RESEARCH BASE

Search 3,721 documents across 34 fields — every claim tier-rated by evidence

3,721 Documents 34 Sections 43,625 Citations 34,852 Keywords Indexed 4 Evidence Tiers

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.

7 results for "limiting magnitude"

ZH_5_10 Verified Archaeoastronomy

ZH_5_10 — Naked-Eye Observational Limits: Precision, Techniques, and Ancient Achievement

For all but the last ~400 years of human history, every astronomical observation was made with the unaided eye. Understanding the limits and capabilities of naked-eye observation is therefore essential for evaluating anc

naked-eye observation visual acuity atmospheric refraction limiting magnitude angular resolution Tycho Brahe
ZH_1_15 Verified Archaeoastronomy

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

star catalog Hipparchus Ptolemy Almagest Ulugh Beg Tycho Brahe
ZF_3_12 Verified Oceanography

ZF_3_12 — Submarines, Submersibles, and the History of Ocean Exploration

The history of ocean exploration technology spans from the earliest diving bells (Alexander the Great's legendary glass barrel, ~332 BCE; Halley's practical diving bell, 1690) to full-ocean-depth human-occupied vehicles

submarine submersible bathysphere bathyscaphe Trieste Alvin
Z_3_07 Verified Molecular Biology

Z_3_07 — Gene Drive Technology

Gene drives are genetic systems that bias their own inheritance to spread through a population at rates exceeding normal Mendelian expectations (~50% → ~99% transmission). Natural selfish genetic elements (transposons, m

gene drive CRISPR gene drive selfish genetic element meiotic drive super-Mendelian inheritance Anopheles
K_5_07 Verified Consciousness

K_5_07 — Psychophysics: Measuring the Relationship Between Mind and World

Psychophysics — literally "the physics of the soul/mind" — is the scientific study of the quantitative relationship between physical stimuli and the sensations and perceptions they produce. Founded by Gustav Theodor Fech

psychophysics Fechner Weber Stevens signal detection theory threshold
ZG_1_18 Credible Linguistics & Communication

ZG_1_18 — Sound Symbolism and Phonosemantics

Sound symbolism — the non-arbitrary association between speech sounds and meaning — challenges the foundational Saussurean principle that the relationship between a word's form and its meaning is entirely arbitrary (Ferd

sound-symbolism phonosemantics bouba-kiki ideophones onomatopoeia iconic-language
Q_2_11 Verified Cosmology & Physics

Q_2_11 — Stellar Populations, Metallicity, and Generations

Stars preserve the chemical fingerprint of the gas from which they formed, making them archaeological records of the universe's chemical history. Walter Baade (1944) recognized two distinct stellar populations: Populatio

stellar populations Population I Population II Population III metallicity metal-poor stars