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Asteroid Near-Earth

2018 AD4

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(2018 AD4)

Where is it now

Distance from Sun
0.941 AU
True anomaly
105.95°
Distance from Earth
0.529 AU
As of
21 October 2026

Two-body Kepler propagation — accurate to ~0.1% for major planets over decades, less so for highly-perturbed bodies. Use JPL Horizons for high precision.

Sun Earth — 0.995 AU from the Sun Earth 2018 AD4 — 0.941 AU from the Sun 2018 AD4
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2018 AD4 is 0.529 AU from Earth today (4.4 light-minutes).

In the sky

Right ascension
09h 10m 43s
Declination
-04° 30′ 32″
Constellation
Hydra
Distance from Earth
0.53 AU
Elongation from the Sun
68.87° — well clear of the Sun

Visible from both hemispheres.

From your location

See how high it is right now, whether it is up after civil twilight, and when it rises and sets where you are.

How do I find my coordinates?

Google Maps on a computer

  1. Right-click the spot where you'll be observing.
  2. The first line of the menu is the coordinates, e.g. 51.50722, -0.12758 — click it and they're copied.
  3. Paste them above.

Google Maps on a phone

  1. Press and hold the spot to drop a pin.
  2. The coordinates appear in the search bar (or on the pin's card) — tap to copy, then paste above.

A full Google Maps link works too, but the short maps.app.goo.gl share links don't carry coordinates — copy the numbers instead. We round to about a kilometre; that's all the sky calculation needs.

Know your what3words address? Paste it, e.g. ///filled.count.soap. This is optional — the three words are sent to what3words to convert them, and we don't store the address or the result.

Your location stays in your browser and is sent only for this calculation. Using a what3words address is optional; if you do, the three words go to what3words to be converted and we don't record them. Set a location first, then you can save an email alert for this object. See our privacy policy.

Two-body approximation, good to about a degree for the planets — enough to find the constellation and know whether it is up.

Orbital elements

Semi-major axis
0.929 AU
Eccentricity
0.2187
Inclination
13.57°
Orbital period
327 days
Perihelion
0.726 AU
Aphelion
1.132 AU
Longitude of ascending node
112.15°
Argument of periapsis
199.19°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 44.6 LD
0.1146 AU
Tisserand (Jupiter)
6.403

Orbit quality

Orbit very well determined (uncertainty code 1).

Observations used
83
Data arc
8.02 years
First observed
14 December 2017
Last observed
22 December 2025
Residual RMS
0.46 ″
Solution · Otto Matic
22 December 2025

Visual & observation

Absolute magnitude (H)
22.72

Discovery & classification

Aten Near-Earth Object

Close approaches 52 on record

Flyby geometry
Ecliptic flyby of 2018 AD4 at 2035-01-07 16:06 UTC Top-down view of the ecliptic, Earth at the centre, for the 2035-01-07 16:06 UTC close approach of 2018 AD4. Catalogue miss distance 49.3 LD · 1.9 × 10⁷ km. The curve is the geocentric path from 2035-01-04 to 2035-01-10, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 49.3 LD · 1.9 × 10⁷ km 2035-01-07 16:06 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2035-01-07 16:06 UTC close approach of 2018 AD4. Catalogue miss distance 49.3 LD · 1.9 × 10⁷ km. The curve is the geocentric path from 2035-01-04 to 2035-01-10, with a mark at UTC midnights and an arrow for the direction of motion. The circle is the Moon’s mean orbit; the Moon is plotted at closest approach. A ray shows the Sun’s direction. The labelled distance is the full separation. The drawn radius is the part that lies in the ecliptic plane. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate.

JPL Horizons

When (UTC) Body Distance Lunar distances Relative speed
2034-08-17 16:56:00 Venus 0.0905 AU 35.2 LD 10 km/s
2035-01-07 16:06:00 Earth 0.1268 AU 49.3 LD 8.4 km/s
2044-06-18 20:26:00 Venus 0.1115 AU 43.4 LD 10.8 km/s
2052-01-12 14:24:00 Earth 0.1361 AU 53.0 LD 8.4 km/s
2059-12-18 04:11:00 Earth 0.1663 AU 64.7 LD 10.9 km/s
2069-01-20 13:30:00 Earth 0.1549 AU 60.3 LD 8.4 km/s
2072-03-27 23:28:00 Venus 0.1314 AU 51.1 LD 10.4 km/s
2076-12-19 19:40:00 Earth 0.1355 AU 52.7 LD 9.8 km/s
2082-01-26 14:39:00 Venus 0.1061 AU 41.3 LD 9.5 km/s
2086-01-24 05:21:00 Earth 0.1632 AU 63.5 LD 8.4 km/s

Next ten from today. 1 lunar distance = 384,400 km. Source: JPL close-approach data.

Sources