Assignment 3- Investigate the essential factors involved
in space flight.
What is spaceflight? Spaceflight is the administration of astronauts
and astronautics to fly into outer space with a spacecraft. Spaceflight
could be done with humans on board or without any humans on-
board. There are a number of types of spaceflights these include,
flyby spacecraft, lander spacecraft, orbiter spacecraft,
communications and navigation spacecraft, rover spacecraft,
penetrator spacecraft and observatory spacecraft. Most of the
spaceflights that takes place are uncrewed due to the dangers the
outer space atmosphere can cause to the human body. So, the space
crafts that are usually sent to outer space are monitored and
controlled from science organisations on
earth such as NASA and other Space
Organisations.
Figure 1 to the right shows a picture
of a spacecraft departing earth:
C.P.5: For a successful spaceflight whether unmanned or
manned there are a couple of precautions and factors that need to
be examined and taken into consideration for instance construction
materials for the spacecraft, fuels, escape velocity, hazards to both
humans (if there are humans in the spacecraft) and the spacecraft,
costs, training of astronauts, communications and stages of a
spacecraft.
,Spacecraft materials: Spaceships tend to use materials such as metals
that are light weight such as aluminium of high grade and aluminium
composite materials. Aluminium is sturdy. Titanium can also be used
to build a spacecraft because it helps strengthen the body of the
craft. To make the craft airtight aluminium and titanium is mixed
together with Teflon coating to prevent the metals cold welding
against each other in the vacuum of the space. The space shuttle also
has special thermal tiles that protect and help the re-entry of heat.
Plastic is used in the development of a spacecraft to reduce and
block heat radiation. Spacecrafts tend to be coated with ceramic to
withstand high temperatures and helps the craft weigh less than
metal components.
Figure 2 above shows a spacecraft made out of aluminium
metal.
,Fuels: There are two types of rocket fuels Morden Spacecrafts use
and these are either in the solid state or liquid state. The liquid fuel
separates the fuel and the oxidisers and the two het combined in
combustion chamber where they get burned together and sent to
the base of the spacecraft. Spacecraft grade petroleum is called RP-1
and has a high refined kerosene mixed together with the liquidised
oxygen.
Figure 3 above shows a picture of the chamber where the
spacecraft’s fuels goes into.
Solid Fuels are fuels which the oxidiser and the fuel are already
combined. Aluminium powder is the substance usually used as the
fuel and ammonium perchlorate as the oxidiser. Iron powder is
added to the equation for it to act as a catalyst to speed up the
process of making the fuel. Solid fuels are generally used in the
launch phase of a spacecraft but when the speed need to be
increased the liquid fuel is added for the spacecraft to reach its
maximum in a few seconds.
,Escape Velocity: Escape Velocity is the pace that an entity needs to
travel to escape the gravitational body or the moon. A spacecraft
leaving the surface of the earth needs to be travelling at about
7miles/ second or twenty five thousand miles per second to leave
without falling back to the surface or the orbit. Escape velocity
entirely depends on the mass of the planet so a spacecraft leaving
the surface of the moon would go slower than one which is leaving
earth because the moon has reduced gravity than earth. The escape
velocity of the earth from its surface is roughly about
11.2km/second. The escape velocity of the moon is roughly 2.4km
per second.
Electric Supply in space: A spacecraft gets its energy from batteries,
unstable atoms or the natural source of energy which is the sun.
When in the process of planning a trip to outer space, engineers
have to consider where the spacecraft is going to travel to be able to
determine which types of energy it is going to use when travelling. If
the craft is planned to go to Venus or Mercury it would be best if the
spacecraft gets its energy from the sun through solar cells that would
be attached to the body of the craft.
Importance of oxygen tank: The oxygen levels of astronauts who
leave earth decreases as they go further out of the earth’s
atmosphere. As they are sealed inside a confined space for so long,
they inhale the oxygen in the air and gets absorbed by the blood and
used by the body, so they would need more oxygen for them to keep
alive and remove the carbon dioxide from the cabins atmosphere.
Hazards in space: The main hazards of spaceflight are radiation,
distance from earth, isolation, gravity fields, hostile environment
space debris, freezing temperatures, Burning heat, G forces and
microgravity just to mention a few.
Radiation: Radiation is the spreading of energy through matter or
space in form of particles or waves. In space there are about three
,types of radiations astronauts are exposed to, these are solar
particles which are released by the sun during solar particle events,
radiation trapped by the earth’s magnetic field, galactic cosmic rays
(that originate outside the solar system GCR). Radiation in space is
powerful to the extent that it can break a humans DNA molecules
which can easily kill a cell. There will be a higher chance of the
development of cancer in the human body when they are in space.
Some of the health problems can skip the astronaut who went to the
outer space but appear in descendants down the bloodline which
will be passed on by the mutated genes. Sterility can develop in the
astronaut’s body overtime or even immediately while in outer space.
Hazards of space can emerge to be acute or long term effects.
Distance from earth: Distance from earth to outer space is
approximately about 62miles (100 kilometres). The distance from
earth to outer space makes astronauts’ bodies weak and unable to
properly deal with the pressure against them. Astronauts will be
away from Earth for a long time for instance, Mars is 140million
miles from planet earth so astronauts would have to leave earth for
about four years roughly.
Isolation: Isolation in space leads to a number of problems for
astronauts. These problems are fatigue, sleep disorders, altered
stress, and hormone levels, immune modulatory changes which is a
substance that suppresses the immune system and helps the body
fight antibodies like cancer, infections and other diseases
neurocognitive changes. Neurocognitive change is the reduction of
psychological function in some areas of the body such as the brain.
Isolation can also cause problems where an individual can easily lose
their confidence in communicating with other people in everyday
life.
Gravity Fields: Gravity fields in space are low and no longer fighting
the pull of gravity therefore weightlessness can cause several key
systems in the human body to relax. Gravity fields affect balance,
, space motion sickness and spatial orientation which is the ability to
identify the position or direction of objects or points in space.
Hostile Closed Environment: Living in a spacecraft for about three-
five years can easily make the astronauts feel/develop being
claustrophobic.
Space Debris: Small space debris can damage important components
like solar panels, Spacecrafts and satellites. Debris could hurt an
astronaut physically by burning or cutting them or their space gear
depending with how serious the damage of the debris can get
Freezing Temperature: Freezing temperatures can easily make one
develop hypothermia or if not treated with immediate effect it could
lead to death.
Burning Temperature: Burning temperature can easily lead to the
high body temperature of an astronaut, burning of the skin, blisters,
redness on the skin and even cancer because of the sun radiations.
Microgravity: Subjection to zero gravity often leads to perplexity and
decreased neuromuscular coordination. Shortly after landing back on
planet Erath astronauts can have difficulty in walking, turning, being
able to stabilize their gaze and standing up.
G- Forces: G forces are the result of acceleration of spacecraft.
Astronauts can feel the g force at any speed as long as the craft is
speeding up. However if the spacecraft was not moving at all the
astronauts would not experience any force at all.
Hazards to the Spacecraft: The spacecraft would return to earth but
would have damages on it. Certain parts of it would have been
peeled off or scratched off by hard objects that could damage the
surface of the spacecraft. Other small parts of the spacecraft could
start fading away like the engine and other parts of the spacecraft
due to the atmosphere surrounding it.
