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Comet

Hill

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420P/Hill

Where is it now

Distance from Sun
7.594 AU
True anomaly
155.94°
Distance from Earth
7.812 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 Hill — 7.594 AU from the Sun Hill
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Hill is 7.812 AU from Earth today (1.1 light-hours).

In the sky

Right ascension
09h 01m 22s
Declination
+06° 21′ 54″
Constellation
Hydra
Distance from Earth
7.8 AU
Elongation from the Sun
74.56° — well clear of the Sun

Visible from both hemispheres.

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
5.513 AU
Eccentricity
0.4943
Inclination
14.46°
Orbital period
12.95 years
Perihelion
2.788 AU
Aphelion
8.238 AU
Longitude of ascending node
174.03°
Argument of periapsis
157.61°
Epoch · J2000
2456870.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 694.3 LD
1.7841 AU
Tisserand (Jupiter)
2.677

Orbit quality

Orbit very well determined (uncertainty code 1).

Observations used
223
Data arc
14.46 years
First observed
16 August 2009
Last observed
31 January 2024
Residual RMS
0.76 ″
Solution · Otto Matic
30 May 2024

Visual & observation

Absolute magnitude (H)
15.4
Total magnitude M₁ · K₁ 4.5
15.4

Discovery & classification

Also known as 420P · 420P/2009 Q1 · 420P/2021 E1

Named

Close approaches 10 on record

When (UTC) Body Distance Lunar distances Relative speed
2036-10-24 10:33:00 Juptr 1.2285 AU 478.1 LD 6.9 km/s
2067-01-05 14:03:00 Satrn 1.817 AU 707.1 LD 3.2 km/s
2148-01-08 06:39:00 Juptr 0.9108 AU 354.5 LD 7.6 km/s
2159-09-12 21:27:00 Juptr 1.5231 AU 592.7 LD 4.8 km/s
2189-07-11 23:18:00 Juptr 1.7108 AU 665.8 LD 6.3 km/s
2191-06-20 17:17:00 Juptr 1.9355 AU 753.2 LD 4.1 km/s

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

Sources