Space Objects

Asteroids and comets passing Earth within a lunar-distance limit in the next or last N days: distance, speed, size range.

Asteroid diameter from absolute magnitude H and albedo (or a dark-to-bright range), plus optional impact energy in megatons.

Past and future Earth close approaches of one asteroid or comet by designation, for example Apophis in 2029.

Recorded fireball (bolide) events from US sensors: time, place, altitude, speed and impact energy in kilotons, newest first.

Is this asteroid on the JPL Sentry impact-risk list? Probability, Palermo and Torino levels, size and likeliest impact dates.

JPL Sentry impact-monitoring objects above a Palermo-scale threshold: probability, Torino level, size and impact years.

Torino scale levels explained, or the Palermo scale value from impact probability, energy in megatons and years until impact.

Orbital period from semi-major axis via Kepler's third law, with perihelion, aphelion and speeds when eccentricity is given.

Asteroid or comet by name or designation: orbit class, NEO/hazardous flags, size, orbit elements, MOID and discovery.

Convert a distance between km, miles, astronomical units and lunar distances, with light travel time.