YozoraAtlas
City in Oregon

How dark is the sky in Portland?

Coordinates
Satellite data year 2025 · Clear-night record 2014 to 2023
Zenith sky brightness, moonless night
mag/arcsec²
22.0 pristine16.0 city center
Bortle class
Artificial light adds to the natural brightness of the sky overhead.
Nearest dark sky

Where is the nearest dark sky to Portland?

Light map · 50 km around Portland

Lights around Portland seen from orbit

NASA satellite image of light at night, 2025. The rings mark distances from Portland.

Where are the darkest skies near Portland?

The darkest places you can drive to, up to 50, 100 and 150 km from Portland. Roadless country nearby can be darker still.

    A spot closed at night, or a number that looks wrong? Let us know.

    Satellite night-light map of the 50 km around Portland, with Vancouver, Beaverton and Gresham marked
    Radiance, nW/cm²/sr
    0110300+
    Light domes · where the glow comes from

    Which towns light up the Portland horizon?

    The compass shows where the glow on the horizon comes from, counting all light more than 5 km away. The table names the towns behind it, including Portland's own outskirts.

    SourceDistanceShare

    The horizon in Portland, all 360°, brighter where more glow arrives
    NNEESESSWWNWN
    2012 to 2025

    Has the sky over Portland gotten brighter?

    Each point is how much artificial light added to the natural brightness of the sky overhead that year: 0% is a natural sky, 100% means twice as bright. Same satellite every year; it barely sees the blue part of white LED light, so recent years probably read too dark.

    Nightly cloud record 2014 to 2023

    Clear nights in Portland by month

    The average number of nights each month with less than 30% cloud, from NASA POWER satellite records.

    Calculated in advance for 2027 · not a weather forecast

    When is Milky Way season near Portland in 2027?

    Nights in each month when the Milky Way core stands more than 10° above the horizon for at least an hour of moonless astronomical darkness. At 45.5° north the core peaks at about 15° high, so a clear southern horizon matters. These are calculated positions of the sun, moon and Milky Way; whether a night is clear is only known closer to the date.

    Expected best nights in 2027, combining moonless darkness, Milky Way core time and average clear-night odds
    New moons 2027, calculated