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Comet

McMillan

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P/2010 J3 (McMillan)

Where is it now

Distance from Sun
15.083 AU
True anomaly
188.46°
Distance from Earth
14.635 AU
As of
24 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 — 0.994 AU from the Sun Earth McMillan — 15.083 AU from the Sun McMillan
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. McMillan is 14.635 AU from Earth today (2.0 light-hours).

In the sky

Right ascension
06h 26m 26s
Declination
+19° 58′ 00″
Constellation
Gemini
Distance from Earth
14.63 AU
Elongation from the Sun
115.27° — 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
8.987 AU
Eccentricity
0.7268
Inclination
13.26°
Orbital period
26.94 years
Perihelion
2.455 AU
Aphelion
15.519 AU
Longitude of ascending node
106.66°
Argument of periapsis
157.31°
Epoch · J2000
2455356.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 562.5 LD
1.4454 AU
Tisserand (Jupiter)
2.336

Orbit quality

Orbit reasonably well determined (uncertainty code 4).

Observations used
524
Data arc
594 days
First observed
3 February 2010
Last observed
20 September 2011
Residual RMS
0.49 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
11.4
Total magnitude M₁ · K₁ 11.5
11.4

Discovery & classification

Also known as 2010 J3 · P/2010 CG6

Named

Close approaches 3 on record

When (UTC) Body Distance Lunar distances Relative speed
2062-11-14 08:13:00 Juptr 1.3753 AU 535.2 LD 13.3 km/s
2147-03-03 15:03:00 Satrn 1.5157 AU 589.9 LD 8.5 km/s

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

Sources