to Mir, the risks had become more than
statistical probabilities. Alarming events had happened on the Russian
space station. Wolfs predecessors, Jerry Linenger and Mike Foale, had
faced fire and collision. The U.S. Congress, the worlds news media,
and even former astronauts now questioned the wisdom of sending up another
American to Mir. Wolf should not go, some said, because Mir was too
old and too dangerous. NASA and the Congress ordered extensive reviews.
The buck finally stopped at Wolfs two bosses: Shuttle-Mir Program
Manager Frank Culbertson and NASA Administrator Dan Goldin. Each considered
the situation from his own perspective. Culbertson drew on his experience
as an astronaut and his sensibilities as Wolfs friend. Goldin focused
on safety and the missions importance to the nation. Culbertson and
Goldin used every minute of the time that they had, which was all the
time that they needed. Goldin announced the recommitment to fly Wolf
on the morning before the launch of Atlantis.
On September 25, 1997, when Wolf rose spaceward to begin his 128 days
in orbit, he looked forward to doing the hard, sometimes grimy duty
onboard Mir.
He later noted that his predecessors had "done a great job fighting
the alligators and it was now time to drain the swamps." He also
hoped to make an exciting spacewalk alongside a Russian extravehicular
activity master.
Wolf flewand he flew with gusto and affability. In his own mind, he
was not flying in spite of the risks. Nor was he flying cavalierly because
of them. Wolf flew to Mir because he had carefully weighed his missions
risks. He had considered its value to humanitys progress. And, like
all astronauts, he knew that he wanted those intangible, personal rewards
that would come from an historic, out-of-this-world opportunity. He
said later, "Personally, I was sure I was going the whole time,
and I never had one moment of second thought
. I carefully went through
the issues, and I was absolutely comfortable stepping through the various
scenarios and responses
. In fact, I became more convinced that we should
continue the more familiar I became with the details." He was confident
that others would ultimately feel the same, and he stressed that it
was exactly at this timewhen things were difficultthat "we should
demonstrate the strength of our partnership with the Russians."
David Wolfs background and personality were suited to long-duration
spaceflight. He was an astronaut, a physician, a researcher, an inventor,
and an aerobatics pilot. Born in Indianapolis, Indiana, in 1956, Wolf
had grown up to become a gregarious Jack-of-all-trades who enjoyed both
theoretical thinking and skinned-knuckle mechanics. While attending
medical school at Indiana University, he worked at the Indianapolis
Center for Advanced Research, specializing in medical ultrasonic signal
processing. He completed his internship and, in 1983, joined NASAs
Medical Sciences Division at the Johnson Space Center in Houston. He
directed the development of the space bioreactor that was to see service
on Mir. He also worked as chief engineer in charge of the design for
the space station medical facility. Wolf became a NASA astronaut in
1991 and flew as a crewmember onboard STS-58, a medical research mission.
When
tapped for the NASA-6 increment on Mir, Wolf was already in Russia,
training as the backup to Wendy Lawrence. He inherited her slot when
she was disqualified due to the new stipulation that all Mir astronauts
must be extravehicular activity-ready and fit within the size limits
of the Russian Orlan suits. For Lawrence, this was yet another "too
short" situation, similar to the one that had bumped Mike Foale
into the role of flying on NASA-5. For Wolf, it hurried his trip to
the space station. He had been planning on flying last, after Lawrences
increment.
Besides delivering Wolf, the STS-86 mission included the delivery of
a new motion control computer and a solar array cap. On the final day
of docked operations, Wolfs new crewmatesMir-24 Commander Anatoly
Solovyev and Flight Engineer Pavel Vinogradovinstalled the new computer
and, shortly before Atlantis docked, they activated Mirs gyrodynes
to help keep the space station stable.
During his residency aboard Mir, Wolf wrote a series of "Letters
Home." In one of them, he related the undocking: "The Space
Shuttle Atlantis hatch shut, its docking hooks released, and
its translational thruster jets fired. I could clearly see Jims [Wetherbee]
and Mikes [Bloomfield] faces peering through the Shuttles overhead
window. We waved. Mikes other hand moved, and another minus Z-axis
translational pulse increased our rate of separation. Another volley
of bright orange rocket engines flashed against the dimly Moonlit Earth."
