Built approximately 3200 BCE — older than Stonehenge by 1,000 years and the Great Pyramid by 600 years — this 85-meter passage tomb in Ireland's Boyne Valley is one of the most important megalithic structures in Europe. On the winter solstice, sunlight enters through a precisely engineered roof box above the entrance and penetrates 19 meters down the passage to illuminate the inner chamber for exactly 17 minutes. The inner chamber's acoustic resonance frequency is 110 Hz — the same frequency measured in Malta's Hal Saflieni Hypogeum, suggesting deliberate acoustic engineering across Neolithic cultures. The entrance kerbstone bears triple-spiral carvings that have become Ireland's most recognized archaeological symbol.
WikipediaStellar Alignments (89 stars)
| Star ▴ | Rise Az ▴ | Rise Δ ▴ | Set Az ▴ | Set Δ ▴ | Tradition ▴ |
|---|---|---|---|---|---|
| Pleiades (Alcyone) | 91.8° | — | 268.2° | — | |
| Orion's Belt (Alnilam) | 121.6° | — | 238.4° | — | |
| Sirius | 131.6° | — | 228.4° | — | |
| Thuban | — | — | — | — | |
| Vega | — | — | — | — | |
| Regulus | 47.7° | — | 312.3° | — | |
| Aldebaran | 99.8° | — | 260.2° | — | |
| Antares | 95.3° | — | 264.6° | — | |
| Fomalhaut | — | — | — | — | |
| Arcturus | — | — | — | — | |
| Galactic Center (Sgr A*) | 108.6° | — | 251.4° | — | |
| Galactic Anti-Center | 71.5° | — | 288.5° | — | |
| Deneb | — | — | — | — | |
| Capella | 44.0° | — | 316.0° | — | |
| Castor | 46.6° | — | 313.4° | — | |
| Pollux | 50.9° | — | 309.1° | — | |
| Procyon | 86.0° | — | 274.0° | — | |
| Betelgeuse | 104.2° | — | 255.8° | — | |
| Rigel | 139.1° | — | 220.9° | — | |
| Bellatrix | 110.5° | — | 249.5° | — | |
| Achernar | — | — | — | — | |
| Acrux | — | — | — | — | |
| Mimosa | 159.4° | — | 200.6° | — | |
| Altair | 72.0° | — | 288.0° | — | |
| Kochab | — | — | — | — | |
| Dubhe | — | — | — | — | |
| Alkaid | — | — | — | — | |
| Mizar | — | — | — | — | |
| Hamal | 95.8° | — | 264.2° | — | |
| Zubenelgenubi | 71.4° | — | 288.6° | — | |
| Alnitak | 122.1° | — | 237.9° | — | |
| Mintaka | 120.8° | — | 239.2° | — | |
| Saiph | 135.1° | — | 224.9° | — | |
| Peacock | — | — | — | — | |
| Miaplacidus | — | — | — | — | |
| Rigil Kentaurus | 165.8° | — | 194.2° | — | |
| Hadar | 157.7° | — | 202.3° | — | |
| Gacrux | 151.3° | — | 208.7° | — | |
| Naos | 175.0° | — | 185.0° | — | |
| Suhail | 154.9° | — | 205.1° | — | |
| Avior | — | — | — | — | |
| Atria | — | — | — | — | |
| Regor | — | — | — | — | |
| Alsephina | — | — | — | — | |
| Shaula | 120.5° | — | 239.5° | — | |
| Ankaa | — | — | — | — | |
| Menkent | 104.5° | — | 255.6° | — | |
| Alpheratz | 80.4° | — | 279.6° | — | |
| Eltanin | — | — | — | — | |
| Kornephoros | — | — | — | — | |
| Rasalhague | 34.9° | — | 325.1° | — | |
| Denebola | 9.5° | — | 350.5° | — | |
| Alhena | 83.0° | — | 277.0° | — | |
| Alphard | 89.5° | — | 270.5° | — | |
| Bharani | 100.3° | — | 259.7° | — | |
| Pushya | 55.2° | — | 304.8° | — | |
| Adhara | 161.7° | — | 198.3° | — | |
| Wezen | 150.1° | — | 209.9° | — | |
| Navi | 17.0° | — | 343.0° | — | |
| Schedar | 29.9° | — | 330.1° | — | |
| Nunki | 115.3° | — | 244.7° | — | |
| Canopus | — | — | — | — | |
| Kaus Australis | 123.3° | — | 236.7° | — | |
| Sabik | 82.8° | — | 277.2° | — | |
| Scheat | 75.6° | — | 284.4° | — | |
| Enif | 91.7° | — | 268.4° | — | |
| Diphda | — | — | — | — | |
| Alphecca | — | — | — | — | |
| Rasalgethi | 25.7° | — | 334.3° | — | |
| Spica | 63.4° | — | 296.6° | — | |
| Zubeneschamali | 60.8° | — | 299.2° | — | |
| Unukalhai | 28.8° | — | 331.2° | — | |
| Murzim | 144.0° | — | 216.0° | — | |
| Phact | — | — | — | — | |
| Mirfak | 47.5° | — | 312.5° | — | |
| Vindemiatrix | — | — | — | — | |
| Markab | 96.0° | — | 264.0° | — | |
| Algol | 65.2° | — | 294.8° | — | |
| Sadalmelik | 111.4° | — | 248.6° | — | |
| Sadalsuud | 113.3° | — | 246.7° | — | |
| Sun (Summer Solstice) | 47.8° | — | 312.2° | — | |
| Sun (Winter Solstice) | 132.2° | — | 227.8° | — | |
| Sun (Equinox) | 90.0° | — | 270.0° | — | |
| Sun (Northern Cross-Quarter) | 61.3° | — | 298.7° | — | |
| Sun (Southern Cross-Quarter) | 118.7° | — | 241.3° | — | |
| Moon (N Major Standstill) | 35.8° | — | 324.3° | — | |
| Moon (S Major Standstill) | 144.3° | — | 215.8° | — | |
| Moon (N Minor Standstill) | 57.2° | — | 302.8° | — | |
| Moon (S Minor Standstill) | 122.8° | — | 237.2° | — |
Convergence Events (2)
117.3°
Sabik Rise
Hindu (near Anuradha), Arabic, Babylonian
Δ 1.3°
117.8°
Zubenelgenubi Rise
Arabic (southern claw), Hindu, Babylonian
Δ 1.9°
Reference Bearings (20 landmarks)
| Landmark | Bearing | Distance |
|---|---|---|
| giza | 115.94° | 4,003 km |
| angkor wat | 65.80° | 10,092 km |
| nazca | 244.16° | 9,978 km |
| teotihuacan | 283.79° | 8,407 km |
| stonehenge | 129.73° | 421 km |
| gobekli tepe | 99.26° | 3,899 km |
| machu picchu | 243.02° | 9,687 km |
| easter island | 262.77° | 13,231 km |
| cahokia | 291.11° | 6,259 km |
| sedona | 302.94° | 7,847 km |
| mecca | 114.17° | 5,286 km |
| jerusalem | 109.47° | 4,098 km |
| vatican | 125.45° | 1,917 km |
| lhasa | 65.89° | 7,860 km |
| kailash | 71.95° | 7,137 km |
| uluru | 65.08° | 15,311 km |
| tiwanaku | 238.04° | 9,784 km |
| chaco canyon | 301.12° | 7,531 km |
| mt shasta | 314.08° | 7,810 km |
| levis stadium | 311.54° | 8,153 km |
Related Sites — Solar Alignment