ISO 2025-W52
Week begins: Monday, December 22, 2025
Calendar
| Date | Zodiac day | Events |
|---|---|---|
| Mon, Dec 22, 2025 | ♑ 2 | Menkar (α Cet) —  3 2.5 — Tropical Winter |
| Tue, Dec 23, 2025 | ♑ 3 | Algol (β Per) / Algol (β Persei) — Var 2 2.1 2.1–3.4 — Northern Winter |
| Wed, Dec 24, 2025 | ♑ 4 | Finest NGC 21 / NGC 1232 · Arp 41 —  11 10.6 — Tropical WinterFinest NGC 10 / IC 289 · PN G138.8+02.8 — 12 12.0 — Northern WinterDalim (α For) —  4 3.8 — Southern WinterC87 / NGC 1261 — 8 8.4 — Southern Winter |
| Thu, Dec 25, 2025 | ♑ 5 | |
| Fri, Dec 26, 2025 | ♑ 6 | C24 / NGC 1275 · Perseus A — 12 11.6 — Northern Winter |
| Sat, Dec 27, 2025 | ♑ 7 | 🌓 First Quarter — 19:09:51 UTC Mirfak (α Per) — 2 1.8 — Northern Winter — in the Milky Way |
| Sun, Dec 28, 2025 | ♑ 8 |
Weekly Solar-System Ephemeris
Snapshot: Week begins December 22, 2025, 00:00 UTC.
(-90° to +90°; defaults +45°, 21:00 LAT)
| Body | ☉︎ | ☽︎ | ☿︎ | ♀︎ | ♂︎ | ♃︎ | ♄︎ |
|---|---|---|---|---|---|---|---|
| Ecliptic | ♑︎ 0°23′ β −0°00′ | ♑︎ 21°51′ β −3°50′ | ♐︎ 13°44′ β +0°38′ | ♐︎ 26°37′ β −0°07′ | ♑︎ 5°04′ β −0°49′ | ♋︎ 22°36′ β +0°13′ | ♓︎ 25°40′ β −2°18′ |
| Observing |  | -6.1 | ☉︎ | ☉︎ | ☉︎ | -2.6 | 1.0 |
| Rise | 07:37 | 09:25 | 06:19 | 07:23 | 08:03 | 17:58 | 11:59 |
| Set | 16:23 | 17:46 | 15:18 | 16:04 | 16:38 | 09:14 | 23:34 |
Extended targets:
| Body | ⚳︎ | ♅︎ | ♆︎ | ♇︎ |
|---|---|---|---|---|
| Ecliptic | ♈︎ 5°10′ β −9°35′ | ♉︎ 28°15′ β −0°12′ | ♓︎ 29°25′ β −1°20′ | ♒︎ 2°26′ β −3°46′ |
| Observing | 8.8 | 5.6 | 7.8 | 14.6 |
| Rise | 12:57 | 14:16 | 12:02 | 09:59 |
| Set | 00:08 | 05:09 | 23:55 | 18:42 |
β = ecliptic latitude (+ north, − south).
Rise and set are Local Apparent Time for the selected latitude.
Naked-eye observing uses the Sun’s altitude at the selected Monday observer time: Daylight (Sun ≥ −0.833°), Civil twilight (−0.833° to −6°), Nautical twilight (−6° to −12°), Astronomical twilight (−12° to −18°), and Night (below −18°).
Solar Glare identifies a body too close to the Sun when the sky-state rule does not already supersede its naked-eye classification.
The Sun’s observing status uses this same five-state sky classification.
Planet Finder
Sky Notes
Kilroy: Sky Notes · generated 2026-10-23 21:28:47 UTC
ISO 2025-W52 runs from December 22 through December 28. Saturn and Neptune are separated by about 3.8° in geocentric ecliptic longitude at the Monday 00:00 UTC snapshot. Mercury is about 4.0° in ecliptic longitude from Antares in Scorpius.
Naked eye: 🌓 First Quarter — 19:09:51 UTC. Moderate moonlight makes timing and local sky position important for faint targets. Use Menkar, Algol, Mirfak as the week’s fixed-sky framework.
