DELTA-V BUDGET

'Delta-''v'' budget' (or 'velocity change budget') is a term used in astrodynamics and aerospace industry for velocity change (or delta-''v'') requirements for the various propulsive tasks and orbital maneuvers over phases of the space mission.
Sample delta-''v'' budget will enumerate various classes of manoeuvres, delta-''v'' per manoeuvre, number of manoeuvres required over the time of the mission.
In the absence of an atmosphere and landings where the ground is hit with some speed, the delta-''v'' is the same for changes in orbit the other way around: gaining and losing speed cost an equal effort.

Contents

Launch/landing budget

Stationkeeping budget

Earth-Moon space budget

Interplanetary budget

Delta-vs around the Solar System

Abbreviations used

See also

References

External links

Launch/landing budget

★ Launch to LEO — this not only requires an increase of velocity from 0 to 7.8 km/s, but also typically 1.5–2 km/s for atmospheric drag and gravity drag

★ Re-entry from LEO — no delta-v is required, there is only atmospheric drag

Stationkeeping budget

Maneuver	Average delta-''v'' per year [m/s]	Maximum per year [m/s]
Drag compensation in 400–500 km LEO	<25	<100
Drag compensation in 500–600 km LEO	<  5	<  25
Drag compensation in > 600 km LEO		<   7.5
Station-keeping in geostationary orbit	50 – 55
Station-keeping in L1/L2	30 – 100
Station-keeping in Moon orbit	0 [1] – 400
Attitude control (3-axis)	2 – 6
Spin-up or despin	5 – 10
Stage booster separation	5 – 10
Momentum wheel unloading	2 – 6

Earth-Moon space budget

Delta-v needed to move inside Earth Moon system (speeds lower than escape velocity) in km/s

FromTo	LEO-Ken	LEO-Eq	GEO	EML-1	EML-2	EML-4/5	LLO	Moon	C3
Earth	9.30 - 10.00
Low Earth Orbit (LEO-Ken)		4.24	4.33	3.77	3.43	3.97	4.04	5.93	3.22
Low Earth Orbit (LEO-Eq)	4.24		3.90	3.77	3.43	3.99	4.04	5.93	3.22
Geostationary Orbit (GEO)	2.06	1.63		1.38	1.47	1.71	2.05	3.92	1.30
Lagrangian point 1 (EML-1)	0.77	0.77	1.38		0.14	0.33	0.64	2.52	0.14
Lagrangian point 2 (EML-2)	0.33	0.33	1.47	0.14		0.34	0.64	2.52	0.14
Lagrangian point 4/5 (EML-4/5)	0.84	0.98	1.71	0.33	0.34		0.98	2.58	0.43
Low Lunar orbit (LLO)	1.31	1.31	2.05	0.64	0.65	0.98		1.87	1.40
Moon (Moon)	2.74	2.74	3.92	2.52	2.53	2.58	1.87		2.80
Earth Escape velocity (C3)	0.00	0.00	1.30	0.14	0.14	0.43	1.40	2.80

^[2]
[3]

Interplanetary budget

From	To	delta-v in km/s
Earth Escape velocity (C3)	Mars Transfer Orbit	0.6
Mars Transfer Orbit	Mars Capture Orbit	0.9
Mars Capture Orbit	Deimos Transfer Orbit	0.2
Deimos Transfer Orbit	Deimos surface	0.7
Deimos Transfer Orbit	Phobos Transfer Orbit	0.3
Phobos Transfer Orbit	Phobos surface	0.5
Mars Capture Orbit	Low Mars Orbit	1.4
Low Mars Orbit	Mars surface	4.1
Earth Escape velocity (C3)	Closest NEO Asteroids[4]	0.8 - 2.0

According to Marsden and Ross, "The energy levels of the Sun-Earth L1 and L2 points differ from those of the Earth-Moon system by only 50 m/s (as measured by maneuver velocity)."^[5]

Delta-vs around the Solar System

Abbreviations used

C3	Escape orbit
GEO	Geosynchronous orbit
GTO	Geostationary transfer orbit
L5	Earth-Moon fifth Lagrangian point
LEO-Eq	Low Earth orbit - equatorial
LEO-Ken	Low Earth orbit - "Kennedy inclination orbit"

See also

★ Bi-elliptic transfer

★ Gravity assist

★ Hohmann transfer

★ The Oberth effect

★ Tsiolkovsky rocket equation

References

1. Frozen lunar orbits
2. list of delta-v
3. L2 Halo lunar orbit
4. NEO list
5.
New methods in celestial mechanics and mission design
6. table of cislunar/mars delta-vs
7. cislunar delta-vs

External links

★ Delta V pages at Caltech

★ Javascript Delta V calculator