Hohmann Transfer Orbit Diagram
The diagram shows the initial circular orbit in blue, the elliptical transfer orbit in green, and
the final circular orbit in red. Each phase is labeled: initial orbit, first burn, elliptical transfer
orbit, second burn, and final orbit. Arrows indicate the direction of travel.
Hohmann Transfer Orbit
A Hohmann transfer orbit is a method used to move a spacecraft from one circular orbit to
another using two engine impulses. It is the most energy-efficient way to transfer between
two orbits when the orbits are coplanar.
Steps:
1. Initial Orbit: The spacecraft starts in a lower circular orbit.
2. First Burn: An engine burn at the perigee increases the spacecraft's velocity, moving it into
an elliptical transfer orbit.
3. Elliptical Transfer Orbit: The spacecraft coasts along this orbit towards the apogee.
4. Second Burn: At the apogee of the transfer orbit, another engine burn increases the
spacecraft's velocity to circularize the orbit at the higher altitude.
5. Final Orbit: The spacecraft is now in a higher circular orbit.
Bi-Elliptic Transfer Orbit
A colorful diagram showing the bi-elliptic transfer orbit. The diagram should include the
initial circular orbit, two elliptical transfer orbits, and the final circular orbit. Label the
phases: initial orbit, first burn, first elliptical orbit, second burn, second elliptical orbit, third
burn, and final orbit. Use distinct colors and arrows to indicate the direction of trave
A bi-elliptic transfer involves two elliptical orbits and three burns. It is used when the target
orbit is much higher than the initial orbit and can sometimes be more efficient than a
Hohmann transfer for large changes in orbital radius.
Steps:
1. Initial Orbit: Start in a lower circular orbit.
2. First Burn: Perform a burn to enter the first elliptical transfer orbit, with an apogee much
higher than the target orbit.
3. Coasting Phase 1: Coast to the apogee of the first elliptical orbit.
4. Second Burn: Perform a burn at the apogee to enter the second elliptical transfer orbit.
5. Coasting Phase 2: Coast to the intersection with the target orbit.
6. Third Burn: Perform a burn to circularize the orbit at the target altitude.
Geostationary Transfer Orbit (GTO)
A geostationary transfer orbit is used to transfer a satellite from a low Earth orbit (LEO) to a
geostationary orbit (GEO). It typically uses a Hohmann transfer orbit.
Steps:
1. Launch into LEO: Place the spacecraft in a low Earth orbit.
2. First Burn to GTO: Perform a burn to enter an elliptical transfer orbit with an apogee at the
geostationary altitude.
3. Coasting Phase: Coast along the transfer orbit to the apogee.
4. Second Burn: Perform a burn to circularize the orbit at the geostationary altitude.
Lunar Transfer Orbit (LTO)
A lunar transfer orbit is used to transfer a spacecraft from low Earth orbit to a lunar orbit.
The diagram shows three stages: the initial low Earth orbit in blue, the elliptical transfer
orbit in green, and the final lunar orbit in red. The arrows indicate the direction of travel, and
the points where burns occur to change orbits are labeled. The diagram includes the Earth and
the Moon.
Steps:
1. Launch into LEO: Place the spacecraft in a low Earth orbit.
2. Trans-Lunar Injection (TLI): Perform a burn to enter an elliptical transfer orbit that intersects
the Moon's orbit.
3. Coasting Phase: Coast along the transfer orbit to the Moon.
4. Lunar Orbit Insertion (LOI): Perform a burn near the Moon to enter a lunar orbit.
