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Comet

Holmes

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17P/Holmes

Where is it now

Distance from Sun
3.603 AU
True anomaly
245.29°
Distance from Earth
4.47 AU
As of
22 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 — 0.995 AU from the Sun Earth Holmes — 3.603 AU from the Sun Holmes
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Holmes is 4.47 AU from Earth today (37.2 light-minutes).

In the sky

Right ascension
14h 54m 35s
Declination
-32° 36′ 42″
Constellation
Centaurus
Distance from Earth
4.47 AU
Elongation from the Sun
25.84° — 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
3.626 AU
Eccentricity
0.4302
Inclination
19.07°
Orbital period
6.91 years
Perihelion
2.066 AU
Aphelion
5.186 AU
Longitude of ascending node
326.77°
Argument of periapsis
24.74°
Epoch · J2000
2457680.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 417.6 LD
1.073 AU
Tisserand (Jupiter)
2.859

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
2,211
Data arc
12.05 years
First observed
4 January 2011
Last observed
22 January 2023
Residual RMS
0.61 ″
Solution · Davide Farnocchia
10 October 2023

Physical properties

Mean radius
1.71 km

Visual & observation

Absolute magnitude (H)
9.4
Total magnitude M₁ · K₁ 14.8
9.4

Discovery & classification

Discovered by
Holmes, Edwin
Discovery date
7 November 1892
Discovery site
London, England

Also known as 17P · 17P/1892 V1 · 17P/1899 L1 · 17P/1964 O1 · 1892 III · 1892f · 1899 II · 1899d

Named

Close approaches 6 on record

When (UTC) Body Distance Lunar distances Relative speed
2051-04-08 03:15:00 Juptr 0.8584 AU 334.1 LD 6.3 km/s
2087-02-19 17:46:00 Juptr 1.9504 AU 759.0 LD 8.8 km/s
2146-05-03 17:39:00 Juptr 1.28 AU 498.1 LD 4.9 km/s

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

Sources