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Comet Near-Earth

Westphal

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20D/Westphal

Where is it now

Distance from Sun
21.043 AU
True anomaly
195.68°
Distance from Earth
21.677 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 Westphal — 21.043 AU from the Sun Westphal
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Westphal is 21.677 AU from Earth today (3.0 light-hours).

In the sky

Right ascension
14h 25m 29s
Declination
-54° 15′ 03″
Constellation
Lupus
Distance from Earth
21.68 AU
Elongation from the Sun
49.18° — near the Sun — look low at dusk or dawn

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
15.642 AU
Eccentricity
0.9198
Inclination
40.89°
Orbital period
61.87 years
Perihelion
1.254 AU
Aphelion
30.03 AU
Longitude of ascending node
348.01°
Argument of periapsis
57.08°
Epoch · J2000
2420080.5
Orbit class · HTC
Halley-type comet
Earth MOID · 182.2 LD
0.4683 AU
Tisserand (Jupiter)
1.361

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
201
Data arc
61.11 years
First observed
1 September 1852
Last observed
13 October 1913
Residual RMS
2.03 ″
Solution · M.S.W. Keesey
11 April 2003

Visual & observation

Absolute magnitude (H)
8.8
Total magnitude M₁ · K₁ 10
8.8

Discovery & classification

Discovered by
Westphal
Discovery date
24 July 1852
Discovery site
Gottingen Observatory, Germany

Also known as 20D · 1852 IV · 1913 VI · 1913d · 20D/1852 O1 · 20D/1913 S1

Near-Earth Object Named

Close approaches 1 on record

When (UTC) Body Distance Lunar distances Relative speed
2039-09-15 14:33:00 Juptr 1.0406 AU 405.0 LD 14.2 km/s

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

Sources