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Comet Near-Earth

Kowalski

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C/2011 S2 (Kowalski)

Where is it now

Distance from Sun
25.091 AU
True anomaly
168.89°
Distance from Earth
25.099 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.

Sun Earth — 0.998 AU from the Sun Earth Kowalski — 25.091 AU from the Sun Kowalski
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Kowalski is 25.099 AU from Earth today (3.5 light-hours).

In the sky

Right ascension
19h 12m 47s
Declination
-22° 03′ 25″
Constellation
Sagittarius
Distance from Earth
25.11 AU
Elongation from the Sun
87.78° — 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
16.306 AU
Eccentricity
0.9316
Inclination
17.57°
Orbital period
65.85 years
Perihelion
1.115 AU
Aphelion
31.498 AU
Longitude of ascending node
288.07°
Argument of periapsis
192.19°
Epoch · J2000
2455857.5
Orbit class · HTC
Halley-type comet
Earth MOID · 53.6 LD
0.1378 AU
Tisserand (Jupiter)
1.546

Orbit quality

Orbit reasonably well determined (uncertainty code 4).

Observations used
343
Data arc
180 days
First observed
30 September 2011
Last observed
28 March 2012
Residual RMS
0.67 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
15.6
Total magnitude M₁ · K₁ 4.5
15.6

Discovery & classification

Also known as 2011 S2

Near-Earth Object Named

Sources