Atlantis
pilot Mike Bloomfield held position for nearly an hour until the two
spacecraft moved into orbital daylight. Then, Bloomfield did a slow
fly-around of Mir while his crewmates took video and still photos of
the entire station, concentrating on the damaged Spektr module. In an
attempt to find the hole in Spektrs hull, Commander Solovyev opened
a valve to pump air into the module, hoping that the Atlantis
crew would spot debris being vented out to space. Mir Flight Engineer
Pavel Vinogradov saw a particle floating away from the module, but he
said he couldnt detect the exact location where it came from.
As
Atlantis left Mir on its journey back to Earth, Wolf already
felt at ease in his new orbital home. STS-86 Commander Jim Wetherbee
later recalled how Wolf had ended every telecommunications session while
the Shuttle was still docked. According to Wetherbee, Wolf told the
ground controllers, "Now, be careful down there. Youre awfully
close to the ground. You dont want to get hurt." Wetherbee thought
this "was a great way to think about risk." Wolf was "up
there, floating around in what astronauts tend to think of as a relatively
risk-free environmentalthough there are some risksbut hes telling
the people on the ground, Dont worry about me. You take care of yourselves,
and Ill be okay up here."
Along with his new crewmates, Wolf started work on a variety of projects,
including the three-dimensional biotechnology tissue culture, optical
properties monitor, and Canadian protein crystallization experimentthe
latter designed to analyze the crystalline structure of 32 proteins
in an effort to improve drug development and design.
David Wolf also explored his new world-above-the-world; and he wrote
that in ways it hearkened back to the age of classic science fiction.
"The central command post has keys that look like worn ivory. Leather
shrouds serve where plastic would now be chosen. The metal machining
is recognizably Russian, and of the highest quality. Its overall character
brings forth the image of the time machine from H.G. Wells classic."
Wolf
mentioned "tables with things on both sides," "a bicycle
with no seat," and "a set of heavy tools held in place by
rubber bands." He also described the Soyuz escape capsule as "an
amazing vehicle which comes straight out of Jules Verne. An absolutely
beautiful piece of handcraftsmanship. Very ì˛ÚÌ˚È
(OO yoot niy) [cozy] with wood-grained control handles and those beautiful
ivory keys again. As I write, it waits, fueled and ready to bring us
back to Earth."
Mir
was, in ways, "cozy," according to Wolf; but in other ways,
it was a mess. Wolf later related how he immediately offered to take
full part in the housekeeping on Mir. "The first day, after the
Shuttle left, I noticed Pavel cleaning up with rags
a large amount
of condensate on the heat exchangers to the Elektron unit
. We had troublesin
fact, a complete failure of the condensation-removal system." Behind
panels, "large condensate globs, bowling-ball size or beach-ball
size sometimes
of gooey, slimy, ice-cold fluid [were]
starting to
track down the structure and into the wiring."
Wolf
went up to Vinogradov and said, "You never have to do this again."
According to Wolf, the flight engineer "looked at me kind of funny.
I said, Im doing it. Dont worry. Youve got better things to do up
here. I didnt realize what I was getting into, because it took anywhere
from four to eight hours a day, the rest of the mission, every single
day except a few. Nevertheless, I think that went a ways to their putting
me on the team
. Theres no small or unimportant job on the space station.
All of it has to get done, and that was the best thing I could come
up with to free up their time." And, to become part of the team.
On
October 8, a new Progress resupply ship successfully docked to the stations
Kvant-1 module. The spacecraft carried 1.7 tons of supplies for the
station, including science equipment, fresh food, 100 liters of water,
and clothing and other personal items for the crewmembers. The Progress
also brought up a motion control system computer to serve as a backup
to the one that Atlantis had just delivered.
