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Comet Near-Earth

Schwassmann-Wachmann

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73P/Schwassmann-Wachmann 3-L

Where is it now

Distance from Sun
4.08 AU
True anomaly
208.61°
Distance from Earth
4.336 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 Schwassmann-Wachmann — 4.08 AU from the Sun Schwassmann-Wachmann
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Schwassmann-Wachmann is 4.336 AU from Earth today (36.1 light-minutes).

In the sky

Right ascension
08h 59m 42s
Declination
+25° 17′ 07″
Constellation
Cancer
Distance from Earth
4.32 AU
Elongation from the Sun
69.2° — well clear of the Sun

Favours the northern hemisphere; low or below the horizon from far south.

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
3.076 AU
Eccentricity
0.6947
Inclination
11.4°
Orbital period
5.4 years
Perihelion
0.939 AU
Aphelion
5.214 AU
Longitude of ascending node
69.94°
Argument of periapsis
198.75°
Epoch · J2000
2453839.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 15.8 LD
0.0407 AU
Tisserand (Jupiter)
2.776

Orbit quality

Orbit poorly determined (uncertainty code 6).

Observations used
39
Data arc
58 days
First observed
5 March 2006
Last observed
2 May 2006
Residual RMS
1.25 ″
Solution · Nick Mastrodemos
7 May 2006

Visual & observation

Absolute magnitude (H)
20.9
Total magnitude M₁ · K₁ 10
20.9

Discovery & classification

Also known as 73P-L

Near-Earth Object Named

Close approaches 9 on record

When (UTC) Body Distance Lunar distances Relative speed
2037-05-06 06:50:00 Juptr 1.5314 AU 596.0 LD 11.5 km/s
2072-04-17 13:48:00 Juptr 0.4754 AU 185.0 LD 7.8 km/s
2072-04-17 13:48:00 Jupiter 0.4754 AU 185.0 LD 7.8 km/s
2084-09-24 11:42:00 Juptr 0.3102 AU 120.7 LD 6.5 km/s
2084-09-24 11:42:00 Jupiter 0.3102 AU 120.7 LD 6.5 km/s

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

Sources