Molniya — Lesson 7

A Molniya orbit is a highly inclined and highly elliptical semi-synchronous orbit (generally around e = 0.7). Due to its high eccentricity, it has a large apogee altitude which results in a very slow velocity at apogee. Molniya orbits have an easily identifiable ground track. Since the orbit drastically slows down at apogee, the Earth’s rotation temporarily outruns the satellite. This causes the satellite to appear to loop back on itself in its ground track.

Molniya orbits were developed by Russia because using geostationary satellites for communications posed severe problems since so much of the country's land mass is near or north of 70 degrees in latitude. If apogee occurs over Russia, the satellite “hangs” over Russia for a long period.

Common Uses and Benefits: Russian launches don’t need to waste fuel to lower the satellite's inclination; satellite “hangs” over Russia and North America; Russian communications.