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Asteroid Near-Earth

2015 OQ21

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(2015 OQ21)

Where is it now

Distance from Sun
1.003 AU
True anomaly
209.37°
Distance from Earth
1.282 AU
As of
16 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 — 0.997 AU from the Sun Earth 2015 OQ21 — 1.003 AU from the Sun 2015 OQ21
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2015 OQ21 is 1.282 AU from Earth today (10.7 light-minutes).

In the sky

Right ascension
16h 50m 40s
Declination
-22° 26′ 30″
Constellation
Ophiuchus
Distance from Earth
1.28 AU
Elongation from the Sun
50.22° — near the Sun — look low at dusk or dawn

Favours the southern hemisphere; low or below the horizon from far north.

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
0.789 AU
Eccentricity
0.364
Inclination
1.62°
Orbital period
256.1 days
Perihelion
0.502 AU
Aphelion
1.076 AU
Longitude of ascending node
125.77°
Argument of periapsis
328.45°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 1.0 LD
0.0026 AU
Tisserand (Jupiter)
7.319

Orbit quality

Orbit reasonably well determined (uncertainty code 3).

Observations used
60
Data arc
6 days
First observed
19 July 2015
Last observed
25 July 2015
Residual RMS
0.43 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
27.9

Discovery & classification

Aten Near-Earth Object

Close approaches 247 on record

Flyby geometry
Ecliptic flyby of 2015 OQ21 at 2027-01-23 07:26 UTC Top-down view of the ecliptic, Earth at the centre, for the 2027-01-23 07:26 UTC close approach of 2015 OQ21. Catalogue miss distance 180.6 LD · 6.94 × 10⁷ km. The curve is the geocentric path from 2027-01-20 to 2027-01-26, 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 180.6 LD · 6.94 × 10⁷ km 2027-01-23 07:26 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2027-01-23 07:26 UTC close approach of 2015 OQ21. Catalogue miss distance 180.6 LD · 6.94 × 10⁷ km. The curve is the geocentric path from 2027-01-20 to 2027-01-26, 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
2027-01-23 07:26:00 Earth 0.464 AU 180.6 LD 17.2 km/s
2027-07-16 18:01:00 Earth 0.4381 AU 170.5 LD 21.8 km/s
2029-06-24 21:02:00 Earth 0.0618 AU 24.0 LD 6.4 km/s
2030-06-06 04:10:00 Venus 0.1325 AU 51.6 LD 19.1 km/s
2031-06-06 01:45:00 Earth 0.4483 AU 174.5 LD 22.1 km/s
2031-11-27 21:39:00 Earth 0.4659 AU 181.3 LD 17.2 km/s
2034-01-28 16:37:00 Earth 0.4565 AU 177.7 LD 16.5 km/s
2034-07-18 13:32:00 Earth 0.3881 AU 151.0 LD 20.2 km/s
2036-06-12 00:37:00 Earth 0.0535 AU 20.8 LD 6.5 km/s
2038-06-07 17:10:00 Earth 0.493 AU 191.9 LD 23.6 km/s

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

Sources