Planets: Moon: Naked eye; magnitude -6.1; direct motion; 3.6% illuminated. Below the horizon at 21:00 local apparent solar time, 45°N. Monday 00:00 UTC snapshot. Conjunction with Ceres in ecliptic longitude Dec 27 19:02 UTC. Conjunction with Saturn in ecliptic longitude Dec 27 00:41 UTC. Conjunction with Neptune in ecliptic longitude Dec 27 07:03 UTC. Conjunction with Pluto in ecliptic longitude Dec 22 20:36 UTC. Mercury: In solar glare; magnitude -0.5; direct motion; 88.0% illuminated. Monday 00:00 UTC snapshot. Venus: In solar glare; magnitude -3.9; direct motion; 99.8% illuminated. Monday 00:00 UTC snapshot. Mars: In solar glare; magnitude 1.2; direct motion; 99.9% illuminated. Monday 00:00 UTC snapshot. Ceres: Telescope; magnitude 8.8; direct motion; 97.0% illuminated. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 27 19:02 UTC. Jupiter: Naked eye; magnitude -2.6; retrograde motion; 99.9% illuminated. Monday 00:00 UTC snapshot. Saturn: Naked eye; magnitude 1.0; direct motion; 99.7% illuminated. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 27 00:41 UTC. Uranus: Binoculars; magnitude 5.6; retrograde motion; 100.0% illuminated. Monday 00:00 UTC snapshot. Neptune: Telescope; magnitude 7.8; direct motion; 100.0% illuminated. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 27 07:03 UTC. Pluto: Substantial telescope; magnitude 14.6; direct motion; 100.0% illuminated. Below the horizon at 21:00 local apparent solar time, 45°N. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 22 20:36 UTC.
Binoculars: Trace Fornax’s charted figure in the finder, then identify Fornacis at its charted position.
Small telescope: Arp 41: consult its dedicated finder and observing story for equipment guidance; PN G138.8+02.8: consult its dedicated finder and observing story for equipment guidance; NGC 1261: consult its dedicated finder and observing story for equipment guidance; Perseus A: consult its dedicated finder and observing story for equipment guidance
Substantial telescope: No fixed-sky Calendar object is classified as requiring a substantial telescope this week.
Other objects listed this week: None
Mercury
Mercury: in solar glare at the Monday 00:00 UTC snapshot. Rises 06:19; sets 15:18 (45°N, local apparent solar time). Visual magnitude -0.5. The disk is 88.0% illuminated (gibbous). It is 16.7° from the Sun, on its west side. Motion is direct at 1.452° per day in ecliptic longitude at the snapshot. Position reference: Antares, 6.3° away. Mercury: 6.3° from Antares in the Pathfinder.
Venus
Venus: in solar glare at the Monday 00:00 UTC snapshot. Rises 07:23; sets 16:04 (45°N, local apparent solar time). Visual magnitude -3.9. The disk is 99.8% illuminated (nearly full). It is 3.8° from the Sun, on its west side. Motion is direct at 1.259° per day in ecliptic longitude at the snapshot. Position reference: Sabik, 11.0° away. Venus: 11.0° from Sabik in the Pathfinder.
Moon
Moon: naked eye at the Monday 00:00 UTC snapshot. At 45°N and 21:00 local apparent solar time, it is 32.3° below the horizon. Rises 09:25; sets 17:46 (45°N, local apparent solar time). Visual magnitude -6.1. The disk is 3.6% illuminated (waxing crescent). It is 21.8° from the Sun, on its east side. Motion is direct at 12.273° per day in ecliptic longitude at the snapshot. Position reference: Nunki, 9.1° away. Conjunction with Ceres in ecliptic longitude Dec 27 19:02 UTC. Conjunction with Saturn in ecliptic longitude Dec 27 00:41 UTC. Conjunction with Neptune in ecliptic longitude Dec 27 07:03 UTC. Conjunction with Pluto in ecliptic longitude Dec 22 20:36 UTC. Moon: 9.1° from Nunki in the Pathfinder.
Mars
Mars: in solar glare at the Monday 00:00 UTC snapshot. Rises 08:03; sets 16:38 (45°N, local apparent solar time). Visual magnitude 1.2. The disk is 99.9% illuminated (nearly full). It is 4.8° from the Sun, on its east side. Motion is direct at 0.759° per day in ecliptic longitude at the snapshot. Position reference: Nunki, 8.1° away. Mars: 8.1° from Nunki in the Pathfinder.
Jupiter
Jupiter: naked eye at the Monday 00:00 UTC snapshot. At 45°N and 21:00 local apparent solar time, it is 29.8° above the horizon. Rises 17:58; sets 09:14 (45°N, local apparent solar time). Visual magnitude -2.6. The disk is 99.9% illuminated (nearly full). It is 157.8° from the Sun, on its west side. Motion is retrograde at 0.117° per day in ecliptic longitude at the snapshot. Position reference: Pollux, 6.5° away. Jupiter: 6.5° from Pollux in the Pathfinder.
Saturn
Saturn: naked eye at the Monday 00:00 UTC snapshot. At 45°N and 21:00 local apparent solar time, it is 24.8° above the horizon. Rises 11:59; sets 23:34 (45°N, local apparent solar time). Visual magnitude 1.0. The disk is 99.7% illuminated (nearly full). It is 85.3° from the Sun, on its east side. Motion is direct at 0.042° per day in ecliptic longitude at the snapshot. Position reference: Fumalsamakah, 13.2° away. Neptune is 3.9° away at the snapshot. Conjunction with Moon in ecliptic longitude Dec 27 00:41 UTC. Saturn: 13.2° from Fumalsamakah in the Pathfinder.
