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Sky Digest

Thursday, 18 December 2025 | Default Location
Showing the sky from Greenwich, London. Log in to use your own location.
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Tonight at a Glance

New Moon 1%
Dark window: 17:18 – 06:41 (13 h 23 m)

Planet Highlights

Jupiter mag -2.7 · 28° alt · Gemini Details
GRS transit tonight:
Saturn mag 0.9 · 22° alt · Aquarius Details
Rings: Edge-on (rings nearly invisible) (0.8° north face)

Comets

PANSTARRS mag 6.7 · 33° alt · Pegasus Details
bright 2.15 AU Perihelion: Apr 19 (in 19d)

For Beginners (naked eye)

Double Cluster
NGC 869 Open Cluster
mag 4.3

At 21:00 look near the zenith

Perseus
M42
Great Orion Nebula Nebula
mag 4.0

At 21:00 look low in the southeast

Orion
M31
Andromeda Galaxy Galaxy
mag 3.4

At 21:00 look high in the west

Andromeda

Binocular Targets

Mira
68 Cet Variable Star
mag 3.0

At 21:00 look halfway up in the south

Cet
M34
Spiral Cluster Open Cluster
mag 5.5

At 21:00 look near the zenith

Perseus
M33
Triangulum/Pinwheel Galaxy Galaxy
mag 5.7

At 21:00 look high in the southwest

Triangulum

Small Scopes (3–6 inch)

Castor
HIP 36850; Alpha Gem; 66 Gem Double Star
mag 2.0

At 21:00 look halfway up in the east

Gem
NGC 1245
Open Cluster
mag 8.4

At 21:00 look near the zenith

Per
M76
Little Dumbbell Nebula Planetary Nebula
mag 10.1

At 21:00 look near the zenith

Perseus
M77
Cetus A or Squid Galaxy Galaxy
mag 8.9

At 21:00 look halfway up in the south

Cetus
R Tri
Variable Star
mag 5.3

At 21:00 look near the zenith

Tri

Big Scopes (8–12 inch)

NGC 1220
Open Cluster
mag 12.0

At 21:00 look near the zenith

Per
C56
NGC 246 Planetary Nebula
mag 10.9

At 21:00 look low in the southwest

Cetus
C23
NGC 891 Galaxy
mag 9.9

At 21:00 look near the zenith

Andromeda
NGC 925
Galaxy
mag 10.0

At 21:00 look near the zenith

Tri
NGC 891
Galaxy
mag 10.0

At 21:00 look near the zenith

And

The Week Ahead

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NASA Astronomy Picture of the Day

Jupiter and the Meteors from Gemini

Jupiter, the Solar System's ruling gas giant, is the brightest celestial beacon at the center of this composite night skyscape. The scene was constructed by selecting the 40 exposures containing meteors from about 500 exposures made on the nights of December 13 and 14, near peak activity for this year's annual Geminid meteor shower. With each selected exposure registered in the night sky above Alentejo, Portugal, planet Earth, it does look like the meteors are streaming away from Jupiter. But the apparent radiant of the Geminid meteors is actually closer to bright star Castor, in the shower's eponymous constellation Gemini. In this frame that's just a little above and left of the Solar System's most massive planet. Still, the parent body of Geminid meteors is known to be rocky, near-Earth asteroid 3200 Phaethon. And the orbit of Phaethon itself is influenced by the gravitational attraction exerted by massive Jupiter, in concert with planets of the inner Solar System.

Image credit: David Cruz — APOD is a service of NASA and Michigan Tech. U.

View on NASA APOD

Space News

Watch live: Artemis II launch

Artemis II, the first crewed mission to the Moon in over 50 years, is scheduled to launch on April 1, 2026, carrying four astronauts on a historic 10-day journey around the Moon and back to Earth.

ESA — 31 Mar 2026

Europe's engines powering Artemis II

Europe's Service Module, built by ESA and equipped with 33 engines, will provide critical propulsion, power, and life support for the Artemis II spacecraft during its crewed lunar mission.

ESA — 30 Mar 2026

NASA Selects Intuitive Machines to Deliver Artemis Science, Tech to Moon

NASA awarded Intuitive Machines $180.4 million to deliver NASA-funded science payloads to the lunar surface as part of the Commercial Lunar Payload Services initiative supporting the Artemis program.

NASA — 27 Mar 2026

European eyes on Artemis

Artemis II will carry not only four astronauts but also European engineers and medical specialists, with the European Service Module as a key component powering humanity's return to lunar exploration.

ESA — 31 Mar 2026

Plan your session before dark

Use Tonight to find targets, then add them to a Plan so you have a checklist ready when you're outside.

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