9:14 PMAstronomical twilight ends. Deep sky objects optimal.
11:30 PMJupiter at meridian. Best viewing window opens.
1:15 AMMilky Way core rises to 28° above horizon.
3:42 AMSeeing peaks — optimal imaging window begins.
Deep Sky Targets
Best objects visible from — tonight
OBJECT OF THE NIGHT
M31 — Andromeda Galaxy
GalaxyMag 3.4AndromedaAlt 68° — Excellent
The nearest major galaxy to the Milky Way at 2.537 million light-years. Visible to the naked eye under dark skies and spectacular in binoculars. Tonight it transits at 10:42 PM reaching 72° altitude — prime position all night.
2.537 MLy
Distance
3.4
Magnitude
10:42 PM
Transit
72°
Max Alt
Tonight's Catalog
Object
Type
Const.
Mag
Size
Alt Now
Best Window
M31 Andromeda
Galaxy
And
3.4
3°×1°
68°
9 PM – 1 AM
M33 Triangulum
Galaxy
Tri
5.7
67′
62°
10 PM – 2 AM
M42 Orion Nebula
Nebula
Ori
4.0
65′
34°
12 AM – 4 AM
M45 Pleiades
Cluster
Tau
1.6
110′
52°
9 PM – 3 AM
M81 Bode's Galaxy
Galaxy
UMa
6.9
21′
48°
10 PM – 4 AM
M57 Ring Nebula
Nebula
Lyr
8.8
1.5′
41°
9 PM – 11 PM
M13 Hercules Cluster
Cluster
Her
5.8
20′
38°
9 PM – 12 AM
M27 Dumbbell Nebula
Nebula
Vul
7.5
8′
55°
10 PM – 1 AM
M51 Whirlpool Galaxy
Galaxy
CVn
8.4
11′
44°
11 PM – 3 AM
M35 Open Cluster
Cluster
Gem
5.1
28′
43°
11 PM – 3 AM
Satellite Passes
Visible overhead passes for — tonight
NEXT ISS PASS
10:48 PM
in 2h 34m
72°
Max Elevation
-3.8
Magnitude
5 min
Visible
SW → NNE · Rises 10:48 PM · Sets 10:53 PM
ISS Passes Tonight
Object
Rise
Max Elev.
Set
Duration
Direction
Visibility
Search a location to load pass predictions
Times are local · Passes with max elevation <10° omitted · Source: Celestrak TLE + satellite.js
Constellation Guide
Visibility and best viewing times for your location
Orion Ori
Winter · Best Dec–Mar
One of the most recognizable constellations, visible worldwide. Home to the Orion Nebula, …
RA 5h 35mDec -5°Best DSO M42 Orion Nebula
Best viewing: Dec–Mar
Notable Stars: Betelgeuse, Rigel, Alnitak
Ursa Major UMa
All Year · Best Mar–Jun
Home to the Big Dipper asterism and two spectacular spiral galaxies M81 and M82. Circumpol…
RA 10h 40mDec 56°Best DSO M81 Bode's Galaxy
Best viewing: Mar–Jun
Notable Stars: Dubhe, Merak, Alioth
Gemini Gem
Winter · Best Dec–Mar
The Twins constellation dominated by the bright pair Castor and Pollux. Radiant of the ann…
RA 7h 30mDec 25°Best DSO M35 Open Cluster
Best viewing: Dec–Mar
Notable Stars: Castor, Pollux
Taurus Tau
Winter · Best Nov–Mar
The Bull hosts the Pleiades star cluster and the Crab Nebula supernova remnant. Aldebaran …
RA 4h 42mDec 15°Best DSO M45 Pleiades, M1 Crab
Best viewing: Nov–Mar
Notable Stars: Aldebaran, Alcyone (Pleiades)
Leo Leo
Spring · Best Feb–May
A prominent spring constellation shaped like a crouching lion. Regulus lies almost exactly…
RA 10h 40mDec 15°Best DSO M95, M96 Galaxy Group
Best viewing: Feb–May
Notable Stars: Regulus, Algieba, Denebola
Virgo Vir
Spring · Best Mar–Jun
The largest constellation in area. Contains the Virgo Cluster — the nearest large galaxy c…
RA 13h 25mDec -5°Best DSO Virgo Galaxy Cluster
Best viewing: Mar–Jun
Notable Stars: Spica, Vindemiatrix
Libra Lib
Spring · Best Apr–Jul
The Scales — the only zodiac constellation representing an inanimate object. Its two main …
