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Asteroid Near-Earth

2021 GU3

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(2021 GU3)

Where is it now

Distance from Sun
0.495 AU
True anomaly
322.73°
Distance from Earth
0.62 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 2021 GU3 — 0.495 AU from the Sun 2021 GU3
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 GU3 is 0.62 AU from Earth today (5.2 light-minutes).

In the sky

Right ascension
14h 54m 25s
Declination
-19° 00′ 08″
Constellation
Libra
Distance from Earth
0.62 AU
Elongation from the Sun
23.31° — 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
0.748 AU
Eccentricity
0.3753
Inclination
7.71°
Orbital period
236.4 days
Perihelion
0.467 AU
Aphelion
1.029 AU
Longitude of ascending node
15.34°
Argument of periapsis
15.24°
Epoch · J2000
2459312.5
Orbit class · ATE
Aten
Earth MOID · 1.9 LD
0.0049 AU
Tisserand (Jupiter)
7.651

Orbit quality

Orbit very uncertain — the object may be effectively lost (uncertainty code 8).

Observations used
21
Data arc
24 hours
First observed
7 April 2021
Last observed
8 April 2021
Residual RMS
0.38 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
26.9

Discovery & classification

Aten Near-Earth Object

Close approaches 44 on record

Flyby geometry
Ecliptic flyby of 2021 GU3 at 2030-04-02 15:18 UTC Top-down view of the ecliptic, Earth at the centre, for the 2030-04-02 15:18 UTC close approach of 2021 GU3. Catalogue miss distance 140.2 LD · 5.39 × 10⁷ km. The curve is the geocentric path from 2030-03-30 to 2030-04-05, 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 140.2 LD · 5.39 × 10⁷ km 2030-04-02 15:18 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2030-04-02 15:18 UTC close approach of 2021 GU3. Catalogue miss distance 140.2 LD · 5.39 × 10⁷ km. The curve is the geocentric path from 2030-03-30 to 2030-04-05, 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
2028-03-25 00:02:00 Venus 0.0629 AU 24.5 LD 16 km/s
2030-04-02 15:18:00 Earth 0.3602 AU 140.2 LD 19.4 km/s
2034-05-10 04:27:00 Earth 0.1182 AU 46.0 LD 10.1 km/s
2036-05-04 23:52:00 Earth 0.402 AU 156.4 LD 20.4 km/s
2040-07-15 18:41:00 Venus 0.1115 AU 43.4 LD 18.8 km/s
2041-04-06 05:19:00 Earth 0.4544 AU 176.8 LD 22.5 km/s
2043-03-27 22:29:00 Earth 0.1401 AU 54.5 LD 12 km/s
2047-05-08 22:49:00 Earth 0.3081 AU 119.9 LD 17.1 km/s
2049-05-23 08:30:00 Venus 0.0794 AU 30.9 LD 14.6 km/s
2052-03-20 14:27:00 Venus 0.0849 AU 33.1 LD 10.6 km/s

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

Sources