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Asteroid Near-Earth

2021 RG2

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(2021 RG2)

Where is it now

Distance from Sun
1.067 AU
True anomaly
189.73°
Distance from Earth
0.189 AU
As of
20 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 2021 RG2 — 1.067 AU from the Sun 2021 RG2
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 RG2 is 0.189 AU from Earth today (1.6 light-minutes).

In the sky

Right ascension
02h 55m 12s
Declination
-60° 52′ 33″
Constellation
Horologium
Distance from Earth
0.19 AU
Elongation from the Sun
107.04° — well clear of the Sun

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
0.883 AU
Eccentricity
0.2136
Inclination
14.78°
Orbital period
302.9 days
Perihelion
0.694 AU
Aphelion
1.071 AU
Longitude of ascending node
165.87°
Argument of periapsis
30.73°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 8.0 LD
0.0205 AU
Tisserand (Jupiter)
6.674

Orbit quality

Orbit reasonably well determined (uncertainty code 5).

Observations used
193
Data arc
4 days
First observed
6 September 2021
Last observed
10 September 2021
Residual RMS
0.44 ″
Solution · Otto Matic
10 August 2022

Visual & observation

Absolute magnitude (H)
25.38

Discovery & classification

Aten Near-Earth Object

Close approaches 164 on record

Flyby geometry
Ecliptic flyby of 2021 RG2 at 2027-01-21 17:45 UTC Top-down view of the ecliptic, Earth at the centre, for the 2027-01-21 17:45 UTC close approach of 2021 RG2. Catalogue miss distance 95.1 LD · 3.66 × 10⁷ km. The curve is the geocentric path from 2027-01-18 to 2027-01-24, 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. At closest approach the object is south of the ecliptic. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 95.1 LD · 3.66 × 10⁷ km 2027-01-21 17:45 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2027-01-21 17:45 UTC close approach of 2021 RG2. Catalogue miss distance 95.1 LD · 3.66 × 10⁷ km. The curve is the geocentric path from 2027-01-18 to 2027-01-24, 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. At closest approach the object is south of the ecliptic. 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
2027-01-21 17:45:00 Earth 0.2444 AU 95.1 LD 9.7 km/s
2031-06-03 07:27:00 Earth 0.347 AU 135.0 LD 7.5 km/s
2031-10-20 06:53:00 Earth 0.2383 AU 92.7 LD 8.4 km/s
2036-04-04 01:34:00 Venus 0.1279 AU 49.8 LD 13.7 km/s
2036-05-02 11:19:00 Earth 0.3523 AU 137.1 LD 11 km/s
2036-11-21 11:45:00 Earth 0.3273 AU 127.4 LD 12 km/s
2038-10-06 04:02:00 Venus 0.0478 AU 18.6 LD 10.5 km/s
2040-09-09 03:32:00 Earth 0.3602 AU 140.2 LD 17.8 km/s
2041-04-07 23:56:00 Earth 0.3299 AU 128.4 LD 12.4 km/s
2041-11-15 21:40:00 Earth 0.4535 AU 176.5 LD 17.3 km/s

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

Sources