Lagrangian Points and Nasa's Plan to Explore Space
October 3, 2005
Nasa is relying on its ability to determine the Lagrangian
points between every set of planets, moons, asteroids, etcetera
it intends to explore in order to implement its plan of
successful interplanetary space exploration. Although this at
first may seem to be a vague and mystical concept, foreign to
all but the most overeducated of astrophysicists, in fact it is
really quite simple to understand.
The Lagrangian in physics is merely nothing more than an
alternative set of two equations for Newton's second law; force
equals mass times acceleration. A Lagrangian point between two
bodies exerting competing forces on a body therefore is a point
at which the forces are equal and opposite. According to
Newton's third law, if the net force on a body is zero it will
stay at rest if at rest and if in motion it will stay in motion.
In mathematical terms, visualize a graph of a big bowl. The
Lagrangian point is the point at the very bottom of the bowl.
The energy from the very bottom of the bowl to the top
represents the maximum energy required to kick a body at the
bottom of the bowl out of the bowl and keep it from rolling back
to return to its state of minimum energy. Therefore, in this
case of a mass under the influence of two competing
gravitational forces, the Lagrangian points are the orbits in
which the mass in question will have the greatest ability to
withstand the biggest change in net force upon it that would
disturb it into an unstable orbit.
How this relates to Nasa and its plans for future space travel
is that they have the ability to find the solutions of these
formulas to determine the Lagrangian points lying between
adjacent planetary bodies along the proposed route of space
travel. They are planning to put space stations at these
locations. This will make it possible to create stepping stones
to extend space exploration outwards as far as you want to go.
As it would be unrealistic to expect any spacecraft to be able
to return to earth from deep space in the case of emergency or
the need for repairs, this makes it hypothetically feasible to
conduct space travel without limits in the future.
Sources: 1) NASA Reveals New Plan for the Moon, Mars & Outward
By Leonard David; Senior Space Writer - Space.com