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Asteroid Near-Earth

2021 CP9

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(2021 CP9)

Where is it now

Distance from Sun
0.87 AU
True anomaly
231.34°
Distance from Earth
1.854 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 CP9 — 0.87 AU from the Sun 2021 CP9
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 CP9 is 1.854 AU from Earth today (15.4 light-minutes).

In the sky

Right ascension
13h 27m 32s
Declination
-15° 26′ 04″
Constellation
Virgo
Distance from Earth
1.85 AU
Elongation from the Sun
6.23° — too close to the Sun to observe

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
0.776 AU
Eccentricity
0.3097
Inclination
14.85°
Orbital period
249.7 days
Perihelion
0.536 AU
Aphelion
1.016 AU
Longitude of ascending node
332.06°
Argument of periapsis
5.73°
Epoch · J2000
2459262.5
Orbit class · ATE
Aten
Earth MOID · 9.7 LD
0.025 AU
Tisserand (Jupiter)
7.415

Orbit quality

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

Observations used
28
Data arc
6 days
First observed
15 February 2021
Last observed
21 February 2021
Residual RMS
0.54 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
26.97

Discovery & classification

Aten Near-Earth Object

Close approaches 20 on record

Flyby geometry
Ecliptic flyby of 2021 CP9 at 2027-08-29 03:04 UTC Top-down view of the ecliptic, Earth at the centre, for the 2027-08-29 03:04 UTC close approach of 2021 CP9. Catalogue miss distance 184.3 LD · 7.09 × 10⁷ km. The curve is the geocentric path from 2027-08-26 to 2027-09-01, 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 184.3 LD · 7.09 × 10⁷ km 2027-08-29 03:04 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2027-08-29 03:04 UTC close approach of 2021 CP9. Catalogue miss distance 184.3 LD · 7.09 × 10⁷ km. The curve is the geocentric path from 2027-08-26 to 2027-09-01, 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
2027-08-29 03:04:00 Earth 0.4736 AU 184.3 LD 19.5 km/s
2032-03-12 17:06:00 Earth 0.235 AU 91.4 LD 13.6 km/s
2036-02-08 00:05:00 Earth 0.2463 AU 95.9 LD 14.6 km/s
2094-09-02 08:54:00 Earth 0.4736 AU 184.3 LD 19.5 km/s
2097-03-09 04:09:00 Earth 0.477 AU 185.6 LD 21.8 km/s
2099-03-13 02:14:00 Earth 0.2051 AU 79.8 LD 12.6 km/s
2166-02-08 16:24:00 Earth 0.2268 AU 88.3 LD 14 km/s

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

Sources