Shall NASA be Able to Re-position an Asteroid

PRLog - Dec. 30, 2012 - DELHI, India -- 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.

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