Astronomy & references

Ten worlds, their measured astronomical settings, and the evidence behind each chapter. Numerical values retain the saved NASA snapshot; later papers are not silently substituted for its measurements.

Ten independently prompted illustrations depict six planetary surfaces and four explicitly invented moons, anchored to ten catalogued planets in nine host systems. Full-resolution originals live in World Images. Every scene has an image science companion, a registry assignment and a chapter. “Prehistoric” means an imagined world before recorded history; these are not reconstructions of discovered alien fossils.

Numerical properties are frozen from the NASA Exoplanet Archive composite snapshot retrieved 25 September 2026. Different parameters can come from different source papers and do not form a single self-consistent model. The companion pages retain source-specific errors, upper or lower limits and calculated-value provenance. Equilibrium temperature is not surface temperature; unknown is not zero.

Kepler-62 e and f have catalog mass upper limits, not those exact measured masses. Kepler-442 b and TOI-700 d have mass–radius-derived mass entries. HD 28185 b has a minimum mass and calculated radius. No scene uses those uncertain values as a measured gravity to certify giant animals. LHS 1140 b has measured central mass 5.6 Earth masses and radius 1.73 Earth radii: g/gEarth = 5.6/1.73² ≈ 1.87, a central estimate without uncertainty propagation.

For a spherical object of radius R at observer distance d, angular diameter is 2 asin(R/d). An invented Moon-sized body with R = 1,737 km gives approximately 4.98° at 40,000 km and 3.98° at 50,000 km. These distances illustrate a visual concept; they are not satellite detections, orbital-stability results or forecasts of tidal height. The Moon formed closer to Earth; the extreme early-Moon sky is not a reconstruction of Earth’s dinosaur era. The present recession rate must not be extrapolated unchanged through geological time.

The four satellite scenes assign images to their real parent planets: Kepler-16 b, Kepler-47 c, Kepler-1647 b and HD 28185 b. All satellite sizes, masses, orbits, atmospheres, histories and ecologies are invented. Their huge sky objects are the parent planets, not additional nearby confirmed worlds. Rings are invented only for the HD 28185 b scene. Gas-rich planets are never given ordinary exposed ground.

Binary systems support two real stellar sources, but sky position, apparent separation, phase and shadow geometry require an orbital model not supplied here. Catalog incident flux entries for binaries may not describe the time-varying combined irradiation; this book does not use them as complete climate budgets. Single-star nominal angular sizes use saved central stellar radii and orbital distances. The artwork is not a calibrated sky, and visual-review notes identify departures from prompt targets.

Each body plan was designed independently: an open body ring, a blade comb, many joined chambers, a deformable torus, an aquatic lattice, a mobile pleated fan, thermal bellows, an aerial chambered body, a radial strider and a perforated sheet. Proposed feeding, transport, sensing and locomotion mechanisms are fiction. No physiology, gravity, ecosystem, climate, lifting-gas budget or structural calculation proves that these giant forms could survive. Their colors and scale are creative choices.

The jacket reuses the opening scene with live typographic layout; it is not an eleventh world. The reader works offline, supports keyboard navigation, searchable contents, saved position, adjustable text, full-screen artwork with zoom, and printing of every chapter. Public copies use bounded WebP derivatives. This local build does not publish the site.