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Comet

Larson

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250P/Larson

Where is it now

Distance from Sun
3.949 AU
True anomaly
121.29°
Distance from Earth
4.828 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 Larson — 3.949 AU from the Sun Larson
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Larson is 4.828 AU from Earth today (40.2 light-minutes).

In the sky

Right ascension
15h 30m 39s
Declination
-16° 24′ 09″
Constellation
Libra
Distance from Earth
4.83 AU
Elongation from the Sun
24.79° — near the Sun — look low at dusk or dawn

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
3.733 AU
Eccentricity
0.4074
Inclination
13.29°
Orbital period
7.21 years
Perihelion
2.212 AU
Aphelion
5.254 AU
Longitude of ascending node
73.71°
Argument of periapsis
45.03°
Epoch · J2000
2457258.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 486.9 LD
1.2512 AU
Tisserand (Jupiter)
2.899

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
571
Data arc
30.41 years
First observed
22 December 1995
Last observed
22 May 2026
Residual RMS
0.6 ″
Solution · Otto Matic
28 May 2026

Visual & observation

Absolute magnitude (H)
14.6
Total magnitude M₁ · K₁ 10.8
14.6

Discovery & classification

Also known as 250P · 250P/2011 A1

Named

Close approaches 8 on record

When (UTC) Body Distance Lunar distances Relative speed
2045-03-27 08:07:00 Juptr 1.5733 AU 612.3 LD 7.2 km/s
2080-11-12 21:58:00 Juptr 1.168 AU 454.5 LD 5.5 km/s
2126-11-20 15:36:00 Juptr 1.1178 AU 435.0 LD 7.3 km/s
2162-07-02 02:32:00 Juptr 1.3648 AU 531.1 LD 8 km/s

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

Sources