Keplerian Trajectory

What is it?

Thank you,
Christopher Lusardi

wrote:
What is it?

Thank you,
Christopher Lusardi

A fancy phrase for the path followed by some object (say, a
spacecraft) when the only force acting on it is gravity from
one other object (say, the Sun). This path is a conic section;
depending on the initial conditions, it may be a circle, ellipse,
parabola, or hyperbola.

-- Bill Owen

P.S. For you purists out there, yes, I do realize that the
second body must be spherically symmetric. :-)

wrote in news:1144244869.312028.216920
@v46g2000cwv.googlegroups.com:

What is it?

Thank you,
Christopher Lusardi


I'm not sure that Bill's explanation is quite right. Historically, a
Keplerian trajectory would be a segment of a Keplerian orbit as described
by Keplers first law. This means a segment of an ellipse (or circle as a
circle is just an ellipse with zero eccentricity). The other conic sections
mentioned, a parabola or hyperbolia, which are also solutions to Newton's
laws for a two body problem involving gravity would not qualify, as Kepler
himself did not know of such orbits.

Klazmon.

Llanzlan Klazmon wrote:
wrote in news:1144244869.312028.216920
@v46g2000cwv.googlegroups.com:


What is it?

Thank you,
Christopher Lusardi



I'm not sure that Bill's explanation is quite right. Historically, a
Keplerian trajectory would be a segment of a Keplerian orbit as described
by Keplers first law. This means a segment of an ellipse (or circle as a
circle is just an ellipse with zero eccentricity). The other conic sections
mentioned, a parabola or hyperbolia, which are also solutions to Newton's
laws for a two body problem involving gravity would not qualify, as Kepler
himself did not know of such orbits.

Klazmon.

A bit of a nit, you'll admit, but I'm hit.

I accept your correction; thanks.

-- Bill