Skip to content
Public Universe
Comet

LINEAR

Add to an observing list or journal →

C/1999 K4 (LINEAR)

LINEAR is a comet in the Halley-type comet orbit class. Its orbit takes it from 1.44 AU to 33.09 AU from the Sun; one orbit takes 71.74 years. Orbit from the JPL solution of 15 April 2021.

Where is it now

Distance from Sun
31.9 AU
True anomaly
175.28°
Distance from Earth
31.028 AU
As of
24 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 — 31.9 AU from the Sun LINEAR
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. LINEAR is 31.028 AU from Earth today (4.3 light-hours).

In the sky

Right ascension
03h 55m 28s
Declination
+16° 41′ 04″
Constellation
Taurus
Distance from Earth
31.03 AU
Elongation from the Sun
151.25° — 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
17.265 AU
Eccentricity
0.9165
Inclination
120.77°
Orbital period
71.74 years
Perihelion
1.442 AU
Aphelion
33.088 AU
Longitude of ascending node
241.48°
Argument of periapsis
8.79°
Epoch · J2000
2451318.5
Orbit class · HTC
Halley-type comet
Earth MOID · 169.9 LD
0.4366 AU
Tisserand (Jupiter)
-0.444

Orbit quality

Orbit very uncertain — the object may be effectively lost (uncertainty code 9).

Observations used
18
Data arc
5 days
First observed
17 May 1999
Last observed
22 May 1999
Residual RMS
0.81 ″
Solution · Otto Matic
15 April 2021

Visual & observation

Absolute magnitude (H)
18.5
Total magnitude M₁ · K₁ 10
18.5

Discovery & classification

Also known as 1999 K4

Named

Sources