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Asteroid Near-Earth

2021 KJ1

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(2021 KJ1)

Where is it now

Distance from Sun
0.399 AU
True anomaly
49.9°
Distance from Earth
1.049 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 KJ1 — 0.399 AU from the Sun 2021 KJ1
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 KJ1 is 1.049 AU from Earth today (8.7 light-minutes).

In the sky

Right ascension
12h 03m 37s
Declination
-00° 41′ 36″
Constellation
Virgo
Distance from Earth
1.05 AU
Elongation from the Sun
22.32° — near the Sun — look low at dusk or dawn

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
0.737 AU
Eccentricity
0.5251
Inclination
6.75°
Orbital period
231.3 days
Perihelion
0.35 AU
Aphelion
1.125 AU
Longitude of ascending node
115.96°
Argument of periapsis
303.7°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 23.1 LD
0.0593 AU
Tisserand (Jupiter)
7.692

Orbit quality

Orbit poorly determined (uncertainty code 7).

Observations used
32
Data arc
18 days
First observed
18 May 2021
Last observed
5 June 2021
Residual RMS
0.36 ″
Solution · Otto Matic
6 June 2021

Visual & observation

Absolute magnitude (H)
24

Discovery & classification

Aten Near-Earth Object

Close approaches 102 on record

Flyby geometry
Ecliptic flyby of 2021 KJ1 at 2028-02-05 05:34 UTC Top-down view of the ecliptic, Earth at the centre, for the 2028-02-05 05:34 UTC close approach of 2021 KJ1. Catalogue miss distance 193.7 LD · 7.45 × 10⁷ km. The curve is the geocentric path from 2028-02-02 to 2028-02-08, 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. The path is a geocentric ecliptic ephemeris from JPL Horizons. The inset is a heliocentric view and is approximate. Sun 193.7 LD · 7.45 × 10⁷ km 2028-02-05 05:34 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2028-02-05 05:34 UTC close approach of 2021 KJ1. Catalogue miss distance 193.7 LD · 7.45 × 10⁷ km. The curve is the geocentric path from 2028-02-02 to 2028-02-08, 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. 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
2028-02-05 05:34:00 Earth 0.4977 AU 193.7 LD 15.1 km/s
2028-06-17 01:03:00 Earth 0.067 AU 26.1 LD 11.9 km/s
2031-05-05 20:13:00 Earth 0.4863 AU 189.3 LD 28 km/s
2033-03-17 13:52:00 Venus 0.1117 AU 43.5 LD 14.4 km/s
2033-04-27 13:38:00 Earth 0.1292 AU 50.3 LD 10.8 km/s
2033-10-31 01:30:00 Venus 0.0418 AU 16.3 LD 20.5 km/s
2035-06-18 04:54:00 Earth 0.1404 AU 54.6 LD 16.8 km/s
2038-02-26 08:18:00 Merc 0.0593 AU 23.1 LD 10.7 km/s
2038-02-26 08:18:00 Mercury 0.0593 AU 23.1 LD 10.7 km/s
2038-04-28 08:50:00 Earth 0.3245 AU 126.3 LD 22.2 km/s

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

Sources