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Comet

Shoemaker-Holt

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128P/Shoemaker-Holt 1-B

Where is it now

Distance from Sun
3.144 AU
True anomaly
29.2°
Distance from Earth
2.862 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 Shoemaker-Holt — 3.144 AU from the Sun Shoemaker-Holt
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Shoemaker-Holt is 2.862 AU from Earth today (23.8 light-minutes).

In the sky

Right ascension
07h 33m 36s
Declination
+17° 30′ 04″
Constellation
Gemini
Distance from Earth
2.85 AU
Elongation from the Sun
97.66° — 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
4.489 AU
Eccentricity
0.3213
Inclination
4.36°
Orbital period
9.51 years
Perihelion
3.047 AU
Aphelion
5.931 AU
Longitude of ascending node
214.53°
Argument of periapsis
210.22°
Epoch · J2000
2450726.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 802.1 LD
2.0611 AU
Tisserand (Jupiter)
2.913

Orbit quality

Orbit reasonably well determined (uncertainty code 3).

Observations used
236
Data arc
2.58 years
First observed
16 September 1996
Last observed
16 April 1999
Residual RMS
0.54 ″
Solution · Davide Farnocchia
21 November 2016

Physical properties

Mean radius
2.30 km

Visual & observation

Absolute magnitude (H)
5.6
Total magnitude M₁ · K₁ 19
5.6

Discovery & classification

Also known as 128P-B

Named

Close approaches 8 on record

When (UTC) Body Distance Lunar distances Relative speed
2029-07-05 13:18:00 Jupiter 0.2899 AU 112.8 LD 4.7 km/s
2029-07-05 13:18:00 Juptr 0.2899 AU 112.8 LD 4.7 km/s
2041-09-22 12:05:00 Juptr 1.9242 AU 748.8 LD 7.9 km/s

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

Sources