RA 15h 12mDec -15°Best DSO NGC 5897 Globular
Best viewing: Apr–Jul
Notable Stars: Zubenelgenubi, Zubeneschamali
Scorpius Sco
Summer · Best Jun–Aug
A stunning summer constellation best seen from southern latitudes. Its heart star Antares …
RA 16h 53mDec -30°Best DSO M6 Butterfly Cluster
Best viewing: Jun–Aug
Notable Stars: Antares, Shaula
Sagittarius Sgr
Summer · Best Jul–Sep
Points toward the Galactic Center — the richest part of the Milky Way. Contains more Messi…
RA 18h 55mDec -28°Best DSO M8 Lagoon Nebula
Best viewing: Jul–Sep
Notable Stars: Kaus Australis, Nunki
Capricornus Cap
Autumn · Best Aug–Oct
The Sea Goat — a faint zodiac constellation best seen in early autumn. Despite its faintne…
RA 21h 0mDec -20°Best DSO M30 Globular Cluster
Best viewing: Aug–Oct
Notable Stars: Deneb Algedi, Dabih
Aquarius Aqr
Autumn · Best Sep–Nov
The Water Bearer houses the magnificent Helix Nebula — the nearest planetary nebula to Ear…
RA 22h 18mDec -10°Best DSO NGC 7293 Helix Nebula
Best viewing: Sep–Nov
Notable Stars: Sadalsuud, Sadalmelik
Pisces Psc
Autumn · Best Oct–Dec
The Fish — a faint but large zodiac constellation. The vernal equinox currently lies withi…
RA 0h 30mDec 15°Best DSO NGC 628 Messier 74
Best viewing: Oct–Dec
Notable Stars: Eta Piscium, Alrescha
Aries Ari
Autumn · Best Nov–Jan
The Ram — a small but historically important zodiac constellation. Mesarthim was one of th…
RA 2h 38mDec 20°Best DSO NGC 697
Best viewing: Nov–Jan
Notable Stars: Hamal, Sheratan, Mesarthim
Cancer Cnc
Winter · Best Jan–Apr
The faintest zodiac constellation but home to the Beehive Cluster (M44), one of the closes…
RA 8h 40mDec 20°Best DSO M44 Beehive Cluster
Best viewing: Jan–Apr
Notable Stars: Asellus Borealis, Acubens
Astrophotography Planner
Imaging windows and settings for your location tonight
Andromeda Galaxy
M31 · Galaxy
Beginner
Our nearest large neighbor. Wide-field imaging reveals its full structure with dark dust lanes. Minimal processing needed.
2.537 MLy
Distance
300–600mm
Focal Length
2–5 min
Exposure
ISO 800
ISO
Orion Nebula
M42 · Emission Nebula
Beginner
The brightest nebula in the sky. The Trapezium cluster in its core burns bright — use short exposures to avoid overexposure.
1,344 ly
Distance
400–800mm
Focal Length
30–120s
Exposure
ISO 400
ISO
Lagoon Nebula
M8 · Emission Nebula
Intermediate
A stunning red nebula best captured with Hα narrowband filters. Pairs beautifully with the nearby Trifid Nebula M20.
4,100 ly
Distance
300–600mm
Focal Length
3–8 min
Exposure
ISO 800
ISO
Crab Nebula
M1 · Supernova Remnant
Advanced
Remnant of a supernova observed in 1054 AD. Its filamentary structure requires long exposures and good seeing conditions.
6,500 ly
Distance
1000mm+
Focal Length
5–15 min
Exposure
ISO 1600
ISO
Eagle Nebula
M16 · Emission Nebula
Intermediate
Home of the famous Pillars of Creation. Best captured with narrowband Hα filters to reveal the intricate dust pillars.
7,000 ly
Distance
600–1200mm
Focal Length
5–10 min
Exposure
ISO 1600
ISO
Ring Nebula
M57 · Planetary Nebula
Advanced
A perfect smoke ring 1 light-year across. Requires long focal lengths to resolve its central white dwarf star.
