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Asteroid Near-Earth

2021 CU1

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(2021 CU1)

Where is it now

Distance from Sun
0.77 AU
True anomaly
305.41°
Distance from Earth
1.759 AU
As of
22 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 — 0.995 AU from the Sun Earth 2021 CU1 — 0.77 AU from the Sun 2021 CU1
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 CU1 is 1.759 AU from Earth today (14.6 light-minutes).

In the sky

Right ascension
13h 35m 04s
Declination
-10° 51′ 32″
Constellation
Virgo
Distance from Earth
1.76 AU
Elongation from the Sun
3.87° — 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
0.95 AU
Eccentricity
0.2599
Inclination
2.35°
Orbital period
338.1 days
Perihelion
0.703 AU
Aphelion
1.197 AU
Longitude of ascending node
321.9°
Argument of periapsis
293.16°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 0.0 LD
0.0001 AU
Tisserand (Jupiter)
6.303

Orbit quality

Orbit reasonably well determined (uncertainty code 5).

Observations used
32
Data arc
5 days
First observed
5 February 2021
Last observed
10 February 2021
Residual RMS
0.33 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
28.6

Discovery & classification

Listed by JPL impact monitoring; see the Sentry table for current probabilities.

Aten Near-Earth Object

Close approaches 41 on record

Flyby geometry
Ecliptic flyby of 2021 CU1 at 2030-10-18 16:44 UTC Top-down view of the ecliptic, Earth at the centre, for the 2030-10-18 16:44 UTC close approach of 2021 CU1. Catalogue miss distance 164.3 LD · 6.32 × 10⁷ km. The curve is the geocentric path from 2030-10-15 to 2030-10-21, 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 164.3 LD · 6.32 × 10⁷ km 2030-10-18 16:44 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2030-10-18 16:44 UTC close approach of 2021 CU1. Catalogue miss distance 164.3 LD · 6.32 × 10⁷ km. The curve is the geocentric path from 2030-10-15 to 2030-10-21, 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
2027-11-12 04:26:00 Venus 0.0051 AU 2.0 LD 6.6 km/s
2029-09-27 02:03:00 Venus 0.0817 AU 31.8 LD 10.2 km/s
2030-10-18 16:44:00 Earth 0.4222 AU 164.3 LD 21.2 km/s
2031-10-03 11:59:00 Earth 0.0288 AU 11.2 LD 8 km/s
2044-10-03 08:09:00 Earth 0.0287 AU 11.2 LD 8.4 km/s

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

Sources