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Asteroid Near-Earth

2021 XA1

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(2021 XA1)

Where is it now

Distance from Sun
0.979 AU
True anomaly
160.32°
Distance from Earth
0.597 AU
As of
15 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 XA1 — 0.979 AU from the Sun 2021 XA1
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 XA1 is 0.597 AU from Earth today (5.0 light-minutes).

In the sky

Right ascension
08h 57m 04s
Declination
+15° 55′ 31″
Constellation
Cancer
Distance from Earth
0.59 AU
Elongation from the Sun
71.17° — well clear of the Sun

Favours the northern hemisphere; low or below the horizon from far south.

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
0.723 AU
Eccentricity
0.4097
Inclination
6.31°
Orbital period
224.4 days
Perihelion
0.427 AU
Aphelion
1.019 AU
Longitude of ascending node
65.28°
Argument of periapsis
191.9°
Epoch · J2000
2459550.5
Orbit class · ATE
Aten
Earth MOID · 3.5 LD
0.0091 AU
Tisserand (Jupiter)
7.875

Orbit quality

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

Observations used
30
Data arc
6 days
First observed
29 November 2021
Last observed
5 December 2021
Residual RMS
0.47 ″
Solution · Otto Matic
17 August 2022

Visual & observation

Absolute magnitude (H)
26.98

Discovery & classification

Aten Near-Earth Object

Close approaches 92 on record

Flyby geometry
Ecliptic flyby of 2021 XA1 at 2026-12-27 08:35 UTC Top-down view of the ecliptic, Earth at the centre, for the 2026-12-27 08:35 UTC close approach of 2021 XA1. Catalogue miss distance 131.2 LD · 5.04 × 10⁷ km. The curve is the geocentric path from 2026-12-24 to 2026-12-30, 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 131.2 LD · 5.04 × 10⁷ km 2026-12-27 08:35 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2026-12-27 08:35 UTC close approach of 2021 XA1. Catalogue miss distance 131.2 LD · 5.04 × 10⁷ km. The curve is the geocentric path from 2026-12-24 to 2026-12-30, 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
2026-12-27 08:35:00 Earth 0.337 AU 131.2 LD 19.9 km/s
2032-11-19 21:55:00 Earth 0.28 AU 109.0 LD 18.3 km/s
2034-12-26 01:44:00 Earth 0.3707 AU 144.3 LD 21.1 km/s
2036-06-01 12:42:00 Merc 0.081 AU 31.5 LD 26.5 km/s
2036-06-01 12:42:00 Mercury 0.081 AU 31.5 LD 26.5 km/s
2040-11-19 04:51:00 Earth 0.2612 AU 101.6 LD 17.7 km/s
2042-12-25 13:22:00 Earth 0.3838 AU 149.3 LD 21.6 km/s
2048-11-19 01:44:00 Earth 0.2605 AU 101.4 LD 17.7 km/s
2050-12-25 16:25:00 Earth 0.3795 AU 147.7 LD 21.5 km/s
2056-11-19 10:02:00 Earth 0.2755 AU 107.2 LD 18.2 km/s

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

Sources