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Asteroid Near-Earth

2017 OU18

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(2017 OU18)

Where is it now

Distance from Sun
0.875 AU
True anomaly
239.65°
Distance from Earth
0.572 AU
As of
19 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 — 0.996 AU from the Sun Earth 2017 OU18 — 0.875 AU from the Sun 2017 OU18
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2017 OU18 is 0.572 AU from Earth today (4.8 light-minutes).

In the sky

Right ascension
17h 09m 28s
Declination
+21° 43′ 52″
Constellation
Hercules
Distance from Earth
0.57 AU
Elongation from the Sun
60.88° — well clear of the Sun

Favours the northern hemisphere; low or below the horizon from far south.

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
0.826 AU
Eccentricity
0.3775
Inclination
30.38°
Orbital period
274.1 days
Perihelion
0.514 AU
Aphelion
1.137 AU
Longitude of ascending node
302.21°
Argument of periapsis
185.26°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 45.6 LD
0.1173 AU
Tisserand (Jupiter)
6.938

Orbit quality

Orbit very well determined (uncertainty code 1).

Observations used
33
Data arc
11.99 years
First observed
25 July 2011
Last observed
21 July 2023
Residual RMS
0.56 ″
Solution · Otto Matic
22 July 2023

Visual & observation

Absolute magnitude (H)
23.98

Discovery & classification

Aten Near-Earth Object

Close approaches 135 on record

Flyby geometry
Ecliptic flyby of 2017 OU18 at 2029-07-24 04:47 UTC Top-down view of the ecliptic, Earth at the centre, for the 2029-07-24 04:47 UTC close approach of 2017 OU18. Catalogue miss distance 46.1 LD · 1.77 × 10⁷ km. The curve is the geocentric path from 2029-07-21 to 2029-07-27, 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 46.1 LD · 1.77 × 10⁷ km 2029-07-24 04:47 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2029-07-24 04:47 UTC close approach of 2017 OU18. Catalogue miss distance 46.1 LD · 1.77 × 10⁷ km. The curve is the geocentric path from 2029-07-21 to 2029-07-27, 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
2029-07-24 04:47:00 Earth 0.1184 AU 46.1 LD 15.2 km/s
2032-07-23 17:02:00 Earth 0.118 AU 45.9 LD 15.2 km/s
2035-07-24 05:18:00 Earth 0.1176 AU 45.8 LD 15.2 km/s
2038-07-23 17:47:00 Earth 0.1175 AU 45.7 LD 15.3 km/s
2041-07-23 06:10:00 Earth 0.1175 AU 45.7 LD 15.3 km/s
2044-07-22 18:10:00 Earth 0.1177 AU 45.8 LD 15.3 km/s
2047-07-23 05:40:00 Earth 0.118 AU 45.9 LD 15.3 km/s
2050-07-22 17:09:00 Earth 0.1188 AU 46.2 LD 15.3 km/s
2053-07-22 04:04:00 Earth 0.1198 AU 46.6 LD 15.4 km/s
2056-07-21 14:29:00 Earth 0.1212 AU 47.2 LD 15.4 km/s

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

Sources