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Asteroid Near-Earth

2021 CY5

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(2021 CY5)

Where is it now

Distance from Sun
1.103 AU
True anomaly
183.82°
Distance from Earth
2.06 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 2021 CY5 — 1.103 AU from the Sun 2021 CY5
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 CY5 is 2.06 AU from Earth today (17.1 light-minutes).

In the sky

Right ascension
12h 58m 54s
Declination
-04° 47′ 39″
Constellation
Virgo
Distance from Earth
2.06 AU
Elongation from the Sun
11.73° — too close to the Sun to observe

Visible from both hemispheres.

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
0.855 AU
Eccentricity
0.2922
Inclination
4.79°
Orbital period
288.6 days
Perihelion
0.605 AU
Aphelion
1.104 AU
Longitude of ascending node
152.38°
Argument of periapsis
208.28°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 8.7 LD
0.0224 AU
Tisserand (Jupiter)
6.861

Orbit quality

Orbit very well determined (uncertainty code 1).

Observations used
57
Data arc
4.13 years
First observed
10 February 2021
Last observed
28 March 2025
Residual RMS
0.56 ″
Solution · Otto Matic
29 March 2025

Visual & observation

Absolute magnitude (H)
25.65

Discovery & classification

Aten Near-Earth Object

Close approaches 109 on record

Flyby geometry
Ecliptic flyby of 2021 CY5 at 2036-02-05 13:26 UTC Top-down view of the ecliptic, Earth at the centre, for the 2036-02-05 13:26 UTC close approach of 2021 CY5. Catalogue miss distance 21.6 LD · 8.31 × 10⁶ km. The curve is the geocentric path from 2036-02-02 to 2036-02-08, 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 21.6 LD · 8.31 × 10⁶ km 2036-02-05 13:26 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2036-02-05 13:26 UTC close approach of 2021 CY5. Catalogue miss distance 21.6 LD · 8.31 × 10⁶ km. The curve is the geocentric path from 2036-02-02 to 2036-02-08, 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
2027-11-22 08:04:00 Venus 0.0866 AU 33.7 LD 7.5 km/s
2033-05-28 13:17:00 Venus 0.0679 AU 26.4 LD 8.8 km/s
2036-02-05 13:26:00 Earth 0.0556 AU 21.6 LD 9.3 km/s
2038-12-08 20:44:00 Venus 0.065 AU 25.3 LD 9.7 km/s
2040-03-20 04:48:00 Earth 0.1164 AU 45.3 LD 6.4 km/s
2044-05-01 10:01:00 Earth 0.1098 AU 42.7 LD 9.9 km/s
2044-06-21 09:35:00 Venus 0.0655 AU 25.5 LD 10.1 km/s
2050-01-01 13:58:00 Venus 0.0756 AU 29.4 LD 11.6 km/s
2051-02-07 13:03:00 Earth 0.1819 AU 70.8 LD 13.4 km/s
2055-02-22 22:23:00 Earth 0.0843 AU 32.8 LD 6.3 km/s

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

Sources