Phoenix Stargazing & Astronomy Report

Light pollution and stargazing locations near Phoenix

City
Phoenix
Country
United States
Latitude
33.4484
Longitude
-112.0740

Key Sky Quality Metrics

SQM (mag/arcsec²)
17.27
Bortle class
Class 9 (Class 9)
Darkness Quotient
18%
Dataset
March 2026

Inner city sky

Phoenix: The Practical Verdict

Phoenix is a vast desert metropolis in the south-western United States, the capital of Arizona and the dominant urban centre of the Sonoran Desert.

The city generally experiences Extreme Light Pollution, with a Darkness Quotient of just 18% — placing it among the more light-polluted major cities in North America.

For practical observing from within the city, the strongest targets are the Moon, planets, double stars and the brightest open clusters. A few showpiece deep-sky objects can still be attempted with care, but faint galaxies, nebulae and the Milky Way are largely washed out by the city glow.

Genuinely darker skies require a fairly substantial drive from Phoenix. The nearest strong improvement is about 165 kilometres to the south-south-west, near Pima County, Arizona, where conditions become properly dark by amateur standards.

The map shows Phoenix as an intense pink-white core surrounded by a broad red, yellow and green halo, which is exactly what you would expect from a very large metropolitan area spilling light far into the surrounding desert.

That halo does not fade evenly in every direction: there are many smaller bright patches scattered around the wider region, showing how outlying settlements and development extend the glow beyond the main urban mass. Even so, the darkest-looking areas on the crop sit well away from the city, especially toward the outer eastern side and parts of the wider northern and southern outskirts where the colours finally drop through blue into near-black.

In other words, Phoenix is dramatically brighter than its immediate surroundings, but the surrounding desert does eventually allow a real escape from the worst of the glow once you get far enough from the metro area.

How the sky is likely to look overhead

Looking straight up from Phoenix, the sky is bright enough that it rarely feels truly dark even when transparent and moonless. The background glow tends to flatten contrast, so the sky takes on more of a luminous urban grey than a rich black desert canopy.

The brighter constellations still come through, and familiar patterns can be picked out without much difficulty once your eyes adapt. What is missing is depth: dimmer stars fade quickly, the Milky Way is effectively lost, and subtle structure in richer star fields is overwhelmed by the city glow.

For casual skywatching that still leaves plenty to enjoy, especially the Moon and planets. For deep-sky observing, though, the zenith from within the city is strongly compromised and rewards even a moderate move away from the urban core.

north - poor

About 15 kilometres north of the city, the sky is still poor, around Bortle 8, so the urban glow remains very obvious. Conditions improve markedly farther out, with genuinely dark skies reached at roughly 100 kilometres in this direction.

north-north-east - poor

Around 15 kilometres north-north-east, conditions are still poor at about Bortle 8, with only limited relief from Phoenix's light dome. A much better result comes farther out, with dark skies appearing at around 100 kilometres.

north-east - poor

At roughly 15 kilometres to the north-east, the sky remains poor and heavily affected by city light, at about Bortle 8. Continue outward and this direction becomes much more attractive, reaching dark conditions at around 100 kilometres.

east-north-east - poor

Fifteen kilometres east-north-east is still firmly poor, with a Bortle 9 sky little better than the city itself. The improvement comes later here, but by around 100 kilometres this direction reaches properly dark skies.

east - poor

A quick move east leaves you under a poor sky at about 15 kilometres, still around Bortle 9. This direction does improve steadily, reaching good skies by about 100 kilometres and genuinely excellent darkness farther out at around 200 kilometres.

east-south-east - poor

At around 15 kilometres east-south-east, the sky is still poor at Bortle 9 and strongly dominated by urban glow. Much darker conditions are available farther out, with dark-sky territory reached at about 100 kilometres.

south-east - poor

Fifteen kilometres south-east of Phoenix, the sky is still poor at Bortle 9, so this is not yet a meaningful escape from the city. It does improve to good territory farther out, at around 100 kilometres, but genuinely dark skies are not reached within the sampled distance in this direction.

south-south-east - poor

Around 15 kilometres south-south-east, the sky is poor at about Bortle 8, though it is beginning to loosen its grip compared with the city centre. This direction keeps improving, with good conditions around 100 kilometres and genuinely dark skies by roughly 200 kilometres.

south - poor

At 15 kilometres south, conditions are still poor, around Bortle 7, with a noticeable light dome behind you. The route improves in a useful, steady way and reaches genuinely dark skies at about 100 kilometres.

south-south-west - poor

Roughly 15 kilometres south-south-west, the sky is still poor at about Bortle 7, but it is one of the more encouraging short-hop directions from Phoenix. By around 50 kilometres conditions are already good, and truly dark skies arrive at about 100 kilometres.

south-west - poor

At around 15 kilometres south-west, the sky remains poor at Bortle 7, though it is beginning to improve from the city centre baseline. This becomes a strong direction farther out, with good skies by about 50 kilometres and dark skies at around 100 kilometres.

west-south-west - poor

Fifteen kilometres west-south-west still leaves you under a poor Bortle 8 sky with heavy urban influence. The gain is much clearer farther out, with dark conditions reached at around 100 kilometres.

west - poor

A short drive west does little at first: around 15 kilometres out the sky is still poor at Bortle 9. Better conditions appear only well beyond the metro glow, with dark skies reached at about 100 kilometres.

west-north-west - poor

At roughly 15 kilometres west-north-west, the sky is still poor and close to Bortle 9, so deep-sky observing remains heavily compromised. A proper improvement requires a longer run, with dark skies reached around 100 kilometres out.

north-west - poor

Fifteen kilometres north-west of Phoenix still gives a poor Bortle 9 sky with strong residual glow. This direction improves later on, with genuinely dark conditions appearing at about 100 kilometres.

north-north-west - poor

Around 15 kilometres north-north-west, the sky is poor at about Bortle 8 and still very much urban in character. If you keep going, this direction becomes much better, reaching dark skies at roughly 100 kilometres.

zenith - poor

Straight overhead from Phoenix, the zenith is poor, with a Bortle 9 sky and an SQM reading of 17.27. The brightest constellations, planets and the Moon are easy enough to follow, but the background sky remains bright and the Milky Way is effectively lost from view.

  • Near Pima County, Arizona
    Direction
    SSW
    Distance (km)
    167.3
    SQM
    21.62
    Bortle
    3

    Milky Way visible, broadband DSO imaging

  • Near Tubutama, Sonora
    Direction
    SSE
    Distance (km)
    283.6
    SQM
    21.56
    Bortle
    3

    Milky Way visible, broadband DSO imaging

  • Near Coconino County, Arizona
    Direction
    SSW
    Distance (km)
    287.5
    SQM
    21.56
    Bortle
    3

    Milky Way visible, broadband DSO imaging

Historical Light Pollution Trends

Phoenix has shown a slight long-term brightening trend in the record, with SQM moving from 17.45 in the earliest data to 17.27 in the latest, a change consistent with gradually worsening night-sky brightness.

The overall trend slope is modest at -0.0113 SQM per year, so this is not a dramatic shift from one year to the next. Still, across 76 datasets the pattern suggests that city-centre skies have, on balance, become a little brighter rather than darker.

The recorded range is fairly tight, from 17.27 to 17.63, which tells us Phoenix has remained consistently heavily light-polluted throughout the period rather than swinging between very different observing conditions.