Simple Hohmann Transfer Orbit Calculator Clicking on the name of a radio button hyperlinks to Bill Arnetts' The Nine Planets web page. The formulas used below can be found at Robert A. Braeunig's Rocket and Space Technology web site.

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Click on a radio button to select a solar system object. This will initialize the values of G, M, and r, below, for the program to calculate orbits around that solar system object. But feel free to change the values for G, M, and r as you see fit...
Sun	Mercury	Venus	Earth	Moon	Mars	Jupiter	Saturn	Uranus	Neptune	Pluto

Grav. Constant (m3kg-1s-2) G

Mass (kg) M

Radius (km) r

Enter an altitude & inclination for both the initial (lowest altitude) and final (highest altitude) circular orbits (around a solar system object selected via the radio buttons). Click "Calculate" to calculate the values shown below using a 1st plane change angle value shown in the First Plane Change(deg) input box. Click "Minimize" to calculate the plane change angles necessary for the smallest value of Total velocity impulse (dvt ).
Initial Orbit:	Final Orbit:
Altitude(km):       Inclination(deg):	Altitude(km): Inclination(deg):
Radius (m) ri = (r+Altinitial)*1000	Radius (m) rf = (r+Altfinal)*1000
Velocity (m/s) vi = (GM/ri)1/2	Velocity (m/s) vf = (GM/rf)1/2
Period (y:d:h:m:s) pi (sec) = (4Pi2ri3/GM)1/2	Period (y:d:h:m:s) pf (sec) = (4Pi2rf3/GM)1/2
Transfer Orbit:
Velocity @ periapsis (m/s) vp = (2GMrf /(ri (rf + ri))1/2	Velocity @ apoapsis (m/s) va = (2GMri /(rf (rf + ri))1/2
Eccentricity et/o = (ri vp 2/GM) - 1	Transfer Time (y:d:h:m:s) pt/o = Pi(((((rf + ri)/2)3)/GM)1/2)
Plane Change Elements:
First Plane Change (deg) O1	First velocity impulse (m/s) dv1 = (vi2+ vp2- 2vi vpcosO1)1/2
Second Plane Change (deg) O2 = |Ot| - O1	Second velocity impulse (m/s) dv2 = (va2+ vf2- 2va vf cosO2)1/2
Total Plane Change |Ot| = Inclinationi - Inclinationf	Total velocity impulse (m/s) dvt = dv1 + dv2

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