Extra exam question E3A03
Subelement E3, RADIO WAVE PROPAGATION· Group E3A
When scheduling EME contacts, which of these conditions will generally result in the least path loss?
- A.When the Moon is at perigee (correct answer)
- B.When the Moon is full
- C.When the Moon is at apogee
- D.When the MUF is above 30 MHz
WhyEME path loss is least when the moon is at perigee, its closest point to Earth. EME path loss is dominated by the enormous round-trip distance to the moon and back, so scheduling a contact for when the moon is at perigee, its closest point to Earth, shortens that path and reduces the loss more than any other listed factor, answer A. Whether the moon is full has no bearing on radio path loss, apogee is the moon's farthest point and would increase loss instead, and MUF above 30 MHz describes an unrelated HF ionospheric condition.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
Related questions
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- E3A02What characterizes libration fading of an EME signal?
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- E3A06What should be done to continue a long-distance contact when the MUF for that path decreases due to darkness?