Table of Contents
Page 1
What Gives the Most Speed to a Spacecraft Flyby? It’s the Gravity Assist.
How Have We Humans Managed to Fling Objects So Far into Space?
Page 2
A gravity assist is free energy for a spacecraft.
The “Shortt” answer: It all depends on point of reference, or “reference frames.”
If the Planet is stationary, energy gained on entry is lost on exit from gravitational force.
There’s a static part of the planet frame, where energy is conserved.
Although energy is conserved in the planet frame, a directional change is caused by the gravity assist.
A gravity assist is free energy for a spacecraft.
The “Shortt” answer: It all depends on point of reference, or “reference frames.”
If the Planet is stationary, energy gained on entry is lost on exit from gravitational force.
There’s a static part of the planet frame, where energy is conserved.
Although energy is conserved in the planet frame, a directional change is caused by the gravity assist.
Page 3
In the Sun frame, where the sun (not the planet) is stationary, what are the variables?
Velocity
Direction
With velocity as a vector, change direction, and you alter speed (a quantity).
Page 4
Here’s how a multi-spacecraft mission used a lunar gravity assist in 2009.
Lunar Crater Observation and Sensing Satellite (LCROSS), Centaur upper stage rocket, and Shepherding Spacecraft positioning
Lunar Reconaissance Orbiter (LRO) positioning
Link to videos about the LCROSS and LRO missions
How to plot an orbit
Page 5
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