Simple orbital calculations — single orbit + Hohmann transfer

Orbital Calcs

MODE

Central body

Gravitational parameter
Used if you enter altitudes

Craft

Used for propellant estimate
Rocket equation (assumes vacuum)
For transfer arrival time

Inputs

Single orbit (circular)

If altitudes: A = altitude. If radii: A = distance from center.
If set, shows speed/period at B too (still circular at each)

Transfer (Hohmann, circular → circular)

Results

Δv total
Prop required
Time / Period
Arrival / Notes
Ready.

Orbit sketch

Not to scale (but it helps sanity-check direction + relative sizes).