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Comet

LINEAR

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309P/LINEAR

Where is it now

Distance from Sun
5.751 AU
True anomaly
147.47°
Distance from Earth
6.743 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 LINEAR — 5.751 AU from the Sun LINEAR
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. LINEAR is 6.743 AU from Earth today (56.1 light-minutes).

In the sky

Right ascension
13h 41m 21s
Declination
-15° 30′ 31″
Constellation
Virgo
Distance from Earth
6.74 AU
Elongation from the Sun
4.75° — too close to the Sun to observe

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
4.447 AU
Eccentricity
0.608
Inclination
17.67°
Orbital period
9.38 years
Perihelion
1.743 AU
Aphelion
7.151 AU
Longitude of ascending node
11.45°
Argument of periapsis
50.8°
Epoch · J2000
2455893.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 314.2 LD
0.8074 AU
Tisserand (Jupiter)
2.569

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
444
Data arc
19.56 years
First observed
31 August 2005
Last observed
25 March 2025
Residual RMS
0.55 ″
Solution · Otto Matic
11 April 2025

Visual & observation

Absolute magnitude (H)
16.2
Total magnitude M₁ · K₁ 6.8
16.2

Discovery & classification

Also known as 309P · 309P/2005 Q4 · 309P/2014 Q4

Named

Close approaches 12 on record

When (UTC) Body Distance Lunar distances Relative speed
2031-11-08 20:31:00 Juptr 1.8822 AU 732.5 LD 10.7 km/s
2053-04-19 07:19:00 Juptr 1.3717 AU 533.8 LD 11.4 km/s
2067-06-20 03:21:00 Juptr 1.9941 AU 776.0 LD 5.4 km/s
2100-05-28 14:38:00 Juptr 1.3326 AU 518.6 LD 6 km/s
2136-02-21 17:52:00 Juptr 0.9234 AU 359.4 LD 10.1 km/s
2150-09-14 18:44:00 Juptr 1.8246 AU 710.1 LD 5.4 km/s
2183-04-12 20:34:00 Juptr 0.9953 AU 387.3 LD 6.6 km/s
2197-12-01 04:28:00 Juptr 1.4789 AU 575.5 LD 9.8 km/s

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

Sources