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Saturday, 20 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 · 30° alt · Gemini Details
GRS transit tonight:
Io Occultation begins
Saturn mag 0.9 · 21° alt · Aquarius Details
Rings: Edge-on (rings nearly invisible) (0.8° north face)

Comets

PANSTARRS mag 6.7 · 32° 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
M81
Bode's Galaxy Galaxy
mag 6.9

At 21:00 look halfway up in the northeast

Ursa Major

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

A Solstice Sun Tattoo

The word solstice is from the Latin for Sun and to pause or stand still. And in the days surrounding a solstice the Sun's annual north-south drift in planet Earth's sky does slow down, pause, and then reverse direction. So near the solstice the daily path of the Sun through the sky really doesn't change much. In fact, near the December solstice, the Sun's consistent, low arc through northern hemisphere skies, along with low surface temperatures, has left a noticeable imprint on this path to the mountain town of Peaio in northern Italy. The morning frost on the road has melted away only where the sunlight was able to reach the ground. But it remains in the areas persistently shadowed by the fence, tattooing in frost an image of the fence on the asphalt surface.

Image credit: Marcella Pace — 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 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 the propulsion, power, and life support systems that enable the Artemis II spacecraft to reach the Moon and return safely.

ESA — 30 Mar 2026

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

NASA has awarded Intuitive Machines $180.4 million to deliver seven science and technology payloads to the lunar surface through the Commercial Lunar Payload Services initiative in support of the Artemis program.

NASA — 27 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.

Open Tonight

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