Meteorium vs Eclipse Simulator

Meteorium is an astronomy app that scientifically visualises the "dust trails" — the ribbons of comet dust that give rise to meteor showers. It shows 60,000 dust grains released by comet 109P/Swift-Tuttle, the parent of the Perseid meteor shower, over its eight perihelion returns from 1079 to 1992. Each grain is ejected from the comet's nucleus around perihelion and followed by full orbital integration including planetary gravity and solar radiation pressure, then rendered in 3D against NASA's all-sky star maps. The comet's position at the moment of ejection is anchored to the JPL Horizons ephemeris, which uses an orbit solution fitted to the observations of each historical apparition. Features: • 3D dust trails coloured by ejection year • Multiple viewpoints (ecliptic north/south, latitude sweep, Sun, ground, comet) plus a free view that tours the highlights every 10 s • Run time forward/backward at 10-10,000x to watch the trails evolve • Realistic Milky Way (NASA Deep Star Maps 2020), constellation lines and names, planets • Japanese / English Why do meteor showers return on the same dates every year? How does comet dust spread through the solar system? Meteorium shows you the three-dimensional structure and its evolution over time — and from the ground view you can simply enjoy the meteor shower itself. The app works fully offline, with no data collection and no ads. A Pro edition — theory computation for every shower, worldwide observation databases, ZHR outburst forecasts, dust-trail cross-sections, recording and image export — is in preparation.

Eclipse Simulator is an educational and investigative tool for finding unusual solar and lunar eclipses by combining an observing location, horizon conditions, and long-term Earth-rotation variation (ΔT). Its search catalog spans astronomical year -999 (1000 BCE) through 5000 CE. Study each event through maps, a ground-level view, and contact times. Key features • Search solar and lunar eclipses by date range, eclipse type, location, and other available criteria. • Narrow the search with an observing location, solar horizon conditions near sunrise or sunset, lunar moonrise or moonset, and ΔT. • View solar-eclipse center and limit lines, partial-eclipse regions, and lunar-eclipse visibility on Apple Maps. • Choose an observing location and play the changing alignment of the Sun, Moon, and shadow from the ground. • Inspect the contact times that exist for the event, including C1–C4 for solar eclipses and P1–P4/U1–U4 for lunar eclipses. • Compare the standard ΔT model with alternative scenarios to understand how uncertainty affects historical and future timing and paths. • View stars and constellation lines adjusted to the selected event time instead of showing today’s sky. • Share the selected event as CSV or JSON and the displayed screen as PNG or PDF. On iPhone, the app uses focused screen-by-screen navigation. On iPad, its wider layout keeps the catalog and event workspace within easier reach. If you grant location access, it is used only to set the observing point to your current location. You can also select a point on the map or enter coordinates. About time and accuracy Results are modeled values derived from the ephemeris, ΔT model, and Earth-orientation model recorded with the bundled data. The broad search catalog includes a low-precision analytical ephemeris, while the calculation provenance for a selected event is shown in the app and exports. Uncertainty remains in ΔT, future civil-time rules, polar motion, lunar-limb terrain, local terrain, and weather. Historical and future views use present-day Apple Maps and do not reconstruct borders or cities from the selected era. Lunar-eclipse color is schematic. Use the app for education, understanding astronomical geometry, and comparing model assumptions. Do not rely on it as a guaranteed value for observation planning, navigation, scientific conclusions, or safety-critical decisions.