Total Known:
Total Plotted:
X-axis: Semi-Major Axis
Y-axis: Inclination
Asteroid populations are based on computed dynamical types.
Advanced Query
Plot Settings

Observing Tools

Interactive table of observable NEOs

Asteroid and observatory-specific ephemeris generator.

Build finder chart for a given asteroid and time.

Return orbital and physical properties for a given asteroid.

Observability chart for asteroids and observatory.

Asteroids whose orbits are near one or more of the major planets.

Pre-defined lists of asteroids observable tonight.

Access to, and information about, the astorb orbital elements database.

Generate asteroid observing priority list given a set of criteria.

Lowell Observatory offers these tools to assist with asteroid observation planning and to facilitate data mining across multiple surveys. Orbital solutions are calculated in-house based on Minor Planet Center observations.

This website is routinely updated; some tools may experience bugs. If a bug is particularly important, please direct concerns to

For more details see the astorb citation

Recent Updates

For the full history of updates see the updates page.
Date Update