RESEARCH BASE
Search 3,721 documents across 34 fields — every claim tier-rated by evidence
3,633 are the core, quality-scored corpus (34 lettered sections — see How We Work); the remaining 88 are cross-corpus synthesis documents (68 InterDocs, 12 Connections, 8 Theories) also indexed here.
563 results for "ice ages" — page 9 of 29
ZH_3_04 — Chaco Canyon: Solar Markers and Pueblo Astronomy
Chaco Canyon (northwestern New Mexico) was the center of Ancestral Puebloan (formerly called Anasazi) civilization from approximately 850–1150 CE, featuring monumental Great Houses containing hundreds of rooms, extensive
ZH_3_10 — North American Mound Builders and Celestial Alignments
The mound-building cultures of eastern North America — spanning from Poverty Point (~1700 BCE) through the Adena (~800–100 BCE), Hopewell (~100 BCE–500 CE), Fort Ancient (~1000–1650 CE), and Mississippian (~800–1500 CE)
ZH_3_15 — Norse Astronomy: Sunstones, Aurvandil's Toe, and Viking Celestial Navigation
The Norse/Viking world (c. 800–1100 CE) developed a distinctive astronomical culture shaped by extreme northern latitudes — long summer days with no true darkness, short winter days with extended night, the aurora boreal
ZH_3_09 — Solar Geometry in Pueblo Architecture: Mesa Verde, Hovenweep
The Ancestral Puebloan peoples (formerly termed "Anasazi") of the American Southwest incorporated sophisticated solar geometry into their architecture, settlement planning, and ceremonial life across a vast region center
ZH_3_21 — Chankillo Solar Observatory
Chankillo (also spelled Chanquillo) — a monumental archaeological complex in the Casma-Sechín Valley of coastal Peru, approximately 380 km north of Lima — contains the oldest known solar observatory in the Americas and o
ZH_5_24 — Zoroastrian Astral Cosmology and Fire-Temple Astronomy
Zoroastrianism — one of the world's oldest continuously practiced religions, founded by Zarathustra (dates debated: c. 1500–600 BCE) in Greater Iran — embedded astronomical observation deeply into its cosmology, calendar
ZH_5_21 — Precession of the Equinoxes: The Great Year and Ancient Awareness
The precession of the equinoxes — the slow westward drift of the vernal equinox point along the ecliptic, completing a full cycle in approximately 25,772 years (the "Great Year" or "Platonic Year") — is the longest astro
ZH_5_06 — Horizon Astronomy: Skyline Observations, Foresights, and Horizonal Calendars
Horizon astronomy — the practice of observing where celestial bodies rise and set along the natural skyline — is the most ancient, most widespread, and most practical form of astronomical observation. Unlike meridian tra
ZH_5_07 — Light and Shadow Hierophanies: Temple Sun Daggers and Solar Inserts
A hierophany — a manifestation of the sacred — is realized in some of the world's most famous ancient structures through the precise interplay of light and shadow. On specific calendar dates — typically solstices, equino
ZH_5_04 — Precession of the Equinoxes: Hipparchus, Axial Wobble, and the Great Year
The precession of the equinoxes — the slow, continuous westward shift of the equinoctial points (where the ecliptic crosses the celestial equator) along the ecliptic — is one of the most consequential astronomical phenom
ZH_2_17 — Islamic Golden Age Astronomy: Observation, Innovation, and the Preservation of Knowledge
Islamic astronomy — the astronomical tradition developed in the Islamic world from the 8th through the 15th centuries CE — represents one of the most productive and consequential scientific enterprises in human history,
ZH_2_06 — Astronomy in the Rig Veda and Early Indian Texts
The Rig Veda — the oldest of the four Vedas and among the oldest religious texts still in continuous use (~1500–1200 BCE, though dating is debated) — contains hymns, references, and cosmological imagery that reflect the
ZH_2_18 — Angkor Wat Astronomical Alignments
Angkor Wat — the vast Hindu-Buddhist temple complex in Siem Reap, Cambodia, built by King Suryavarman II between approximately 1113 and 1150 CE — is not only the largest religious monument on Earth (covering 162.6 hectar
ZH_2_08 — Astronomical Dating of Ancient Texts and Events
Astronomical dating — the use of recorded or described celestial events (eclipses, planetary conjunctions, solstice positions, heliacal risings, and precessional indicators) to fix the absolute dates of ancient texts and
ZH_2_19 — Petra Astronomical Alignments
Petra — the Nabataean capital carved into sandstone cliffs in southern Jordan, active from approximately 400 BCE to 106 CE — contains a sophisticated network of astronomical alignments integrated into its monumental arch
ZH_2_15 — Astronomical Time: Defining Days, Years, Hours, and the Second
The measurement and definition of time is humanity's oldest astronomical enterprise — and one that has undergone a radical transformation from celestial observation to atomic precision. The fundamental units derive from
ZH_1_15 — Star Catalogs: From Hipparchus to Hipparcos and the Tycho Catalog
A star catalog — a systematic list of stars with their positions, magnitudes, and sometimes colors, proper motions, and spectral types — is the foundational document of observational astronomy. The compilation of ever mo
ZH_1_01 — Archaeoastronomy: Discipline, Debates, and Cultural Astronomy
Archaeoastronomy is the interdisciplinary study of how past cultures understood, used, and integrated celestial phenomena — the motions of the sun, moon, planets, and stars — into their architecture, ritual practices, ag
ZH_1_04 — Nebra Sky Disk: Bronze Age Star Map Analysis
The Nebra sky disk (Himmelsscheibe von Nebra) is a bronze disk approximately 30 cm in diameter, decorated with gold-leaf appliqué representing the sun (or full moon), a crescent moon, stars (including a cluster interpret
ZH_1_06 — Zodiac Origins: Babylonian MUL.APIN to Greek Transmission
The zodiac — the division of the ecliptic (the apparent annual path of the Sun against the background stars) into 12 equal 30° segments, each named after a constellation — is a Babylonian invention that became the founda
BROWSE BY SECTION — 3,721 documents across 34 fields