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Comet

Harrington

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51P/Harrington-A

Where is it now

Distance from Sun
4.576 AU
True anomaly
214.23°
Distance from Earth
5.561 AU
As of
22 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.

Orbit of Mercury Orbit of Venus Orbit of Mars Sun Earth — 0.995 AU from the Sun Earth Harrington — 4.576 AU from the Sun Harrington
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Harrington is 5.561 AU from Earth today (46.2 light-minutes).

In the sky

Right ascension
13h 52m 17s
Declination
-03° 56′ 13″
Constellation
Virgo
Distance from Earth
5.56 AU
Elongation from the Sun
7.43° — too close to the Sun to observe

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
3.581 AU
Eccentricity
0.5621
Inclination
8.65°
Orbital period
6.78 years
Perihelion
1.568 AU
Aphelion
5.593 AU
Longitude of ascending node
119.19°
Argument of periapsis
233.59°
Epoch · J2000
2451677.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 226.4 LD
0.5817 AU
Tisserand (Jupiter)
2.81

Orbit quality

Orbit very well determined (uncertainty code 2).

Observations used
246
Data arc
20.79 years
First observed
10 September 1994
Last observed
25 June 2015
Residual RMS
0.86 ″
Solution · Davide Farnocchia
23 February 2016

Physical properties

Mean radius
2.40 km

Visual & observation

Absolute magnitude (H)
10.6
Total magnitude M₁ · K₁ 15
10.6

Discovery & classification

Also known as 51P-A

Named

Close approaches 12 on record

When (UTC) Body Distance Lunar distances Relative speed
2039-04-21 01:06:00 Jupiter 0.4364 AU 169.8 LD 5.6 km/s
2039-04-21 01:06:00 Juptr 0.4364 AU 169.8 LD 5.6 km/s
2063-09-10 16:17:00 Jupiter 0.4983 AU 193.9 LD 4.2 km/s
2063-09-10 16:17:00 Juptr 0.4983 AU 193.9 LD 4.2 km/s
2087-12-30 00:14:00 Juptr 0.1632 AU 63.5 LD 5.3 km/s
2087-12-30 00:14:00 Jupiter 0.1632 AU 63.5 LD 5.3 km/s

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

Sources