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Asteroid Near-Earth

2021 RY3

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(2021 RY3)

Where is it now

Distance from Sun
0.795 AU
True anomaly
118.84°
Distance from Earth
1.545 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 RY3 — 0.795 AU from the Sun 2021 RY3
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 RY3 is 1.545 AU from Earth today (12.9 light-minutes).

In the sky

Right ascension
15h 00m 59s
Declination
-24° 13′ 27″
Constellation
Libra
Distance from Earth
1.55 AU
Elongation from the Sun
26.86° — 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
0.77 AU
Eccentricity
0.4204
Inclination
13.52°
Orbital period
246.6 days
Perihelion
0.446 AU
Aphelion
1.093 AU
Longitude of ascending node
344.32°
Argument of periapsis
160.28°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 10.7 LD
0.0275 AU
Tisserand (Jupiter)
7.439

Orbit quality

Orbit poorly determined (uncertainty code 7).

Observations used
26
Data arc
5 days
First observed
7 September 2021
Last observed
12 September 2021
Residual RMS
0.51 ″
Solution · Otto Matic
13 September 2021

Visual & observation

Absolute magnitude (H)
25.66

Discovery & classification

Aten Near-Earth Object

Close approaches 26 on record

Flyby geometry
Ecliptic flyby of 2021 RY3 at 2027-07-28 13:30 UTC Top-down view of the ecliptic, Earth at the centre, for the 2027-07-28 13:30 UTC close approach of 2021 RY3. Catalogue miss distance 71.6 LD · 2.75 × 10⁷ km. The curve is the geocentric path from 2027-07-25 to 2027-07-31, 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 71.6 LD · 2.75 × 10⁷ km 2027-07-28 13:30 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2027-07-28 13:30 UTC close approach of 2021 RY3. Catalogue miss distance 71.6 LD · 2.75 × 10⁷ km. The curve is the geocentric path from 2027-07-25 to 2027-07-31, 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
2027-07-28 13:30:00 Earth 0.1839 AU 71.6 LD 11.8 km/s
2027-12-08 12:16:00 Earth 0.4644 AU 180.7 LD 12.7 km/s
2029-07-25 23:35:00 Earth 0.2735 AU 106.4 LD 15.9 km/s
2031-07-29 23:39:00 Earth 0.3948 AU 153.7 LD 20.7 km/s
2042-09-08 13:04:00 Earth 0.3715 AU 144.6 LD 21.9 km/s
2044-09-12 21:34:00 Earth 0.2265 AU 88.1 LD 17.2 km/s
2046-09-15 08:17:00 Earth 0.089 AU 34.6 LD 13 km/s
2054-07-26 02:20:00 Earth 0.2263 AU 88.1 LD 13.9 km/s
2056-07-27 09:52:00 Earth 0.3383 AU 131.6 LD 18.5 km/s
2058-08-01 17:17:00 Earth 0.4691 AU 182.6 LD 23.4 km/s

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

Sources