Uranus
Uranus: binoculars at the Monday 00:00 UTC snapshot. At 45°N and 21:00 local apparent solar time, it is 63.0° above the horizon. Rises 14:16; sets 05:09 (45°N, local apparent solar time). Visual magnitude 5.6. The disk is 100.0% illuminated (nearly full). It is 147.9° from the Sun, on its east side. Motion is retrograde at 0.034° per day in ecliptic longitude at the snapshot. Position reference: Aldebaran, 13.0° away. Uranus: 13.0° from Aldebaran in the Pathfinder.
Neptune
Neptune: telescope at the Monday 00:00 UTC snapshot. At 45°N and 21:00 local apparent solar time, it is 28.5° above the horizon. Rises 12:02; sets 23:55 (45°N, local apparent solar time). Visual magnitude 7.8. The disk is 100.0% illuminated (nearly full). It is 89.0° from the Sun, on its east side. Motion is direct at 0.007° per day in ecliptic longitude at the snapshot. Position reference: Fumalsamakah, 14.7° away. Saturn is 3.9° away at the snapshot. Conjunction with Moon in ecliptic longitude Dec 27 07:03 UTC. Neptune: 14.7° from Fumalsamakah in the Pathfinder.
Ceres
Ceres: telescope at the Monday 00:00 UTC snapshot. At 45°N and 21:00 local apparent solar time, it is 28.5° above the horizon. Rises 12:57; sets 00:08 (45°N, local apparent solar time). Visual magnitude 8.8. The disk is 97.0% illuminated (gibbous). It is 94.7° from the Sun, on its east side. Motion is direct at 0.168° per day in ecliptic longitude at the snapshot. Position reference: Diphda, 11.4° away. Conjunction with Moon in ecliptic longitude Dec 27 19:02 UTC. Ceres: 11.4° from Diphda in the Pathfinder.
Pluto
Pluto: substantial telescope at the Monday 00:00 UTC snapshot. At 45°N and 21:00 local apparent solar time, it is 23.0° below the horizon. Rises 09:59; sets 18:42 (45°N, local apparent solar time). Visual magnitude 14.6. The disk is 100.0% illuminated (nearly full). It is 32.2° from the Sun, on its east side. Motion is direct at 0.028° per day in ecliptic longitude at the snapshot. Position reference: Dabih, 8.6° away. Conjunction with Moon in ecliptic longitude Dec 22 20:36 UTC. Pluto: 8.6° from Dabih in the Pathfinder.
Highlights
Mercury
In solar glare; magnitude -0.5; direct motion; 88.0% illuminated. Monday 00:00 UTC snapshot. Mercury: 6.3° from Antares in the Pathfinder.
Venus
In solar glare; magnitude -3.9; direct motion; 99.8% illuminated. Monday 00:00 UTC snapshot. Venus: 11.0° from Sabik in the Pathfinder.
Moon
Naked eye; magnitude -6.1; direct motion; 3.6% illuminated. Below the horizon at 21:00 local apparent solar time, 45°N. Monday 00:00 UTC snapshot. Conjunction with Ceres in ecliptic longitude Dec 27 19:02 UTC. Conjunction with Saturn in ecliptic longitude Dec 27 00:41 UTC. Conjunction with Neptune in ecliptic longitude Dec 27 07:03 UTC. Conjunction with Pluto in ecliptic longitude Dec 22 20:36 UTC. Moon: 9.1° from Nunki in the Pathfinder.
Mars
In solar glare; magnitude 1.2; direct motion; 99.9% illuminated. Monday 00:00 UTC snapshot. Mars: 8.1° from Nunki in the Pathfinder.
Jupiter
Naked eye; magnitude -2.6; retrograde motion; 99.9% illuminated. Monday 00:00 UTC snapshot. Jupiter: 6.5° from Pollux in the Pathfinder.
Saturn
Naked eye; magnitude 1.0; direct motion; 99.7% illuminated. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 27 00:41 UTC. Saturn: 13.2° from Fumalsamakah in the Pathfinder.
Uranus
Binoculars; magnitude 5.6; retrograde motion; 100.0% illuminated. Monday 00:00 UTC snapshot. Uranus: 13.0° from Aldebaran in the Pathfinder.
Neptune
Telescope; magnitude 7.8; direct motion; 100.0% illuminated. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 27 07:03 UTC. Neptune: 14.7° from Fumalsamakah in the Pathfinder.
Ceres
Telescope; magnitude 8.8; direct motion; 97.0% illuminated. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 27 19:02 UTC. Ceres: 11.4° from Diphda in the Pathfinder.
Pluto
Substantial telescope; magnitude 14.6; direct motion; 100.0% illuminated. Below the horizon at 21:00 local apparent solar time, 45°N. Monday 00:00 UTC snapshot. Conjunction with Moon in ecliptic longitude Dec 22 20:36 UTC. Pluto: 8.6° from Dabih in the Pathfinder.