NASA astronaut
John Phillips briefed a congressional panel on the merits of the International
Space Station (ISS) Tuesday while circling the Earth aboard the orbital
research facility.
Phillips, science
officer and flight engineer for ISS Expedition 11, is NASA's first astronaut to
testify before a congressional committee from space. He joined two other space
station veterans, Expedition 5
flight engineer Peggy Whitson and Expedition 9
flight engineer Michael Fincke, who spoke to committee members from the ground.
"Onboard
the International Space Station, we are the experiment," Phillips said via
satellite link from inside the station's U.S.-built Destiny laboratory. "We are
trying to learn as much about human spaceflight as we can."
Phillips
and his fellow astronauts spoke before members of the House Science
Subcommittee on Space and Aeronautics. Of primary interest to committee members
were the challenges faced by ISS astronauts, the space outpost's scientific
payoffs and its role in the future human exploration once NASA's shuttle
program retires in 2010.
"We can't
be flying at $1 billion a flight and expect to keep flying a space shuttle,"
said Congressman and subcommittee member Dana Rohrabacher (R-California). "The
costs have to be lowered."
Phillips told
subcommittee members that the space station is about only half-built and awaits
delivery of additional support trusses, pressurized nodes, modules and
laboratories, each anticipating its turn to launch aboard a NASA space shuttle.
Two new laboratories - Japan's Kibo module and Europe's Columbus module - still
remain Earthbound, but could boost the number of ISS astronauts up to crews of
six when finally delivered to the station, he added.
"Our
experimental time is somewhat limited now," Phillips said. "[But] when there are
six people aboard, there will be a lot more experimentation."
Previously,
ISS crews and flight controllers depended on NASA space shuttles to deliver new
station components and bulky replacement parts that are too large to ride
aboard Russian Progress cargo vehicles. But NASA's shuttle fleet has been
grounded since the 2003 loss of the space shuttle Columbia and its astronaut
crew during reentry.
"One of the
things brought home by the Columbia accident is that we need to stamp out
complacency anywhere it exists," Phillips told the subcommittee. "[Spaceflight]
is not like getting on an airliner, we strap ourselves on a rocket and there
are some risks."
Dangers to
astronaut health are among the spaceflight risks astronauts and flight
controllers hope to better understand via ISS research, Fincke said.
"Aboard the
space station, I lost a fair amount of bone mass, about six percent," Fincke said,
adding that he managed to regain that lost bone mass after returning to Earth
from his 187-day mission. "That's accelerated osteoporosis, and by
understanding how we lose [bone mass], how we limit it and how we can get it
back, there are some direct applications to those of us on the ground."
Whitson
told subcommittee members that the current resupply needs of the ISS, which requires
the steady arrival of unmanned Progress spacecraft every six months to support
the outpost's two-person crews, are too great for a future moon base or Mars
station.
"We need to
build hardware at a much higher level of maintenance," Whitson said.
advertisement
