the explorers journal - The Explorers Club

Earth environments, the longer the duration of
stay, the higher the risk of an underlying medical
disorder causing untoward consequences.
MJM: Isolation and stress could certainly create
psychological problems, especially in someone
with an underlying predisposition or susceptibility.
How do you screen for psychological stability
for long-duration space flight
RW: NASA employs a team of psychiatrists
and psychologists to provide behavioral health
screening, through interview and testing, prior
to selection as an astronaut. NASA behavioral
health personnel support astronauts, and the
flight surgeons taking care of them, throughout
their careers. This behavioral health support intensifies
before, during, and after missions—especially
long-duration missions—with scheduled
opportunities for crew members to interact with
behavioral health specialists.
MJM: Ionizing radiation is more intense in outer
space. How much of a problem will this be and
what measures are being entertained to protect
travelers
RW: Space radiation is different from most terrestrial
sources of ionizing radiation. Space
radiation consists of particles (protons, electrons,
neutrons, and the nuclei of elements)
traveling at light- and near-light-speed. These
particles cause damage at the cellular level as
they pass through tissues. The biological effects
of this unique radiation are not well known,
and research is being pursued to delineate the
short- and long-term risks better. Spacecraft
themselves afford some protection from space
radiation, and spacecraft like the International
Space Station (ISS) contain areas where the
crew members can take shelter in the event of
a space radiation event (such as a solar particle
event). Research for effective shielding materials
and techniques is a priority.
MJM: What are the long-term effects of microgravity
and how will those be addressed or
minimized
RW: The known long-term effects of microgravity
relate mainly to loss of bone-mineral density, cardiovascular
deconditioning, and loss of muscle
strength. These are minimized by aggressive
aerobic and resistive exercise regimens on
orbit, and aggressive rehabilitation upon return.
Evidence concerning long-duration space flight
is still in its early stages, though, and other conditions
and microgravity related health liabilities
might surface.
MJM: How do nutritional requirements for space
travel differ from terrestrial requirements
RW: Nutrition remains one of the great challenges
of human spaceflight. Many astronauts
find that foods taste more bland in space. Some
crewmembers experience weight loss. A great
deal of effort is spent on providing a diet that is
as interesting and varied as possible, while still
fulfilling nutritional requirements.
MJM: What medical issues occur with high-G
forces encountered on launch and reentry
RW: Space Shuttle crew members are exposed
to a maximum G force three times that of gravity.
Despite microgravity deconditioning, crew members
tolerate reentry well. Long-duration crew
members return lying recumbent to minimize the
untoward effects of G forces. The longer the
duration in space, the more difficult G forces are
to tolerate.
MJM: What technologies will be utilized to monitor
astronaut health
RW: On the ISS, we can remotely monitor vital
signs and ECG, perform video telemedicine
activities, perform ultrasonography, and accomplish
limited laboratory work. We are developing
advanced ultrasonic, colorimetric, chromatographic,
video, and other technologies to monitor
astronaut health in real time.
MJM: If an adverse medical event occurs, will
there be instant communication back to earth
to inform and receive instruction on medical
management
RW: Communication delays in low Earth orbit
(LEO) are minimal, though periodic short communications
blackouts can occur. Real time
telemedicine is our primary medical practice
and routinely performed. With exploration
beyond LEO, communications delays ranging
from seconds to 20 minutes will challenge us.
Development of near-autonomous health care
systems to support long-duration flight beyond
LEO is a major goal.
the explorers journal