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A Day in
Space
Raj
Kaushik
SINCE 1961, more than 450 astronauts have ventured
into space. There are no parks, theatres, shopping malls, or
libraries out there and in the absence of civic amenities it is
difficult to imagine how astronauts spend their time, sometimes up
to a year at a stretch.
Life in space is far different from that
on earth. In space, nights and days are much shorter. Since the
International Space Station revolves around the earth in 90 minutes,
the sun rises every 90 minutes. It’s like 16 days and nights are
crammed into each earthbound day of 24 hours. Peopel are used to
keeping track of time from the shadows of objects under the sun. But
in space there are no trees, so astronauts can’t look out the window
to tell the time. It’s mindboggling how they manage, though. Also,
as the space station revolves around the earth in an elliptical
orbit of 389 to 411 km every 90 minutes, it passes through time
zones fairly quickly.
To solve the problem of keeping track of
time, astronauts and Mission Control record Mission Elapsed Time —
time passed since launch. All events on the space station are
scheduled by MET. Astronauts start their day with a wakeup call from
Mission Control, which sends music to the shuttle crew. Sometimes
the song may be selected by an astronaut’s family. The space station
crew, however, get the old alarm clock treatment.
Sleep and
waking up are special moments in space. There is no gravity so
astronauts are weightless and can sleep while floating around. In
order not to bump into something, they attach themselves to a wall
or sturdy structure in the cabin. After wake-up, they unbuckle
themselves and gently push off the wall to float over to the
lavatory where the toilets are fitted with an air-based suction
system to allow for solid waste to be compacted, dried and stored in
bags.
There is a limited water supply on a station 400 km above
the earth. All the crew members, including lab animals, lose water
when they exhale or sweat. Water reclaimed from solid waste and
humid cabin air is processed and purified. Astronauts use the
recycled water to drink and wash themselves with wet towels.
Usually, each crew member of the space station gets five pairs of
running shorts, five T-shirts, 12 pairs of underwear, eight pairs of
socks, a pair of regular shorts and a pair of trousers.
The
Russian-built Progress unmanned cargo ship carries supplies to the
ISS and collects garbage and unwanted stuff on its return journey.
Progress 14 supplied 1,360 kg of fuel, water, fresh food and
clothing for the Expedition 9 crew on 27 May 2004. There are no
washing machines on the ISS, so dirty clothes are simply discarded
for collection by the cargo ships that bring up supplies.
An
astronaut’s daily food intake consists of three meals and a snack.
Nasa’s food programme is based on the Retort Pouch Technology,
similar to that developed by the military for the Meal Ready to Eat
programme. Food items are stored pantry-style on the space station
so the crew can eat in any order desired. Meal trays are magnetised
so that metal knives, spoons and forks can stick to the tray and not
float around. The trays also contain Velcro strips on the top and
bottom as well. All meal packages are colour-coded and have a Velcro
strip on them. When hungry, an astronaut simply picks up the packet
marked in a colour assigned to him or her.
It’s possible to boil
water and make tea in space, but the problem arises in figuring out
how to drink it. If astronauts try pouring the tea into cups, it
would float around. A situation astronaut Don Pettit got the better
of in 2003 when he used chopsticks to grab small bubbles of tea
coming out of straw and pop them into his mouth. It’s like plucking
soap bubbles in mid-air. Getting down to work involves preparing the
station for routine activities – such as checking for impurities in
the air or plumbing and setting up equipment for scheduled
experiments. For example, Dutch astronaut Andre Kuipers had a list
of 21 experiments to perform, including studying the effect of
weightlessness on blood pressure and heartbeat, as part of the
“Delta” project — the Dutch Expedition for Life science, Technology
and Atmospheric research. Currently, the Expedition 9 crew is
engaged in a Russian experiment called “Profilaktika” that is
designed to measure Commander Gennady Padalka’s cardiovascular
condition while pedalling on a bicycle ergometer. Nasa science
officer Mike Fincke is conducting a fluid dynamics experiment to
measure how spheres of liquid released from syringes behave in
microgravity to form a single sphere.
The next spacewalk, using
Russian Orlan spacesuits, is planned for 3 August. During this
programme, the crew will retrieve earlier outdoor science
experiments and set up new ones. They will also work on the outside
of the Zvezda (the Russian word for star) module’s docking port for
next year’s first flight of the Automated Transfer Vehicle. The
Zvezda module is the primary Russian contribution to the ISS. It is
the main docking port for Russian Progress cargo vehicles. The ATV
is the first vehicle developed by the European Space Agency. It’s
more than a logistics vehicle designed to ferry supplies to the ISS
and its propulsion system will be used by the ISS to raise its orbit
and thus compensate for losing slight altitude over time.
While
busy in activities, the crew members find time to keep in touch with
Mission Control, review scheduled tasks and exercise to keep
muscles, bones and hearts in shape. In their spare time, they e-mail
friends, photograph their home countries and important landmarks on
earth. Sleeping in space can be defined by what spacewalker Greg
Harbaugh had to say: “I believe that weightlessness does affect the
types of dreams. I tried to make a point of remembering what I was
dreaming about last night and I do remember some images of not
walking but floating.”
(The author, a former project
coordinator with the National Council of Science Museums, India, now
works as senior server developer in Toronto.)
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