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Comet

SWAN

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C/2023 A2 (SWAN)

SWAN is a comet in the Comet orbit class. Its orbit takes it from 0.95 AU to 1,108.05 AU from the Sun; one orbit takes 13,057.5 years. Orbit from the JPL solution of 12 March 2026.

Where is it now

Distance from Sun
12.682 AU
True anomaly
148.45°
Distance from Earth
12.622 AU
As of
25 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.

Sun Earth — 0.994 AU from the Sun Earth SWAN — 12.682 AU from the Sun SWAN
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. SWAN is 12.622 AU from Earth today (1.7 light-hours).

In the sky

Right ascension
06h 58m 25s
Declination
-47° 12′ 37″
Constellation
Puppis
Distance from Earth
12.62 AU
Elongation from the Sun
91.32° — well clear of the Sun

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
554.499 AU
Eccentricity
0.9983
Inclination
94.71°
Orbital period
13,057.5 years
Perihelion
0.947 AU
Aphelion
1,108.051 AU
Longitude of ascending node
94.47°
Argument of periapsis
142.58°
Epoch · J2000
2460009.5
Orbit class · COM
Comet
Earth MOID · 15.0 LD
0.0385 AU
Tisserand (Jupiter)
-0.09

Orbit quality

Observations used
159
Data arc
77 days
First observed
30 January 2023
Last observed
17 April 2023
Residual RMS
0.5 ″
Solution · Davide Farnocchia
12 March 2026

Visual & observation

Absolute magnitude (H)
12.8
Total magnitude M₁ · K₁ 20.5
12.8

Discovery & classification

Also known as 2023 A2

Named

Sources