Chapter 6: Maneuvering in Space Understanding Space Sellers

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Chapter 6 Maneuvering in SpaceUnderstanding
Space (Sellers)
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Supplemental References
1. Liftoff to Space Exploration
http//liftoff.msfc.nasa.gov/toc.aspsOrbital20M
echanics 2. Thomson William T. Introduction
to Space Dynamics John Wiley and Sons
Inc. 1961 3. NSSDC Image Catalog Mission Index
http//nssdc.gsfc.nasa.gov/imgcat/mission_index
.html
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Parking and Other Orbits(Apollo 8)
(NASA GSFC)
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Section 6.1 Hohmann Transfers
Start with
Need specific mechanical

energy and alternate form
For tangential burn
(NASA)
To solve for Vs need energy in each orbit
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Hohmann Transfers
(NASA)
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Hohmann Transfers
(NASA)
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Section 6.2 Plane Changes
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Simple Plane Changes
Assume spacecraft in orbit with inclination i
28.5 and want to change to i 0 Change
orbits orientation not its size Velocity
vectors magnitude stays the same but its
direction changes
Vinitial


Vsimple
28.5

Vfinal
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Combined Plane Changes
Vinitial
Vcombined
Vsimple

Use law of cosines
Vfinal
Vincrease
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Section 6.3 Rendezvous (Using Hohmann Transfer)
Rint
V
Rtarget
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Rendezvous
Coplanar rendezvous
final
Rint
V
lead
Rtarget
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Co-orbital Rendezvous
initial
Phasing Orbit