In a "Letter Home," Wolf described the Progress docking with
Mir. "It was almost eerie to see the robot ship loom in out of
the darkness. The view from Anatolys [Solovyev] tele-operated pilot
station was as seen by the cargo ship, closing in on this amazing space
station. Its computer mind correcting for errors in the cross-hairs
on the docking target, just as Anatoly would have done himself. It behaved
almost human. Anatolys hands were lightly poised on the remote control
sticks, ready to manually take over at the first sign of bad decision-making
by the computer pilot.
He and Pavel [Vinogradov] checked approach speeds and positions from
the console. In their minds they had transported themselves and were
sitting in the cargo ship
. As I watched their moves and words [and
saw] how confidently they worked together from training and experience,
my few thoughts of what happened to Mike Foale a few months ago were
quenched." Then, "Thunk," the Progress docked. "It
hit pretty firmlywhich is normal. No pressure sensations in my ears.
Docking mechanism properly engaged. The silence of tuned nerves was
broken by laughter and handshakes. Supplies had arrived."
Wolf collected data during the undocking of the old Progress and the
docking of the new Progress for the Mir structural dynamics experiment.
This experiment measured forces exerted on the Mir by events such as
vehicle dockings and thruster firings, and even the crew exercising.
The crew performed routine maintenance on various Mir systems. They
replaced batteries in the Base Block and in the Kvant-2 module with
new batteries brought up on Atlantis; and they rearranged other
batteries to ensure that the batteries were fully charged. They worked
on the urine recovery system that provided water for systems. And, Solovyev
and Vinogradov began their preparations for a second planned intravehicular
activity (IVA) into the Spektr module. This IVA was designed to recover
additional power from Spektrs functioning solar arrays by restoring
the arrays ability to swivel and track the Suns light.
The crew installed a new control unit on the Elektron oxygen-generating
unit in the Kvant-2 module. The Elektrons in both the Kvant-1 and the
Kvant-2 modules had been running simultaneously to increase the oxygen
in the station in preparation for the IVA. In the Kvant-2 module, the
crew installed a new drive unit on one of the gyrodynes. On Mir, eight
to nine gyrodynes were needed to maintain attitude control; Mir was
now operating on 11 gyrodynes.
After three weeks onboard Mir, Wolf reported life as "quite good.
The air is extremely fresh and clean. Anybody who wants to work hard
can find a lot to do up here. You dont need to be a rocket scientist
to stay very busy." He said he had taken on the personal goal of
keeping the air filters clean. "I plan to leave this station a
bit better and cleaner than when I came."
Of course, the August collision with the Progress vehicle had severely
damaged some of that equipment; and on October 20, Solovyev and Vinogradov
conducted an IVA, suiting up to enter the vacuum of the Spektr module.
During the grueling six-hour, 38-minute IVA, the cosmonauts had to be
careful not to get tangled up in the disorder that was now filling Spektr.
They were able to connect two power cables that increased solar power
to Mir by 15 to 30 percent. Wolf stayed in the Soyuz capsule during
the IVA, monitoring Soyuz systems and conducting Earth observation photography.
The crew spent the rest of the week powering up Mir systems and modules.
American democracy was powering up on Mir as well. In late October,
Wolf cast the first American election ballot from orbit, using an electronic
mail system developed among Johnson Space Center, Mission Control-Moscow,
and the County Clerks Office in Harris County, Texas. In an interview
from orbit, Wolf said about his voting, "Its important. It makes
me feel attached to the ground like I didnt feel before.
I feel its more important here in space even than I did on the ground.
Votings important to all of us. Its what puts the people in charge."
Ironically, Russian democracy had beaten America into space. In June
1996, Shannon Lucids crewmates Usachev and Onufriyenko had voted in
a Russian presidential election.
In
early November, Solovyev and Vinogradov conducted two more extravehicular
activities. They replaced an aging solar array on the Kvant-1 module.
The new array had been stored in a compartment on the Mirs docking
module since it was delivered on the STS-74 Shuttle-Mir docking mission
two years before. Solovyev and Vinogradov also installed a device on
the outside of the module that would enable the crew to hook up an additional
Vozdukh carbon dioxide removal system for the station.
