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Comet

SWAN

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C/2025 R2 (SWAN)

SWAN is a comet in the Comet orbit class. Its orbit takes it from 0.5 AU to 173.19 AU from the Sun; one orbit takes 809.4 years. Orbit from the JPL solution of 6 July 2026.

Where is it now

Distance from Sun
5.531 AU
True anomaly
145.39°
Distance from Earth
4.786 AU
As of
24 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 — 5.531 AU from the Sun SWAN
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. SWAN is 4.786 AU from Earth today (39.8 light-minutes).

In the sky

Right ascension
04h 58m 15s
Declination
+27° 52′ 37″
Constellation
Taurus
Distance from Earth
4.79 AU
Elongation from the Sun
135.47° — 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
86.847 AU
Eccentricity
0.9942
Inclination
4.47°
Orbital period
809.4 years
Perihelion
0.504 AU
Aphelion
173.19 AU
Longitude of ascending node
335.33°
Argument of periapsis
308.36°
Epoch · J2000
2460991.5
Orbit class · COM
Comet
Earth MOID · 18.6 LD
0.0479 AU
Tisserand (Jupiter)
0.936

Orbit quality

Orbit reasonably well determined (uncertainty code 3).

Observations used
2,441
Data arc
197 days
First observed
13 August 2025
Last observed
26 February 2026
Residual RMS
0.63 ″
Solution · Otto Matic
6 July 2026

Visual & observation

Absolute magnitude (H)
13.9
Total magnitude M₁ · K₁ 9.5
13.9

Discovery & classification

Also known as 2025 R2

Named

Close approaches 1 on record

When (UTC) Body Distance Lunar distances Relative speed
2032-05-11 21:52:00 Urnus 1.3482 AU 524.7 LD 10.7 km/s

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

Sources