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First-quarter light opens Apenninus and the Straight Wall on 19 September

The annual Moon-watch night is 19 September 2026, first-quarter phase. Space.com aims readers at Montes Apenninus and Rupes Recta on the half-lit disk near Sagittarius.

Science··Evening
A first-quarter Moon with rugged terminator relief hangs over a twilight hillside while an anonymous observer uses a small amateur telescope.

19 September, first quarter, near Sagittarius

Wood's Space.com guide posted 19 September 2026 at 14:00 UTC and marks that evening's first-quarter disk as the annual lunar observing night. The disk glows on the southern horizon near Sagittarius. The date is the annual NASA observing night. The phase is first quarter.[1]

Apenninus 600 kilometres; Rupes Recta the Straight Wall

On the listed map, Montes Apenninus sits roughly 20 degrees north of the Moon's equator along Imbrium's southeast shore, 600 kilometres across and as high as 5 kilometres. Rupes Recta, called the Straight Wall, lies in southeastern Mare Nubium. Space.com also names Eratosthenes, Tranquility Base and Mare Crisium. Those sizes are in the Space.com copy.[1]

A sky guide, not a new flight

The copy is a target list for NASA's yearly look-up night. It is not a new mission result, a new landing, or a new instrument paper. Readers looking for a flight announcement will not find one here. The card reports the targets as listed for that first-quarter evening.[1]

References

  1. News sourceSpace.comFirst-quarter Moon opens Apenninus and Rupes Recta on 19 Sep↩1↩2↩3