What is “Beyond the Blue”?
Stars have fascinated the people since
ancient times, but wasn’t until the 20th century that exploring
space became possible. In recent decades we have sent astronauts to the moon,
robotic space crafts to the outer reaches of the solar system and used the
telescopes to peer across the vastness of the Universe. Exploring beyond the
blue sky became a reality to the mankind.
Observing the skies
For centuries, astronomers have observed
the heavens with their eyes alone or used simple telescopes that magnify the
view. But the visible light we see is just one part of a much bigger spectrum
of electromagnetic rays that reaches the earth from space. Stars and other
objects also emit invisible radio waves, x-rays, infrared, and microwave rays.
Modern telescopes can see all of these, and each type of radiation reveals
something different.
Capturing
the light
Telescopes come in many different styles
and designs, but basically all do the same thing: collect electromagnetic
radiation from space and focus it to create an image. Earth’s atmosphere can
block or blur the image, so some telescopes are located on high mountain tops
or even launched into space. Some known telescopes among them are;
Radio telescopes : Huge, curved dishes are used to focus radio waves given out by sources such as galaxies, pulsars and black holes
|
Microwave telescopes : Microwaves are short radio waves. By capturing these rays, telescopes can see ancient radiation from the Big bang.
|
Optical telescopes : Using large lenses or mirrors, optical telescopes gather faint visible light and can see much further than the human eye.
|
Infrared telescopes : These instruments, some of them are sent into space, detect the heat from the objects such as clouds of gas and dust.
|
Mapping the stars
Because Earth is
surrounded by space, when we look at the night sky it seems as though all the
stars are pinned to the inside of a
gaint sphere. Astronomers call this a celestial sphere and use it to map the
positions of stars and planets. Vertical and horizontal lines are used to
divide the celestial sphere into a grid, just like the grid of latitude and
logitude lines used to map the Earth’s surface. Some among them are,
1. Celestial north pole- This is the point directly above
the north pole.
2.
Celestial south pole- This is the point directly above
the south pole.
3.
Declination line- These split the sky into north south
segments.
4.
Right ascension lines- These divide the sky into east
west segments.
5.
Celestial equator- This imaginary line over the equator
divides the sky into
north south hemispheres.
north south hemispheres.
Exploring the planets
The planets are too far for
manned missions, so robotic spacecrafts are sent instead. The first visit
to another planet was made by ‘Mariner 2’, a US craft that flew past Venus in
1962. Since then, and despite number of failures, hundreds of spacecrafts have
visited the solar system’s planets, moons, asteroids and comets. Most
spacecrafts either fly past or orbit their target, but some also release
landers that touch down on the surface.
An ORBITER is the one which
flies around a planet repeatedly giving it plenty of time to study its target.
Orbiters have visited the moon and all the planet except Uranus and Neptune.
A PENETRATOR
is one which is designed to hit its target at high speed and bury
itself. In 2005, satellite ‘Deep impact’ penetrated the surface of a comet.
A ROVER is a robotic lander
with wheels that can drive about. Rovers sent to mars have studied its rocks
for signs of ancient life.
12 years and 43 days- the
time it took the spacecraft ‘Voyager 2’ to reach Neptune from Earth.
|
- 1 Ultraviolet sensor
- 2 Generator
- 3 Magnetometer
- 4 Infrared sensor
- 5 Communication dish
- 6 Asteroid detector
Launch vehicles
Space
is only 100 km above earth’s surface and takes less than 10 minutes to reach in
a rocket. Although the journey is short, it takes tremendous power to escape
the pull of earth’s gravity. Launch vehicles are built to make the journey only
one time, and most of their weight is fuel
World’s
largest rockets
Saturn V, which sent astronauts to the moon
was the largest rocket ever built. Some large rockets are..
Delta heavy-72m |
Long march 2F-62m |
Arine 4-59m |
Launch sites
Many countries have space flight launch
sites. Sites closer to the equator can launch heavier cargo, because rockets
are given a boost by the speed of Earth’s spin.
Major launch sites.
Living
in space
Astronauts must adapt to a zero gravity
environment when living in space. Although floating weightlessly can be fun, it
can also cause medical problems. Space stations are cramped places with few
luxuries. Astronauts eat ready-made food that are either freeze-dried or served
in pouches. All waters are recycled, including water vapour from human breath.
Astronauts clean themselves with special shampoos and soaps that don’t need
water, and they use space toilets that suck away waste rather than flushing with
water.
Effects
on the body
When the human body spend a long time in space,
it changes. Without gravity pulling the spine, the body gets about 5cm taller. Body
fluids that flow downwards on earth build up in head. This gives astronauts
swollen faces and blocked noses, making food seem tasteless. When astronauts
come back to the earth, the return of gravity can make them feel extremely weak
- Brain and balance: Without gravity, the inner ear’s balance system no longer works which can make astronauts sick.
- Muscles: Movement is easy when you are weightless, and muscles waste away if not used. Workout in on-board gym help to stop this happening.
- Bones: Bones weaken and become less dense. Regular excersice is essential to keep them strong.
Conclusion:
Space exploration has given us new
technologies and now inspires new ideas for the program. Even though it has
many good effects, the exploration contributes to global warming, there are
ozone depleting substances and man-made debris in the earth orbit which must be
controlled. Explorers and
scientists are trying to sort out the problems of pollution and effects of harm
nowadays.
SUBMITTED BY:
SHAYANA
SUJITH
LALAN
THILAKA
1st M.Sc {1st Semester}
REFERENCE:
Internet
Journal