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Comet

LINEAR

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C/1999 J4 (LINEAR)

LINEAR is a comet in the Comet orbit class. Its orbit takes it from 3.78 AU to 26,365.09 AU from the Sun; one orbit takes 1,513,911.6 years. Orbit from the JPL solution of 15 April 2021.

Where is it now

Distance from Sun
47.01 AU
True anomaly
147.08°
Distance from Earth
46.397 AU
As of
25 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 — 0.994 AU from the Sun Earth LINEAR — 47.01 AU from the Sun LINEAR
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. LINEAR is 46.397 AU from Earth today (6.4 light-hours).

In the sky

Right ascension
03h 46m 15s
Declination
-33° 38′ 11″
Constellation
Fornax
Distance from Earth
46.4 AU
Elongation from the Sun
127.74° — well clear of the Sun

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
13,184.436 AU
Eccentricity
0.9997
Inclination
118.91°
Orbital period
1,513,911.6 years
Perihelion
3.781 AU
Aphelion
26,365.091 AU
Longitude of ascending node
264.48°
Argument of periapsis
95.12°
Epoch · J2000
2451318.5
Orbit class · COM
Comet
Earth MOID · 1,316.6 LD
3.3831 AU
Tisserand (Jupiter)
-1.165

Orbit quality

Observations used
40
Data arc
27 days
First observed
15 May 1999
Last observed
11 June 1999
Residual RMS
0.65 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
8.5
Total magnitude M₁ · K₁ 10
8.5

Discovery & classification

Also known as 1999 J4

Named

Sources