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Asteroid Near-Earth

Cruithne

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3753 Cruithne (1986 TO)

Where is it now

Distance from Sun
0.95 AU
True anomaly
243.74°
Distance from Earth
0.674 AU
As of
11 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 — 0.998 AU from the Sun Earth Cruithne — 0.95 AU from the Sun Cruithne
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Cruithne is 0.674 AU from Earth today (5.6 light-minutes).

In the sky

Right ascension
08h 45m 23s
Declination
-09° 53′ 44″
Constellation
Hydra
Distance from Earth
0.67 AU
Elongation from the Sun
65.45° — well clear of the Sun

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
0.998 AU
Eccentricity
0.5149
Inclination
19.8°
Orbital period
364.1 days
Perihelion
0.484 AU
Aphelion
1.512 AU
Longitude of ascending node
126.19°
Argument of periapsis
43.88°
Epoch · J2000
2461200.5
Orbit class · ATE
Aten
Earth MOID · 27.5 LD
0.0707 AU
Tisserand (Jupiter)
5.921

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
1,717
Data arc
52.97 years
First observed
17 October 1973
Last observed
5 October 2026
Residual RMS
0.44 ″
Solution · Otto Matic
6 October 2026

Physical properties

Mean radius
1.04 km
Rotation period
27.31 hours

Visual & observation

Geometric albedo
0.365
Absolute magnitude (H)
15.42
Spectral type (SMASS)
Q

Discovery & classification

Discovered by
Waldron, J. D.
Discovery date
10 October 1986
Discovery site
Siding Spring

Named for the most common term used by the Irish for the Picts---one of the ancient peoples of Scotland. ‘Cruithne’ was the eponymous ancestor of the Picts, and it was his seven sons who gave their names to the seven divisions of the Pictish Kingdom.

Also known as 3753 · 1986 TO · 1983 UH

Aten Near-Earth Object Named

Close approaches 24 on record

When (UTC) Body Distance Lunar distances Relative speed
2058-02-19 18:12:00 Mars 0.0916 AU 35.6 LD 14.1 km/s
2060-10-07 05:01:00 Venus 0.15 AU 58.4 LD 20 km/s
2107-01-16 04:33:00 Mars 0.0959 AU 37.3 LD 14.4 km/s
2182-07-29 15:32:00 Venus 0.1487 AU 57.9 LD 20.3 km/s

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

Sources