NEOWS (NASA Near Earth Object Web Service)

This document details how to use the NASA Near Earth Object Web Service (NEOWS) API to retrieve information about near-Earth objects.

Base Endpoint

To get detailed information about a specific NEO (Near Earth Object), use the following endpoint:

http://api.nasa.gov/neo/rest/v1/neo/{neo_id}?api_key=YOUR_API_KEY

This endpoint returns the specified object's physical and orbital properties, as well as its close-approach data.

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1. General NEO Information

This section contains the object's identifiers and general characteristics.

Field	Type	Description
id	string	The internal identifier for the NEO in the JPL database.
neo_reference_id	string	A unique reference identifier for the NEO.
name	string	The official name of the NEO.
designation	string	A provisional or alternative designation.
nasa_jpl_url	string	The URL to the JPL Small-Body Database for this NEO.
absolute_magnitude_h	float	The absolute magnitude (H), used to estimate the object's size.
is_potentially_hazardous_asteroid	bool	Indicates whether the NEO is considered potentially hazardous.

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2. Estimated Diameter (estimated_diameter)

This object contains the estimated diameter range of the NEO in different metric and imperial units.

Sub-field	Type	Description
kilometers.estimated_diameter_min	float	Minimum estimated diameter in kilometers.
kilometers.estimated_diameter_max	float	Maximum estimated diameter in kilometers.
meters.estimated_diameter_min/max	float	Estimated diameter in meters.
miles.estimated_diameter_min/max	float	Estimated diameter in miles.
feet.estimated_diameter_min/max	float	Estimated diameter in feet.

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3. Close Approach Data (close_approach_data)

A list containing all recorded close approaches of the NEO to other planetary bodies.

Field	Type	Description
close_approach_date	string	The date of the close approach in YYYY-MM-DD format.
close_approach_date_full	string	The full date and time of the close approach.
epoch_date_close_approach	int	The date of the event in epoch format (milliseconds since 1970).
relative_velocity	object	Relative velocity to the body in km/s, km/h, and mph.
miss_distance	object	Minimum distance to the body in astronomical units, kilometers, miles, and lunar distances.
orbiting_body	string	The main body around which the close approach occurs (e.g., "Earth").

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4. Orbital Data (orbital_data)

This object contains all the orbital parameters that define the NEO's trajectory.

Field	Type	Description
orbit_id	string	A unique identifier for the orbital solution.
orbit_determination_date	string	The date the orbit was determined.
first_observation_date	string	The date of the first observation used for the calculation.
last_observation_date	string	The date of the last observation used.
data_arc_in_days	int	The duration of the observation arc in days.
observations_used	int	The total number of observations used.
orbit_uncertainty	string	The orbit uncertainty code (where 0 is very certain).
minimum_orbit_intersection	float	The Minimum Orbit Intersection Distance (MOID) with Earth in astronomical units (AU).
jupiter_tisserand_invariant	float	Tisserand's invariant with respect to Jupiter, used for classification.
epoch_osculation	float	The epoch of osculation in Julian Days (JD).
eccentricity (e)	float	The eccentricity of the orbit.
semi_major_axis (a)	float	The semi-major axis in astronomical units (AU).
inclination (i)	float	The orbital inclination in degrees.
ascending_node_longitude (Ω)	float	The longitude of the ascending node in degrees.
perihelion_distance (q)	float	The distance to the perihelion in astronomical units (AU).
perihelion_argument (w)	float	The argument of perihelion in degrees.
aphelion_distance (Q)	float	The distance to the aphelion in astronomical units (AU).
perihelion_time (tp)	float	The epoch of the perihelion in Julian Days (JD).
mean_anomaly (M)	float	The mean anomaly in degrees.
mean_motion (n)	float	The mean motion in degrees per day.
orbital_period	float	The orbital period in days.
equinox	string	The reference epoch for the coordinates (usually J2000).
orbit_class	object	The orbit class with a description and orbital range.
is_sentry_object	bool	Indicates if the object is being monitored by the Sentry program (future impact risk).