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Comet

Larsen

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280P/Larsen

Where is it now

Distance from Sun
5.93 AU
True anomaly
152.86°
Distance from Earth
4.959 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 Larsen — 5.93 AU from the Sun Larsen
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Larsen is 4.959 AU from Earth today (41.2 light-minutes).

In the sky

Right ascension
02h 06m 24s
Declination
-01° 53′ 18″
Constellation
Cetus
Distance from Earth
4.96 AU
Elongation from the Sun
166.14° — near opposition — up most of the night

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
4.513 AU
Eccentricity
0.4177
Inclination
11.78°
Orbital period
9.59 years
Perihelion
2.628 AU
Aphelion
6.398 AU
Longitude of ascending node
131.49°
Argument of periapsis
104.86°
Epoch · J2000
2455021.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 641.5 LD
1.6483 AU
Tisserand (Jupiter)
2.81

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
166
Data arc
19.02 years
First observed
19 April 2004
Last observed
28 April 2023
Residual RMS
0.75 ″
Solution · Otto Matic
11 September 2024

Visual & observation

Absolute magnitude (H)
15.2
Total magnitude M₁ · K₁ 4.5
15.2

Discovery & classification

Also known as 280P · 280P/2004 H2 · 280P/2013 C1

Named

Close approaches 13 on record

When (UTC) Body Distance Lunar distances Relative speed
2049-04-02 19:29:00 Juptr 1.3127 AU 510.9 LD 4.2 km/s
2093-09-29 02:28:00 Juptr 1.0263 AU 399.4 LD 8.4 km/s
2107-11-20 07:11:00 Juptr 1.7524 AU 682.0 LD 4.5 km/s
2120-06-02 23:27:00 Juptr 1.9824 AU 771.5 LD 11.4 km/s
2165-01-28 12:20:00 Juptr 1.7749 AU 690.8 LD 10.7 km/s
2178-02-19 00:27:00 Juptr 1.9003 AU 739.5 LD 4.7 km/s
2191-11-09 03:22:00 Juptr 0.7923 AU 308.4 LD 8.2 km/s

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

Sources