2,300 ly
Distance
1500mm+
Focal Length
3–8 min
Exposure
ISO 800
ISO
Helix Nebula
NGC 7293 · Planetary Nebula
Intermediate
The nearest planetary nebula and largest in angular size. Low surface brightness demands dark skies and long integrations.
650 ly
Distance
300–600mm
Focal Length
5–15 min
Exposure
ISO 1600
ISO
Horsehead Nebula
B33 · Dark Nebula
Advanced
A dark nebula silhouetted against emission nebula IC 434. Nearly impossible without Hα filters and excellent dark skies.
1,500 ly
Distance
600–1200mm
Focal Length
10–20 min
Exposure
ISO 3200
ISO
Carina Nebula
NGC 3372 · Emission Nebula
Intermediate
One of the largest and brightest nebulae in the sky — only visible from the Southern Hemisphere. Contains Eta Carinae.
7,500 ly
Distance
200–400mm
Focal Length
3–10 min
Exposure
ISO 800
ISO
Tarantula Nebula
30 Dor · Emission Nebula
Intermediate
The most active star-forming region in the Local Group, located in the Large Magellanic Cloud. Southern hemisphere only.
160,000 ly
Distance
300–800mm
Focal Length
5–15 min
Exposure
ISO 1600
ISO
Dark Site Finder
Light pollution levels and nearest dark skies from your location
YOUR LOCATION
—
Search a location to load
SQM: — · Mag limit: —
Nearest darker skies
~45 mi
Bortle 3–4
~90 mi
Bortle 2
~150 mi
Bortle 1
Bortle Scale
1 Darkest9 Brightest
The Bortle Scale Explained
Class 1
Zodiacal Light visible
Truly dark sky
The Zodiacal Light is prominent and M33 is visible with the naked eye. The gegenschein is easily seen.
Class 2
Typical dark site
Truly dark sky
Airglow weakly visible near horizon. M33 directly visible with averted vision. Milky Way shows extensive structure.
Class 3
Rural sky
Rural
Some light pollution domes visible on horizon. Milky Way shows complex structure overhead. M33 easily visible.
Class 4
Rural/suburban
Rural/suburban
Light pollution visible in several directions. Milky Way is still impressive but lacks detail near horizon.
Class 5
Suburban sky
Suburban
Milky Way is washed out near horizon. Light pollution glow obvious in multiple directions. M33 difficult.
Class 6
Bright suburban
Bright suburban
Milky Way only visible near zenith. Most Messier objects easily visible with binoculars.
Class 7
Suburban/urban
Suburban/urban
Sky background gray to orange. Milky Way barely visible. Bright Messier objects visible in small telescopes.
Class 8
City sky
Urban
Sky background is bright orange to white. The Milky Way is invisible, and only the brightest deep-sky objects remain practical.
Class 9
City sky
Urban
Sky is bright gray or orange. Milky Way invisible. Only bright clusters and double stars observable.
Tips for Finding Dark Skies
Time it right New moon nights offer the darkest skies. The 5 nights before and after new moon add roughly 20% more observable sky.
Head north or west In the Northern Hemisphere, light pollution domes typically stretch east from population centers. Driving into rural areas to the west often yields the fastest improvement.
Elevation helps Gaining elevation reduces the atmosphere column above you and puts you above valley haze and light domes. Even 2,000 ft makes a measurable difference in transparency.
Let your eyes adapt Full dark adaptation takes 20–30 minutes. Avoid white light completely; use a red flashlight. Your sensitivity can increase up to 100,000× during this period.
Lunar Anatomy
Surface features, maria, and impact craters of Earth's Moon
Surface Feature MapFull Moon Reference
Maria (Seas)
Dark basaltic plains formed by ancient volcanic eruptions 3–4 billion years ago. Named by early astronomers who mistook them for actual seas. They cover about 16% of the lunar surface, predominantly on the near side.
Mare TranquillitatisMare ImbriumOceanus ProcellarumMare SerenitatisMare CrisiumMare Nubium
Impact Craters
Bowl-shaped depressions formed by meteorite impacts over 4 billion years. Prominent craters often show bright ray systems — streaks of ejecta that extend hundreds of kilometers. Over 300,000 craters larger than 1 km exist.
The Moon's terminator — the line between light and shadow — is the best zone for observing surface relief. Craters and mountains cast dramatic shadows there. First and last quarter phases offer prime conditions; avoid full moon for detail work.
