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Shall NASA be Able to Re-position an Asteroid

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					Shall NASA be Able to Re-position an
Asteroid?
Summary: NASA has recently announced its intention to capture an asteroid and
re-position it close to moon, to be used as space station. However several
conditions need to be taken into consideration to accomplish the task and hence it
may really not be possible for NASA to meet its stated objectives.

American space agency has recently announced its intention to re-position an
asteroid close to moon in an orbit and use it as a space station. NASA has claimed
that it has all the technology to accomplish the task. It is expected to serve as a
proving ground for hardware and crews en route to larger objects deeper into
space.

In April, the Keck Institute for Space Studies at the California Institute of
Technology reported its conclusion that a 5, 00,000-kg (1.1-million-lb.) near-Earth
asteroid (NEA) could be discovered, tracked, captured and delivered to cislunar
space by 2025 at a cost of about $2.65 billion.

Keck concluded that placing a 500-ton asteroid in high lunar orbit could provide a
unique, meaningful and affordable destination for astronaut crews in the next
decade. This disruptive capability would have a positive impact on a wide range of
space exploration interests, which includes developing technology to deflect an
asteroid on its way to a disastrous collision with Earth’s atmosphere.

Astronomers on the Keck team estimated that a “low-cost, ground based
observation campaign” could identify five or so candidate targets per year in the
desired 7-meter-dia. Range.

A spacecraft generating power with large circular “Mickey Mouse” solar arrays
would use Xenon-based 10-kw Hall thrusters to spiral out to the desired NEA –
firing four at a time, each with a specific impulse of 3,000 sec. As it approaches
the target, it would use on board instruments to characterize its shape and
rotation, and apply algorithms developed by the Defense Advanced Research
Agency to match its spin. Then it would essentially lasso the NEA with a 15-meter
dia. “capture bag” that would be clinched tight over the spinning space rock, once
the spacecraft and asteroid are tightly secured together, the spacecraft would
then de-tumble the combination. The Keck study experts calculate that it would
take 300 kg of propellant to stabilize the asteroid.

After that, the spacecraft could use its solar-electric propulsion to work its way
into a high lunar orbit or even one of the Earth- Moon Lagrangian points that
NASA is studying as way stations that avoid fuel-consuming gravity wells en route
to destinations beyond low Earth orbit.

It is well known that all celestial bodies maintain precise elliptical orbits. A circular
orbit can easily be understood on the basis of balance of gravitational force of
attraction and centrifugal force but elliptical orbits that are precisely maintained
over an immense period of time can’t be thus explained. No doubt, Kepler’s laws
of planetary motion have sufficient room for elliptical orbits but they only define
the conditions that are met and not the mechanisms utilized to meet the
conditions. It is implicit even in ‘Kepler’s equal area law’ that elliptical orbit
requires mathematically-precise maintenance. There is really no room for a
celestial body to wander about its elliptical path. Elliptical orbits, for example,
involve precise movement of Earth towards Sun during part of its journey and
precise movement of Earth away from Sun during another part of its journey. Not
only this, it also involves precise conservation of total energy of a celestial body all
the time. Therefore elliptical movement of celestial bodies is quite unlike the
pendulum movement which involves total inter-conversion of kinetic energy into
potential energy and vice versa. Elliptical orbits of celestial bodies involve
mathematically precise partial inter-conversion of kinetic energy and potential
energy. We just don’t know as to how celestial bodies conserve their energy,
maintain precise elliptical paths, precisely regulate inter-conversion of kinetic
energy into potential energy and vice versa; and precisely move towards or away
from their Sun.

Re-0positioning an asteroid into a new orbit demands precise understanding of
these considerations so that appropriate technology can be developed to meet
above stated considerations. However, since astronomers/physicists have never
posed these questions to themselves, therefore there can’t be any solutions to
these questions either.

Hence, NASA may have the technology to be able to discover, track, capture and
deliver an asteroid to cislunar space but it is unlikely to have technology to keep it
in cislunar space along a precise mathematically predictable elliptical orbit. This
must be true and correct at the present level of understanding and technology
development.

Therefore NASA with all its resources is unlikely to be able to re-position an
asteroid into a new home. Yet this technology may be useful to deflect an
asteroid on its way to a disastrous collision with Earth’s atmosphere.

Author: Dr Mahesh C. Jain is a practicing medical doctor has written the book
“Encounter of Science with Philosophy – A synthetic view”. The book begins with
first chapter devoted to scientifically valid concept of God and then explains
cosmic phenomena right from origin of nature and universe up to origin of life
and evolution of man. The book includes several chapters devoted to auxiliary
concepts and social sciences as corollaries to the concept of God. This is the only
book that deals with origin of nature and universe from null (Zero or nothing).
This article is in line with author’s understanding of nature.

Visit: http//www.sciencengod.com

     http://curatio.in

				
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Description: Summary: NASA has recently announced its intention to capture an asteroid and re-position it close to moon, to be used as space station. However several conditions need to be taken into consideration to accomplish the task and hence it may really not be possible for NASA to meet its stated objectives.