ISO week 51 2025
This week is currently in preparation and will be published as part of the Star Almanack.
Week begins: Monday, December 15, 2025
Notation:
Calendar
| Date | Zodiac day | Events |
|---|---|---|
| Mon, Dec 15, 2025 | ♐ 24 | Polaris (α UMi) —  V 2 — Arctic Autumn |
| Tue, Dec 16, 2025 | ♐ 25 | |
| Wed, Dec 17, 2025 | ♐ 26 | Aries center — Constellation — V 3.1 — Tropical AutumnM34, open cluster in Perseus —  V 5.5 — Northern AutumnM77, spiral galaxy in Cetus —  V 8.9 — Tropical AutumnNGC 1023, galaxy in Perseus — V 9.6 — Finest NGC — Northern Autumn |
| Thu, Dec 18, 2025 | ♐ 27 | ☉ Galactic Center conjunction — 21:24:46 UTC Fornax center — Constellation — V 4.5 — Southern Autumn |
| Fri, Dec 19, 2025 | ♐ 28 | β For — V 4 — Southern AutumnHead of Cetus center — Asterism — V 2.5 — Tropical AutumnC67, NGC 1097, barred spiral galaxy in Fornax — V 9.2 — Southern Autumn |
| Sat, Dec 20, 2025 | ♐ 29 | 🌑 New Moon — 01:43:21 UTC |
| Sun, Dec 21, 2025 | ♑ 1 | ♑ Sun enters Capricorn · Winter solstice · Yule — 15:03:05 UTC β Hor — V 5 — Southern Winter |
Weekly Solar-System Ephemeris
Snapshot: December 15, 2025 · 00:00 UTC
Notation:
Naked Eye
| ☉︎ Sun | ☽︎ Moon | ☿︎ Mercury | ♀︎ Venus | ♂︎ Mars | ♃︎ Jupiter | ♄︎ Saturn |
|---|---|---|---|---|---|---|
| ♐︎ 23°15′ β −0°00′ | ♎︎ 28°06′ β −3°34′ | ♐︎ 3°56′ β +1°32′ | ♐︎ 17°49′ β +0°10′ | ♐︎ 29°46′ β −0°46′ | ♋︎ 23°22′ β +0°12′ | ♓︎ 25°25′ β −2°19′ |
| Observing | ||||||
| ☉ | | ☉ | ☉ | ☉ | | |
Extended targets:
| ⚳︎ Ceres | ♅︎ Uranus | ♆︎ Neptune | ♇︎ Pluto |
|---|---|---|---|
| ♈︎ 4°06′ β −10°07′ | ♉︎ 28°30′ β −0°12′ | ♓︎ 29°23′ β −1°21′ | ♒︎ 2°14′ β −3°46′ |
| Observing | |||
| | | |
β = ecliptic latitude (+ north, − south). Observing combines visual magnitude with solar elongation. Two telescope glyphs = substantial telescope. ☉ = Near Sun — not currently observable.
Notation:
Planet Finder
Sky Notes
Naked eye
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Binoculars
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Telescope
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.