During the first extravehicular activity, Vinogradov commemorated the
40th anniversary of the launching of the first Sputnik satellite by
manually deploying a replica of the Sputnik. This effort was part of
a joint project between Russian and French high school students. Wolf
videotaped the event. He said later, "The first thing that went
through my mind was, God, Ive got to get this video camera on it and
get the picture right. But, after that, when I reflected on it40 years
is how long its been. I believe it was October 4, 1957, when the first
satellite was launched by the Russians. And, you just look at where
weve come in that amount of time. It was not much more than 40 years
before that [that] the first airplane flew. And, I thought a lot about
the pace of technology and how our lives are changing, and how NASA
needs to be a part of designing our future way of life just as it was
a large part in creating our current quality of life."
The extravehicular activitys final task for Solovyev and Vinogradov
was to retrieve a panel from an old and disconnected solar array on
the side of the Base Block. The panel would be returned on Endeavour
on the STS-89 mission in January to be analyzed for micrometeoroid damage.
The cosmonauts had a problem repressurizing the Kvant-2 modules exterior
airlock after the first spacewalk. For the second extravehicular activity,
they used an interior compartment as a backup airlock. Then, they tightened
clamps and latches around the circumference of the leaky hatch to hold
pressure, the problem thus appeared at least partly solved. This was
another example of the differences between short- and long-duration
spaceflights. On space stations, many repairs have to be done "on
the fly" instead of being brought back to Earth, as they are on
the Space Shuttle.
David Wolf later wrote about his duties during one of the extravehicular
activities. "My job was issuing the computer commands to the new
arrays deployment mechanism, and something didnt work. Now, we were
off nominal and out of the checklist, [and] going fast, in Russian,
and with [only a] short time left on the spacesuit carbon dioxide scrubbers."
In coordination with Mission Control-Moscow, the Mir crew improvised
manual procedures to command the solar array deployment. As Wolf wrote,
"Retract two steps. Disable motion quick. Its jammed. Try to re-extend
by one step. What are the motor power indications? Is there a center-section
deployed indication? We need to reinitialize the sequencer." And,
all of this was done, Wolf wrote, "as fast as my fingers could
press buttons and in Russian." After the experience, Wolf said
he now had an answer for that repeating question, "What has been
your toughest moment so far in the mission?"
The
weeks EVAs were Anatoly Solovyevs 13th and 14th spacewalks in his
five tours of duty on the Russian outpost. He had now conducted five
spacewalks during Mir-24. Vinogradov, on his first spaceflight, had
now made four spacewalks. With the two extravehicular activities behind
them, the cosmonauts were given the weekend off to relax before resuming
scientific research and routine maintenance activities.
Wolf
was beginning his seventh week as a Mir crewmember. In an interview,
he said, "I love space, and Im getting a good dose of it here.
Its funeverything from floating and flying to handling floating equipment.
Its a beautiful view. You never get tired of looking at the Earth."
Wolf reported that when sleeping, "I dream that Im in space. Last
night, in fact, I dreamed I was with my friends and we were playing
volleyball, and it was a wild game." While awake, Wolf said, "Im
surprised every time. I look up and I wonder how Ill reach thatand
then I realize I can just float up and get it. It takes a moment for
that to register, so Im not fully used to it. But, I get better at
it every day."
Wolf also realized that he would have to re-accustom himself to a changed
Earth when he went home. He said that after a Shuttle mission, "The
likelihood of things changing in a drastic or significant way is small.
Heck, you barely miss much of your mail. But, when youre gone for months,
you really start to lose touch a little bit with the Earth."
He was starting to feel like Mir was his world, and the Earth was beginning
to feel a little "dreamlike." It was important "to be
able to keep in touch with itvisually and through any media and means
that you can." Video movies were particularly effective. They had
more emotional impact under those remote conditions.
