Corona Stargazing & Astronomy Report

Light pollution and stargazing locations near Corona

City
Corona
Country
United States
Latitude
33.8753
Longitude
-117.5664

Key Sky Quality Metrics

SQM (mag/arcsec²)
17.92
Bortle class
Class 9 (Class 9)
Darkness Quotient
22%
Dataset
April 2026

Inner city sky

Corona: The Practical Verdict

Corona, a small city in Southern California, sits under a severe urban sky. High light pollution renders it unsuitable for deep-sky astronomy or Milky Way viewing.

The diminished sky permits only the brightest objects, including planets, the Moon, and prominent double stars. While limited narrowband imaging may capture the brightest nebulae, faint galaxies and deep-sky imaging are not practical.

For significantly improved conditions, Ventura County, positioned west southwest and about 195 km away, offers an excellent upgrade with Bortle 2 skies and enhanced visibility for serious observing or imaging.

At a Glance

Overall
Severe urban sky - This is a severely light-polluted urban sky. Only the Moon, planets, bright stars, and a few specialist targets remain practical.
Milky Way
Not visible - The Milky Way is not visible from this sky.
Best targets from here
Moon, planets, bright stars, double stars, solar system events, narrowband imaging only with care
Do not prioritise
visual deep-sky observing, broadband galaxies, reflection nebulae, widefield Milky Way
Best nearby upgrade
Ventura County, California sits about 195 km west south west and reaches Bortle 2, roughly 33x darker.
Good dark window
Corona's longest dark windows fall in December and January, with the shortest nights around June and July. Plan deep-sky sessions around the autumn and winter months for the best combination of long nights and true astronomical darkness.

Frequently Asked Questions

Can you see the Milky Way from Corona?

No. Corona is a Bortle Class 9 sky with SQM 17.92, so the Milky Way is not visible from the city. For Milky Way photography, look for a Bortle 4 or darker site.

What Bortle class is Corona?

Corona is Bortle Class 9 (SQM 17.92), a severe urban sky for astronomy.

Is Corona good for stargazing?

Not for serious deep-sky observing. Corona is a severe urban sky where the Moon, planets, and a handful of bright targets are the realistic options from the city itself.

Is Corona good for astrophotography?

Broadband deep-sky imaging is heavily compromised from Corona and a Bortle 4 or darker site is strongly recommended. Even narrowband imaging is difficult from Corona without careful processing.

What can you observe from Corona?

Primary targets from Corona include Moon, planets, bright stars, double stars, solar system events. Targets such as visual deep-sky observing, broadband galaxies, reflection nebulae are not realistic from this sky.

Where are darker skies near Corona?

The closest meaningfully darker mapped site is Oso Trail, California, about 31 km south of Corona, reaching Bortle 7.

When is the sky darkest in Corona?

The sky over Corona is darkest around January, December.

Is light pollution in Corona getting better or worse?

Long-term light pollution over Corona has been broadly stable across the available measurements.

north - poor

Significant glow on the north horizon. Avoid this direction for objects below 30 degrees elevation.

north-north-east - poor

Significant glow on the north-north-east horizon. Avoid this direction for objects below 30 degrees elevation.

north-east - marginal

The lower north-east sky is moderately light-polluted. Useful for bright targets above about 20 degrees only.

east-north-east - poor

Strong artificial brightening to the east-north-east. Faint and mid-brightness stars near the horizon are absent.

east - marginal

Moderate brightening on the east horizon. Star counts at low elevation here are reduced.

east-south-east - fair

Mild brightening on the east-south-east horizon. Faint stars at the very lowest elevation are dimmed; otherwise unaffected.

south-east - fair

A small artificial brightening near the south-east horizon. Star counts in this direction remain high above the lowest elevations.

south-south-east - fair

Mild brightening on the south-south-east horizon. Faint stars at the very lowest elevation are dimmed; otherwise unaffected.

south - fair

The south horizon is mostly dark with a hint of light pollution. Faint stars are accessible above about 10 degrees.

south-south-west - fair

Subtle skyglow on the south-south-west horizon. Faint stars below about 10 degrees here are slightly suppressed.

south-west - fair

The south-west horizon shows a slight brightening. Workable for most targets above about 10 degrees elevation.

west-south-west - fair

A small artificial brightening near the west-south-west horizon. Star counts in this direction remain high above the lowest elevations.

west - marginal

Persistent skyglow on the west horizon. Faint stars near the ground in this direction are lost.

west-north-west - marginal

The lower west-north-west sky is moderately light-polluted. Useful for bright targets above about 20 degrees only.

north-west - marginal

Moderate brightening on the north-west horizon. Star counts at low elevation here are reduced.

north-north-west - marginal

Persistent skyglow on the north-north-west horizon. Faint stars near the ground in this direction are lost.

zenith - poor

Heavy skyglow overhead. A few dozen stars and the brightest planets are accessible to the naked eye.

  • Oso Trail, California
    Direction
    S
    Distance (km)
    30.6
    SQM
    19.59
    Bortle
    7
  • Cottonwood Road, California
    Direction
    WSW
    Distance (km)
    98.8
    SQM
    20.88
    Bortle
    4
  • Los Angeles County, California
    Direction
    SW
    Distance (km)
    140
    SQM
    21.64
    Bortle
    3
  • Ventura County, California
    Direction
    WSW
    Distance (km)
    195
    SQM
    21.72
    Bortle
    2
  • Santa Barbara County, California
    Direction
    W
    Distance (km)
    202.7
    SQM
    21.66
    Bortle
    3
  • Segundo, California
    Direction
    W
    Distance (km)
    268
    SQM
    21.70
    Bortle
    3