Overlooking the Mississippi River bluffs in northeastern Iowa, Effigy Mounds National Monument preserves over 200 prehistoric earthworks — 31 shaped as bears and birds with wingspans exceeding 60 meters. Built by Woodland cultures between 450 BCE and 1300 CE, the Great Bear Mound stretches 42 meters long and rises over a meter high. The mounds' placement corresponds to solstice and equinox sightlines along the river valley. Sacred to the Ho-Chunk Nation, who identify them as burial sites of ancestors and spirit beings. At 47.06° Giza bearing, the site lies on the same great-circle arc as other major effigy earthworks of the upper Mississippi, forming a ceremonial corridor along the continent's central waterway.
WikipediaStellar Alignments (56 stars)
| Star ▴ | Rise Az ▴ | Rise Δ ▴ | Set Az ▴ | Set Δ ▴ | Tradition ▴ |
|---|---|---|---|---|---|
| Alpheratz | 48.3° | 1.2° | 311.7° | 95.3° | |
| Scheat | 49.9° | 2.8° | 310.1° | 96.9° | |
| Pollux | 50.0° | 2.9° | 310.1° | 97.0° | |
| Castor | 43.7° | 3.4° | 316.3° | 90.7° | |
| Bharani (41 Arietis) | 51.2° | 4.1° | 308.8° | 98.2° | |
| Alphecca | 52.0° | 4.9° | 308.0° | 99.0° | |
| Pleiades (Alcyone) | 56.0° | 8.9° | 304.0° | 103.1° | |
| Hamal | 57.0° | 9.9° | 303.0° | 104.0° | |
| Kornephoros | 59.9° | 12.8° | 300.1° | 107.0° | |
| Pushya (Gamma Cancri) | 59.9° | 12.9° | 300.1° | 107.0° | |
| Vega | 30.9° | 16.1° | 329.1° | 78.0° | |
| Arcturus | 63.3° | 16.2° | 296.7° | 110.3° | |
| Aldebaran | 67.1° | 20.0° | 292.9° | 114.2° | |
| Alhena | 67.3° | 20.2° | 292.7° | 114.3° | |
| Algol | 26.1° | 20.9° | 333.9° | 73.2° | |
| Markab | 69.0° | 21.9° | 291.1° | 116.0° | |
| Denebola | 69.8° | 22.8° | 290.1° | 116.9° | |
| Rasalgethi | 70.1° | 23.1° | 289.9° | 117.2° | |
| Rasalhague | 72.7° | 25.6° | 287.3° | 119.7° | |
| Regulus | 73.5° | 26.4° | 286.5° | 120.6° | |
| Vindemiatrix | 74.9° | 27.9° | 285.1° | 122.0° | |
| Enif | 76.4° | 29.4° | 283.6° | 123.5° | |
| Altair | 77.8° | 30.8° | 282.2° | 124.9° | |
| Betelgeuse | 79.8° | 32.8° | 280.2° | 126.9° | |
| Deneb | 13.3° | 33.7° | 346.6° | 60.4° | |
| Unukalhai | 81.2° | 34.1° | 278.8° | 128.2° | |
| Bellatrix | 81.3° | 34.2° | 278.7° | 128.3° | |
| Procyon | 82.8° | 35.8° | 277.2° | 129.9° | |
| Capella | 9.9° | 37.1° | 350.1° | 57.0° | |
| Mintaka | 90.4° | 43.4° | 269.6° | 137.5° | |
| Sadalmelik | 90.4° | 43.4° | 269.6° | 137.5° | |
| Orion Belt (Alnilam) | 91.6° | 44.6° | 268.4° | 138.7° | |
| Alnitak | 92.7° | 45.6° | 267.3° | 139.7° | |
| Sadalsuud | 97.6° | 50.6° | 262.4° | 144.7° | |
| Rigel | 101.3° | 54.2° | 258.7° | 148.3° | |
| Alphard | 101.9° | 54.8° | 258.1° | 148.9° | |
| Zubeneschamali | 102.9° | 55.8° | 257.1° | 149.9° | |
| Saiph | 103.3° | 56.2° | 256.7° | 150.3° | |
| Spica | 105.4° | 58.3° | 254.6° | 152.4° | |
| Sabik | 111.8° | 64.7° | 248.2° | 158.8° | |
| Zubenelgenubi | 112.2° | 65.2° | 247.8° | 159.3° | |
| Sirius | 113.2° | 66.1° | 246.8° | 160.3° | |
| Murzim | 115.0° | 67.9° | 245.0° | 162.0° | |
| Diphda | 115.0° | 68.0° | 245.0° | 162.1° | |
| Nunki | 127.3° | 80.3° | 232.7° | 174.4° | |
| Wezen | 127.5° | 80.4° | 232.5° | 174.6° | |
| Antares | 127.5° | 80.5° | 232.4° | 174.6° | |
| Adhara | 131.6° | 84.5° | 228.4° | 178.6° | |
| Fomalhaut | 132.6° | 85.5° | 227.4° | 179.7° | |
| Phact | 140.1° | 93.0° | 219.9° | 172.8° | |
| Kaus Australis | 140.6° | 93.6° | 219.4° | 172.3° | |
| Menkent | 144.3° | 97.2° | 215.7° | 168.7° | |
| Shaula | 145.7° | 98.6° | 214.3° | 167.3° | |
| Naos | 151.7° | 104.6° | 208.3° | 161.3° | |
| Ankaa | 157.2° | 110.1° | 202.8° | 155.8° | |
| Suhail | 160.3° | 113.2° | 199.7° | 152.7° |
Convergence Events (3)
48.3°
Alpheratz Rise
Chinese (Wall/Bi mansion), Arabic, Hindu
Δ 1.2°
49.9°
Scheat Rise
Hindu (Purva Bhadrapada), Arabic, Chinese, Persian
Δ 2.8°
50.0°
Pollux Rise
Greek (Dioscuri), Hindu (Punarvasu), Chinese, Arabic
Δ 2.9°
Related Sites — Ley Line — Earth Grid