prograde/retrograde
Mar. 7th, 2016 07:32 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
prettygoodwordretrograde (RE-truh-grayd) - adj., moving backwards, as in (astro.) moving in an orbit that is opposite a reference orbit or rotation, such as the Earth's; proceeding from last to first; contrary, conterproductive.
prograde (PROH-grayd) - adj., moving in an orbit that is the same direction as a reference orbit or rotation.
If a satellite moved east to west, opposite the Earth's rotation of west to east, it would be in a retrograde orbit. It's easier, because of angular momentum, to launch one into a prograde orbit. Retrograde is older, from Latin retrōgradus, going back, from retrō- back/backwards + gradī, to step/go. Prograde was coined in 1967 on its model.
---L.
prograde (PROH-grayd) - adj., moving in an orbit that is the same direction as a reference orbit or rotation.
If a satellite moved east to west, opposite the Earth's rotation of west to east, it would be in a retrograde orbit. It's easier, because of angular momentum, to launch one into a prograde orbit. Retrograde is older, from Latin retrōgradus, going back, from retrō- back/backwards + gradī, to step/go. Prograde was coined in 1967 on its model.
---L.
