Hidden Springs State Forest

How dark the sky is at Hidden Springs: Bortle Class 4, rural and suburban transition

The zenith sky here reads 21.65 magnitudes per square arcsecond. That is about 1.4 times the brightness of a pristine natural sky (22.0), the extra coming from artificial light scattered in the air.

Sky brightness and class come from the World Atlas of Artificial Night Sky Brightness (Falchi et al. 2016, CC BY-NC 4.0), with natural skyglow added. On the night, haze, smoke, humidity and the Moon set the real limit.

What's up from Hidden Springs by season

At latitude 39.3°N, the north celestial pole stands 39° above the horizon, close to Polaris. Every star north of declination -51° rises at some time of year. The Milky Way core in Sagittarius climbs to 22° above the southern horizon. These are the constellations well placed, 35° or more above the horizon, at about 10 pm in the middle of each season, brightest first.

Showpieces from Hidden Springs through the year

At about 10 pm on the 15th of each month; a dash means the sight is below 25° then.

Never set from Hidden Springs

• Camelopardalis
• Cassiopeia
• Cepheus
• Draco
• Ursa Major
• Ursa Minor

Only skim the southern horizon from Hidden Springs

• Centaurus
• Grus
• Lupus
• Phoenix
• Telescopium
• Vela

Never rise from Hidden Springs

• Apus
• Ara
• Carina
• Chamaeleon
• Circinus
• Crux
• Dorado
• Horologium
• Hydrus
• Indus
• Mensa
• Musca
• Norma
• Octans
• Pavo
• Pictor
• Reticulum
• Triangulum Australe
• Tucana
• Volans

Where to set up at Hidden Springs

The coordinates on this page point to Forest center, at 200 m (660 ft): 39.319°N, 88.690°W.

Map data © OpenStreetMap contributors. Open the larger map · Directions. Arrive before dark, park facing away from other observers, and use red light only.

Hidden Springs among the dark sky places of Illinois

Each dot is a dark sky place, colored by Bortle class; select one for its page. Diamonds are star parties. See Illinois dark sky places for the full list, darkest first.

Camping and lodging at Hidden Springs

The nearest town with motels or inns is Shelbyville, IL. Check the official site for campgrounds and overnight rules; many parks close their gates at night, so ask about after-dark access.

Dark sky places nearest Hidden Springs

Star parties near Hidden Springs

Planning a trip? Astrotourism in Illinois puts the dark sky places, observatories, clubs, star parties, planetariums and science centers of the state on one map, with the best night out worked out.

Observatories and astronomy clubs near Hidden Springs

Observatories within 100 km

• University of Illinois ObservatoryUrbana, Illinois, 97 km (60 mi), open to the public
• Henry Barber Research ObservatorySpringfield, Illinois, 98 km (61 mi), research observatory

Nearest astronomy clubs

• Champaign-Urbana Astronomical SocietyTolono, Illinois, 83 km (51 mi). Meets 2nd Thursday monthly (see cuas.org for venue)
• Astronomical Society at University of IllinoisUrbana, Illinois, 96 km (60 mi). Meets Bi-weekly during semester, University of Illinois campus
• Sangamon Astronomical SocietySpringfield, Illinois, 102 km (63 mi)
• River Bend Astronomy ClubHighland, Illinois, 106 km (66 mi). Meets Meetings at Salem UCC, 1117 W North St
• Rose-Hulman Astronomical SocietyTerre Haute, Indiana, 116 km (72 mi)

See observatories and astronomy clubs in Illinois. Local clubs often hold their star parties at dark sky places like this one.

Hidden Springs record

From the site's dark sky places dataset (parks_q426). The sky by season is computed from the coordinates.