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Comet

Denning

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489P/Denning

Where is it now

Distance from Sun
3.117 AU
True anomaly
105.15°
Distance from Earth
4.033 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 Denning — 3.117 AU from the Sun Denning
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Denning is 4.033 AU from Earth today (33.5 light-minutes).

In the sky

Right ascension
15h 06m 43s
Declination
-19° 16′ 07″
Constellation
Libra
Distance from Earth
4.04 AU
Elongation from the Sun
19.64° — 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
4.443 AU
Eccentricity
0.6456
Inclination
4.01°
Orbital period
9.37 years
Perihelion
1.575 AU
Aphelion
7.312 AU
Longitude of ascending node
22.58°
Argument of periapsis
107.96°
Epoch · J2000
2452504.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 232.0 LD
0.5961 AU
Tisserand (Jupiter)
2.579

Orbit quality

Orbit reasonably well determined (uncertainty code 3).

Observations used
302
Data arc
113.1 years
First observed
27 March 1894
Last observed
18 May 2007
Residual RMS
0.6 ″
Solution · Otto Matic
11 October 2024

Visual & observation

Absolute magnitude (H)
7.6
Total magnitude M₁ · K₁ 49.3
7.6

Discovery & classification

Also known as 489P · 489P/1894 F1 · 489P/2007 HE4

Named

Close approaches 13 on record

When (UTC) Body Distance Lunar distances Relative speed
2033-11-17 00:58:00 Juptr 1.7887 AU 696.1 LD 13.9 km/s
2055-07-12 09:23:00 Juptr 0.4328 AU 168.4 LD 9.7 km/s
2055-07-12 09:23:00 Jupiter 0.4328 AU 168.4 LD 9.7 km/s
2129-03-29 17:12:00 Juptr 0.1454 AU 56.6 LD 9.6 km/s
2129-03-29 17:12:00 Jupiter 0.1454 AU 56.6 LD 9.6 km/s

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

Sources