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Comet Near-Earth

Boethin

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85D/Boethin

Where is it now

Distance from Sun
9.233 AU
True anomaly
180.7°
Distance from Earth
10.18 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.

Orbit of Mercury Orbit of Venus Orbit of Mars Sun Earth — 0.998 AU from the Sun Earth Boethin — 9.233 AU from the Sun Boethin
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Boethin is 10.18 AU from Earth today (1.4 light-hours).

In the sky

Right ascension
14h 10m 54s
Declination
-15° 45′ 10″
Constellation
Virgo
Distance from Earth
10.18 AU
Elongation from the Sun
16.91° — too close to the Sun to observe

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
5.185 AU
Eccentricity
0.7812
Inclination
4.3°
Orbital period
11.81 years
Perihelion
1.135 AU
Aphelion
9.235 AU
Longitude of ascending node
359.4°
Argument of periapsis
37.62°
Epoch · J2000
2454252.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 58.3 LD
0.1499 AU
Tisserand (Jupiter)
2.247

Orbit quality

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

Observations used
51
Data arc
11.07 years
First observed
5 February 1975
Last observed
1 March 1986
Residual RMS
1.66 ″
Solution · Steven R. Chesley
25 September 2007

Discovery & classification

Also known as 85D · 1975 I · 1975a · 1985n · 1986 I · 85D/1975 A1 · 85D/1985 T2

Near-Earth Object Named

Close approaches 5 on record

When (UTC) Body Distance Lunar distances Relative speed
2123-11-22 19:21:00 Juptr 1.6157 AU 628.8 LD 14.6 km/s

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

Sources