On November 13, Mir suffered a temporary power loss during a test of
the newly installed solar array on Kvant-1. This caused the shutdown
of the motion control system computer and interrupted Wolfs scientific
investigations. The crew transferred fully charged batteries from the
Kristall module to the Base Block, and they restored power to five of
the 11 gyrodynes that provide attitude control to Mir. However, the
batteries alone could not support the many hours required to stabilize
the station. So, throughout the weekend, the three crewmates alternated
shifts to monitor systems; and whenever Mir drifted into an attitude
favorable for solar energy collection, they temporarily powered up the
battery chargers.
Meanwhile on Kvant-2, a slow air leak persisted in spite of the efforts
by Solovyev and Vinogradov during the second spacewalk. The situation
posed no danger to the station, as the hatch door on the instrumentation
compartment behind the airlock provided an air-tight seal.
David
Wolf was now midway through his four-month mission. In an interview,
he said that while the Russian space station was like a "fixer-upper"
car in which things broke down, "you can trust it to take a long
trip." He said that Mir was clean and in good shape. Then, he joked,
"It could use some new carpet." Wolf also compared doing science
on the Space Shuttle and on a space station. "One difference is
in the laboratory," he said. "Right now, for instance, on
the computer display, we are watching a laser image of a crystal as
it grows. You can see the sides of the crystal as microgravity helps
it grow, and we get to send these images down to the scientists on Earth.
We then listen to what they say and we make decisions and change what
we do in response to the results. Its more like a laboratory would
be run on Earth; whereas on the Shuttle, its kind of a sprint race.
You get up there [in orbit] and, in 8, 10, 12, 14 days, just do all
you can. Here, we can plan and change the plan during the mission."
The American astronaut aboard Mir sometimes worked as a scientist and
wrote as a novelist. In a letter, he described a view of Earth. "Ghostly
outlines of continents just illuminated by the half Moon. At an unfelt
five miles per second, we blow out of the Earths shadow and into the
harsh unattenuated sunlight. Solar arrays alertly take notice and rotate
precisely into position to capture a bit of this fortuitous energy.
We blaze over that moving line on the Earth that separates night from
day. The dominant features on the planet below are two tectonic plates.
One holding the Tibetan Plateau and the other, India. The plates are
clearly smashing together, incidentally elevating the Great Himalayan
Mountain Range. Eyes now adjusting, looking real close, there, snow-covered
Mt. Everest and Katmandu. Its a rare clear day over France, England,
and Italy. Hazy, even smoky, into China and southern Siberia. Some large
smoke plumes, a lot of forest clearing going on there. Just ahead, to
the east, the incredible blue Lake Baikal, perhaps the biggest lake
in the world. Set like a gemstone into the Earths crust."
During the week of November 21, the crew experienced another power-down,
this one resulting from a malfunction of the refurbished motion control
system computer that had been brought up on STS-86. They replaced the
computer with a new one that had arrived on a Progress. Wolf later remarked
that the two periods without power, of roughly 48 hours each, "offered
a unique perspective of spaceflight." With no systems operating,
with no fans and no pumps going, "the incredible quiet of space
was experienced. From the dark, quiet ship, the surreal experience of
space was ever more intense."
Commander Solovyev was intent on restoring Mir to top condition; and
soon after power was regained, the cosmonauts installed a new Vozdukh
carbon dioxide removal system in the Mir Base Block to serve as a backup
to the unit that was currently functioning. An extensive amount of drilling,
sawing, and wiring was required to fit this large system behind the
stations panels.
Wolf helped his crewmates with the systems activities and repairs,
and he continued his science program. His favorite investigation was
the Three-Dimensional Biotechnology Tissue Engineering Experiment, perhaps
because of his involvement in its early development before becoming
an astronaut. He later echoed other Mir residents when he said, "It
felt good being back in the laboratory." The combination of activities
led to very long workdays and, Wolf noted, "boredom was not a factor
for this crew."
During December, Solovyev and Vinogradov spent time troubleshooting
leaks in a backup cooling loop aboard Mir. They also released additional
oxygen into the station from the tanks aboard the Progress, and they
loaded refuse into Progress for its planned jettison from Mir before
a new Progress resupply ship arrived. Christmas was approaching. The
new Progress brought gifts from home as well as a small Christmas tree
and traditional candy from the Red October candy factory near Moscow.
