SpaceAtlas Space Object Data
NASA JPL SBDB · 2019 UD4

2019 UD4

2019 UD4 is an Amor-type near-Earth asteroid that approaches Earth from beyond our orbit without crossing it, orbiting the Sun at 1.568 AU once every 1.96 yr.

Amor Observations: 365
Orbital Period · P
1.96 yr
v(q)
34.2 km/s
v(Q)
16.5 km/s
Diameter · ≈
0.08 km
TJ
4.35
Eccentricity · e
0.3477

Orbit and dynamics

Between its closest point (1.023 AU) and its farthest (2.113 AU), the heliocentric distance changes by 1.09 AU over every revolution.

One full revolution takes 1.96 yr (717 days), computed from the semi-major axis of 1.568 AU.

An eccentricity of 0.348 makes the orbit moderately elongated.

Its inclination of 3.34° keeps it close to the plane of the ecliptic.

By the vis-viva equation its orbital speed rises to 34.2 km/s at perihelion and falls to 16.5 km/s at aphelion.

Its perihelion lies just outside Earth's orbit, which is why it is classed as Earth-approaching rather than Earth-crossing.

Size and surface

No direct size measurement is available; from an absolute magnitude of H = 23.17 and an assumed geometric albedo of 0.14, the diameter works out to roughly 0.08 km.

Observation record and orbit quality

Astrometry from 365 individual observations underpins this orbit; the fit leaves an RMS residual of 0.4006 arcseconds.

Condition code U = 0 means the orbit is very well determined, leaving only a small uncertainty in the future ephemeris.

About these computed values

Orbital periods, perihelion and aphelion speeds, and diameter estimates on this page are computed by SpaceAtlas from the JPL SBDB orbital elements. They are derived quantities, not values copied from the source catalogue.

Orbital Parameters

Semi-Major Axis
1.568 AU
Eccentricity
0.3477
Perihelion
1.023 AU
Aphelion
2.113194 AU
Inclination
3.34°
Orbital Period
— yr
Epoch
2461200.5
Mean Anomaly
149.97°

Orbit diagram

The Sun sits at the focus (orange). Earth's orbit is the grey circle at 1 AU. The red dot marks the object's position at the catalog epoch.

3D orbit (interactive)

Drag to rotate; scroll or pinch to zoom. The Sun is at the focus (orange), Earth's orbit is the grey ring at 1 AU, and the red dot marks the object's current position.

Close approaches

Predicted close approaches to Earth, from NASA's Center for Near-Earth Object Studies (CNEOS).

Date (UTC)Miss distanceVelocity
2072-Oct-11 23:41 0.123183 AU
18427908 km
7.88 km/s
2074-Aug-17 18:32 0.048395 AU
7239827 km
6.07 km/s

Distances in astronomical units (AU) and kilometres. Source: NASA/JPL CNEOS Close Approach Data API.

Physical Parameters

Diameter
— km
Albedo
—
Density
— g/cm³
Rotation Period
— h
Absolute Magnitude
23.17

Orbit Quality

RMS
0.40056
Condition
0
Orbit ID
—
Data source: NASA JPL Small-Body Database · NASA CNEOS. Orbital periods, perihelion and aphelion speeds, and diameter estimates on this page are computed by SpaceAtlas from the JPL SBDB orbital elements. They are derived quantities, not values copied from the source catalogue.

Keep exploring

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