Phrase guide
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.
No pronunciation record was provided for this word.
noun
The altitude of periapsis at which atmospheric drag will prevent an object from successfully orbiting.
Definition source: English Wiktionary via Wiktextract
Topics: aerospace, business, engineering, natural-sciences, physical-sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
Alternative form of McDowell line.
Definition source: English Wiktionary via Wiktextract
Usage: alt-of, alternative
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
Proposed by astrophysicist Jonathan C. McDowell in 2018; when analyzing orbiting satellites to determine the perigee altitude at which one can successfully orbit twice or more on a highly elliptical orbit.