The objects assumed that characteristic intensity typical of long-duration
spaceflight.
The NASA-6 resident worked at measuring bone loss during long-term
spaceflight. Studies had shown that long-duration exposure to microgravity
causes a gradual loss in total bone mineral, a condition that mimics
osteoporosis, which afflicts many older people. Wolfs work with this
involved critically timed injections of isotopes, many blood draws,
careful dietary logs, and urine collections. By learning more about
bone mineral loss and recovery in space veterans, researchers hoped
to develop better treatments for those people who suffer bone disorders
on Earth. Wolf also conducted an investigation to study the human bodys
ability to produce antibodies in microgravity in response to vaccination.
Previous research had indicated that some of the human bodys immune
responses appear to be suppressed during long-duration spaceflight.
In this case, the vaccination against pneumonia demonstrated normal
antibody production.
In
early December, Wolfs flight received a five-day extension with the
adjustment of the launch date of Endeavour (STS-89). The joint
decision by U.S. and Russian officials to delay the launch of STS-89
enabled the Mir-24 cosmonauts to complete three spacewalks planned for
late December and early January. The delay also allowed Wolf additional
time to complete his science program on Mir.
In a pre-holidays interview on December 12, Wolf discussed how he was
feeling onboard the space station. "After about a month, I was
feeling extremely good; and after two months, I realized just how good
you could feel in space. And, Im feeling better and better every day,
enjoying working in space more and more, learning to handle the difficulties
of working in space better and better
although I miss home more and
more." His hopes for the New Year included a world at peace, in
which all the bordersinvisible from spacewould "mean less in
terms of wars and the problems we have, and more in terms of helping
each other." Commander Anatoly Solovyev spoke of meeting the New
Year in a way "that cannot be duplicated on Earth
with the Australians
first," because Australia was just west of the International Dateline.
He said, "A lot of people come out and want to talk to us on the
[ham] radio and to wish us the best of wishes. This is a rather difficult
time for us in that regard, but in general its also very pleasant.
There is, apparently, no champagne here for us to celebrate the New
Year, although there is, of course, the desire."
Wolf was asked about the possibility of his making a spacewalk with
Solovyev. He answered, "You know that since I was nine years old
Ive
wanted to do a spacewalk
. We trained intensely before the mission.
I continue to train onboard. The spacesuit is in itself a spaceship.
It has all the fundamental systems of a spacecraft itself, and in a
mission this long you need to study on orbit
. Ill look forward to
taking a lesson from this fine spacewalker."
On December 17, the Progress resupply vehicle, filled with trash for
disposal, undocked from Mir and was commanded to stop a short distance
from the station. A small German-built robot camera, called Inspektor,
was deployed from the Progress for its first flight test. Inspektor
was supposed to first circle the Progress to test its maneuvering system
and navigational capability. Then, on computer command from the Mir
cosmonauts inside the station, Inspektor was supposed to approach Mir
and place itself in an elliptical orbit around the orbital outpostto
become, in effect, a satellite of a satellite. But, Inspektors star
tracker guidance system overheated; and Mirs crew reported that, through
binoculars, they could see it was pointed in the wrong direction. The
robot camera on Mir was abandoned after a malfunction. Russian flight
controllers had to stop the experiment. Inspektor was allowed to drift
away from the space station to later burn up in Earths atmosphere.
That disappointment didnt affect the Mir crews overall sense of accomplishment.
Wolf wrote, "The whole team is really hitting its stride right
now. This is what the space station era is all about. Taken together,
the little efficiencies turn a 16-hour day into, say, 11. That sure
means a lot at midnight when you want to float back and appreciate the
adventure. Tolya [Solovyev] and Pasha [Vinogradov] are master craftsmen
as they handle this ship. Occasionally Tolya, flashlight in teeth, will
disappear behind a wall panel, tools and parts in tow. Hours later,
as the sounds of drilling and wrenching subside, he emerges."
