A double dose of green is heading for the night sky, with two rare comets arcing into view and potentially wowing naked‑eye watchers under dark, moonless conditions.

The duo reaches peak brightness Monday, Oct. 20, and Tuesday, 21, with viewing continuing through late October. Both are best seen from the Northern Hemisphere.

Comet Lemmon (C/2025 A6) should be the easier catch. Look about 90 minutes after sunset or before dawn toward the northwestern sky, near the Big Dipper.

Expect a faint, fuzzy, blue‑green glow rather than a sharp point of light. Binoculars will help it stand out as a small, greenish ball. Lemmon follows a 1,350‑year orbit and was discovered in January 2025.

Comet SWAN (C/2025 R2) is dimmer but nearby in cosmic terms. It makes its closest pass on Monday, and will lik

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