Use 50–200× magnificationStudy the terminatorSketch what you seeTry a lunar filter
Quick Facts
384,400 km
Avg Distance
3,474 km
Diameter
29.5 days
Synodic Period
-12.7
Max Magnitude
1.62 m/s²
Surface Gravity
4.5 Byr
Age
Map of Light Pollution
Regional light-pollution view centered on your location
About AstronoSight
How the forecast works and where the data comes from
Frequently Asked Questions
What does the Antoniadi scale mean for Seeing?
The Antoniadi scale rates atmospheric stability from I (perfect, no quivering) to V (very bad, barely allows rough sketching). A score of III or better is generally needed for planetary detail work. AstronoSight converts this to a 0–100 sub-score for the composite.
How often is the forecast updated?
Weather data refreshes every 15 minutes automatically after your first search. The Bortle class is derived from a curated 503-city database calibrated to NOAA VIIRS satellite data and does not require a live API call.
Why does my score differ from Clear Outside or Clear Dark Sky?
Different services weight factors differently and use different numerical weather models. AstronoSight emphasises cloud cover and atmospheric seeing most heavily since these dominate the visual experience. Cross-referencing multiple sources is recommended for critical sessions.
What is the Bortle scale and how does it affect my score?
The Bortle scale (1–9) measures sky brightness — 1 is truly dark desert sky, 9 is inner city. AstronoSight looks up your location against a 503-city database calibrated to NOAA VIIRS nighttime satellite radiance. Light pollution carries 8% weight in the viewing score, so a Bortle 9 city loses roughly 8 points vs a Bortle 1 dark sky, all else equal.
What does "Dark Until" mean on the forecast card?
"Dark Until" shows the end of astronomical twilight — when the Sun drops 18° below the horizon and the sky reaches true nighttime darkness. Before this time, scattered sunlight still washes out faint nebulae and galaxies. Calculated in real time by Astronomy Engine for your exact coordinates and date.
How accurate are the ISS pass predictions?
ISS passes use fresh TLE data from Celestrak, propagated with satellite.js SGP4 in your browser. Accuracy is typically within 30 seconds for passes within the next 24 hours. Passes below 10° elevation are filtered out. TLE accuracy degrades slightly for passes further in the future due to atmospheric drag variability.
Can I use AstronoSight for astrophotography planning?
Yes — the Astro Planner tab lists 10 deep-sky targets with recommended focal lengths, exposures, and ISO settings. Cross-reference transparency and seeing factors to judge whether conditions suit wide-field imaging or high-resolution planetary work.
Why does the Bortle class say "Curated city DB"?
The NOAA VIIRS ArcGIS API is blocked by CORS in browser environments (it requires a server-side proxy). Rather than showing Bortle 1 for every location, AstronoSight uses an embedded 503-city database calibrated directly from published VIIRS radiance data. This gives accurate results instantly with no API calls.
Is AstronoSight free? Do I need an account?
Completely free. No account, no subscription, no ads. All APIs used (Open-Meteo, Celestrak, BigDataCloud) are free or open-source. Your location is only used to fetch real-time data and is never stored on any server.
Can I observe planets with just binoculars?
Absolutely. Venus, Mars, Jupiter, and Saturn show significant detail in 10×50 binoculars — Jupiter's four Galilean moons are visible, Saturn's rings resolve at 20×+, and Mars shows polar cap hints near opposition. The planet panel shows current altitude, magnitude, and rise/set times so you know what's accessible tonight.
What does each colour on the score ring mean?
The score ring and atmospheric factor bars use a consistent colour scale: green (≥ 80 — excellent), cyan (65–79 — good), amber (45–64 — fair), and red (below 45 — poor). The same colours appear in the 7-day weekly outlook bars and the factor list so you can instantly gauge each contributor.
How the Score Works
The Viewing Score (0–100) is a weighted composite of 9 atmospheric and environmental factors, with light pollution now carrying the largest weight. A score above 80 indicates excellent conditions for visual astronomy or astrophotography.
Light Pollution (Bortle)
50%
Cloud Cover
20%
Precipitation
8%
Moon Illumination
5%
Atmospheric Seeing
5%
Transparency
5%
Wind Speed
3%
Humidity
2%
Jet Stream
1%
Temperature
1%
4%
Bortle class is looked up from a 503-city VIIRS-calibrated database and now carries the largest share of the final score.
