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Comet Near-Earth

Schwassmann-Wachmann

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73P/Schwassmann-Wachmann 3-BN

Where is it now

Distance from Sun
3.485 AU
True anomaly
218.14°
Distance from Earth
3.905 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 — 3.485 AU from the Sun Schwassmann-Wachmann
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Schwassmann-Wachmann is 3.905 AU from Earth today (32.5 light-minutes).

In the sky

Right ascension
09h 43m 55s
Declination
+22° 38′ 52″
Constellation
Leo
Distance from Earth
3.89 AU
Elongation from the Sun
58.69° — near the Sun — look low at dusk or dawn

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
3.047 AU
Eccentricity
0.6918
Inclination
11.38°
Orbital period
5.32 years
Perihelion
0.939 AU
Aphelion
5.155 AU
Longitude of ascending node
69.88°
Argument of periapsis
198.79°
Epoch · J2000
2453856.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 15.8 LD
0.0406 AU
Tisserand (Jupiter)
2.791

Orbit quality

Orbit very uncertain — the object may be effectively lost (uncertainty code 9).

Observations used
31
Data arc
6 days
First observed
2 May 2006
Last observed
8 May 2006
Residual RMS
0.96 ″
Solution · Nick Mastrodemos
2 June 2006

Visual & observation

Absolute magnitude (H)
21.3
Total magnitude M₁ · K₁ 10
21.3

Discovery & classification

Also known as 73P-BN

Near-Earth Object Named

Sources