Recent NEAs
σ > 10" Or
Phase < 1°
Low dV

Tool Descriptions


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.

Critical List Of Asteroids

Asteroids in need of observation due to large ephemeris uncertainty.

Asteroid Orbital Elements

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

Hierarchical Observing Protocol

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 in the process of being upgraded and as such is in beta status; some tools may experience bugs. If a bug is particularly important, please direct concerns to

Recent Updates

For the full history of updates see the updates page.