The
holidays passed happily, but New Years Day reminded everyone that things
could always change onboard Mir. The motion control system computer
failed again; but, because the station was in a good attitude at the
time of the incident, no Soyuz jet firings were required to stabilize
it. The batteries were also in good shape, and no damage was caused
to any systems due to shut down. However, during the recovery of the
computer, all but the Base Block and the Kvant-1 modules were powered
off as a conservation measure. The new Vozdukh carbon dioxide removal
system scrubber in the Base Block was also shut down briefly. The crew
turned off both Elektron oxygen units, and they used oxygen-generating
candles and oxygen from the Progress vehicle until the Elektrons were
reactivated.
The entire crew also had to work on replacing a cooling system pump
to keep temperatures in Priroda and Kvant-2 at comfortable levels. Temperatures
throughout the mission ran well into the 90s. Indeed, throughout the
entire Shuttle-Mir Program, conditions onboard Mir were hot and humid.
However, they were well-tolerated by the crews, who dressed mainly in
shorts and T-shirts.
On January 9, Anatoly Solovyev and Pavel Vinogradov conducted a 5-hour
spacewalk. They examined and photographed the leaking airlock hatch
on the Kvant-2 module, and they retrieved NASAs Optical Properties
Monitor Experiment. Mir Astronaut Jerry Linenger had installed this
experiment on the docking module during his extravehicular activity
nine months earlier. Wolf monitored the spacewalk from the Base Block,
and he photographed and videotaped the work conducted outside by his
crewmates.
Later that week, finally Wolf had his own turn to try spacewalking.
He ventured outside Mir for four hours with Anatoly Solovyev, the world
record holder. Among other duties, Wolf sampled areas of Mir with a
spectrometer that gauged the impact of the space environment on the
surface of the space station. Wolf later called his spacewalking experience
"spectacular."
However, during the spacewalk, Wolfs spectrometer had a failure in
its display, requiring intense coordination with Vinogradov inside Mir.
As Wolf and Solovyev attempted to reenter Mir, the external airlock
refused to make a totally airtight seal; and the atmospheric pressure,
about 20mm of mercury, was too high for the spacesuits cooling units
to operate but far too low to allow de-suiting. The two spacewalkers
were forced to retreat into the emergency backup airlock, and the high
workload in the absence of cooling led to a rapid increase in their
suits internal temperatures. The airlocks shape, combined with the
fact that the suits remained stiff in the fully pressurized state, required
the two partners to depend on each other to connect the backup cooling
umbilicals. The "off-nominal" spacewalk served as further
proof that multinational crews could work together in real time, in
multiple languages, and on complex operational tasks.
Wolfs four months in space came to a close in January 1998 when Endeavour
(STS-89) launched on January 22 and traveled with Andy Thomas, the final
NASA Mir astronaut, to the space station Mir.
Right
to the end of Wolfs increment, challenges persisted for the Mir-24
crew, and the crew persevered in meeting them. Although Wolf and his
Russian crewmates had essentially met for the first time in spaceand
had not trained togethera theme of teamwork and mutual respect characterized
the mission. During the final two weeks, the Russian e-mail system went
down altogether. The crew depended on this link for all written information
from the Mission Control Center-Moscow. The crew now relied completely
on verbal communications passes, which at this point occurred about
five times a day for about eight minutes each time. The large amount
of technical information transmitted in these passes severely curtailed
all other forms of communication. As a result, Wolf did not hear about
Earthly events, such as space pioneer John Glenns assignment to a Shuttle
flight, until after Endeavour had docked when a reporter asked
him for his reaction to it during a press conference. Surprised, Wolf
turned to Shuttle Commander Terry Wilcutt for confirmation.
David Wolf returned to Earth on January 31, 1998. During his time on
Mir, Wolf completed 36 scientific investigations in six disciplines,
including biotechnology, fundamental biology, human life sciences, microgravity
sciences, Earth science, and advanced technology research. In effect,
a backup crew had been called up for duty and had successfully completed
the flight program. The risk of persevering through difficult times
was now paying off.
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