Sioux Falls Stargazing & Astronomy Report

Key Sky Quality Metrics

SQM (mag/arcsec²)

17.74

Bortle class

Class 9 (Class 9)

Darkness Quotient

21%

Dataset

April 2026

Inner city sky

Sioux Falls: The Practical Verdict

Sioux Falls, a small city in South Dakota, features a sky severely hampered by high light pollution, typical of urban environments. Observing opportunities are limited, with a Milky Way that is entirely invisible and only the very brightest targets penetrating the city's skyglow.

From this location, stargazers can enjoy planets, the Moon, bright stars, and double stars with clarity. Narrowband imaging is feasible but will require careful planning to address the intrusive brightness. Dimmer deep-sky objects, widefield Milky Way views, and most meteor showers are not a realistic prospect under such bright conditions.

For those seeking significantly darker skies, the Middletown Township area to the east, about 140 km away, provides a Bortle 3 sky. This site is worth the drive for deep-sky observations, offering a notable improvement in sky quality.

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

Middletown Township, Minnesota sits about 141 km east and reaches Bortle 3, roughly 29x darker.

Good dark window

Sioux Falls'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 Sioux Falls?

No. Sioux Falls is a Bortle Class 9 sky with SQM 17.74, 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 Sioux Falls?

Sioux Falls is Bortle Class 9 (SQM 17.74), a severe urban sky for astronomy.

Is Sioux Falls good for stargazing?

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

Is Sioux Falls good for astrophotography?

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

What can you observe from Sioux Falls?

Primary targets from Sioux Falls 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 Sioux Falls?

The closest meaningfully darker mapped site is Highland Township, South Dakota, about 37 km north north east of Sioux Falls, reaching Bortle 4.

When is the sky darkest in Sioux Falls?

The sky over Sioux Falls is darkest around January, December.

Is light pollution in Sioux Falls getting better or worse?

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

• Highland Township, South Dakota

  Direction

  NNE

  Distance (km)

  36.8

  SQM

  20.93

  Bortle

  4

• 2636, Iowa

  Direction

  ESE

  Distance (km)

  42.6

  SQM

  20.73

  Bortle

  5

• Dolton Township, South Dakota

  Direction

  WSW

  Distance (km)

  43.2

  SQM

  20.02

  Bortle

  6

• Middletown Township, Minnesota

  Direction

  E

  Distance (km)

  141.2

  SQM

  21.39

  Bortle

  3

• County Road 30, Minnesota

  Direction

  NE

  Distance (km)

  183.5

  SQM

  21.04

  Bortle

  4