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Asteroid Near-Earth

2021 XF

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(2021 XF)

Where is it now

Distance from Sun
0.932 AU
True anomaly
132°
Distance from Earth
0.581 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 XF — 0.932 AU from the Sun 2021 XF
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2021 XF is 0.581 AU from Earth today (4.8 light-minutes).

In the sky

Right ascension
18h 03m 02s
Declination
-16° 30′ 32″
Constellation
Sagittarius
Distance from Earth
0.58 AU
Elongation from the Sun
66.79° — well clear of the Sun

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
0.815 AU
Eccentricity
0.3215
Inclination
4.37°
Orbital period
269 days
Perihelion
0.553 AU
Aphelion
1.078 AU
Longitude of ascending node
249.48°
Argument of periapsis
327.24°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 1.8 LD
0.0047 AU
Tisserand (Jupiter)
7.129

Orbit quality

Orbit poorly determined (uncertainty code 7).

Observations used
21
Data arc
2 days
First observed
1 December 2021
Last observed
3 December 2021
Residual RMS
0.19 ″
Solution · Otto Matic
4 December 2021

Visual & observation

Absolute magnitude (H)
28.35

Discovery & classification

Aten Near-Earth Object

Close approaches 169 on record

Flyby geometry
Ecliptic flyby of 2021 XF at 2027-04-28 20:51 UTC Top-down view of the ecliptic, Earth at the centre, for the 2027-04-28 20:51 UTC close approach of 2021 XF. Catalogue miss distance 176.9 LD · 6.8 × 10⁷ km. The curve is the geocentric path from 2027-04-25 to 2027-05-01, 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 176.9 LD · 6.8 × 10⁷ km 2027-04-28 20:51 UTC Earth Moon Heliocentric, approximate

Top-down view of the ecliptic, Earth at the centre, for the 2027-04-28 20:51 UTC close approach of 2021 XF. Catalogue miss distance 176.9 LD · 6.8 × 10⁷ km. The curve is the geocentric path from 2027-04-25 to 2027-05-01, 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
2027-04-28 20:51:00 Earth 0.4545 AU 176.9 LD 16.6 km/s
2029-06-04 09:34:00 Venus 0.1353 AU 52.7 LD 16.7 km/s
2029-09-28 23:49:00 Earth 0.2538 AU 98.8 LD 15.7 km/s
2030-03-23 21:48:00 Earth 0.4226 AU 164.5 LD 14.3 km/s
2032-10-08 18:29:00 Earth 0.0819 AU 31.9 LD 6.8 km/s
2034-01-19 11:00:00 Venus 0.1074 AU 41.8 LD 15.1 km/s
2035-07-08 15:00:00 Earth 0.3644 AU 141.8 LD 9.9 km/s
2035-12-07 16:40:00 Earth 0.0431 AU 16.8 LD 9.3 km/s
2037-09-23 15:10:00 Venus 0.0755 AU 29.4 LD 11.7 km/s
2038-05-27 01:55:00 Earth 0.4424 AU 172.2 LD 15.5 km/s

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

Sources