Riverside Stargazing & Astronomy Report

Key Sky Quality Metrics

SQM (mag/arcsec²)

17.85

Bortle class

Class 9 (Class 9)

Darkness Quotient

22%

Dataset

May 2026

Inner city sky

Riverside: The Practical Verdict

Riverside, a mid-size city in California, sits in an area heavily impacted by light pollution. The sky quality here is severely compromised, categorised as a Bortle Class 9, indicating an inner city sky. Most deep-sky observing efforts are thwarted by the intense glow, leaving only brighter celestial objects visible.

The sky above Riverside reveals little beyond the bright planets, the Moon, bright stars, and double stars. The Milky Way is not visible under these conditions. For those practising narrowband imaging, capturing brighter nebulae is possible, but visual deep-sky observing should be avoided here.

For a true stargazing experience, consider heading to Los Angeles County to the south-west, which offers a significantly darker Bortle Class 3 sky. It's a longer drive but worth it for enthusiasts keen on serious deep-sky observation.

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

Los Angeles County, California sits about 155 km south west and reaches Bortle 3, roughly 33x darker.

Good dark window

Riverside'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 Riverside?

No. Riverside is a Bortle Class 9 sky with SQM 17.85, 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 Riverside?

Riverside is Bortle Class 9 (SQM 17.85), a severe urban sky for astronomy.

Is Riverside good for stargazing?

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

Is Riverside good for astrophotography?

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

What can you observe from Riverside?

Primary targets from Riverside 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 Riverside?

The closest meaningfully darker mapped site is Keenbrook, California, about 30 km west of Riverside, reaching Bortle 7.

When is the sky darkest in Riverside?

The sky over Riverside is darkest around January, December.

Is light pollution in Riverside getting better or worse?

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

• Keenbrook, California

  Direction

  W

  Distance (km)

  30.2

  SQM

  18.93

  Bortle

  7

• Fallbrook, California

  Direction

  S

  Distance (km)

  62.8

  SQM

  19.64

  Bortle

  6

• Los Angeles County, California

  Direction

  NNW

  Distance (km)

  93.2

  SQM

  20.25

  Bortle

  6

• Los Angeles County, California

  Direction

  SW

  Distance (km)

  155

  SQM

  21.65

  Bortle

  3

• Kelso Road, California

  Direction

  NE

  Distance (km)

  189.3

  SQM

  20.58

  Bortle

  5