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Comet

Johnson

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48P/Johnson

Where is it now

Distance from Sun
4.053 AU
True anomaly
133.54°
Distance from Earth
4.038 AU
As of
11 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 — 0.998 AU from the Sun Earth Johnson — 4.053 AU from the Sun Johnson
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. Johnson is 4.038 AU from Earth today (33.6 light-minutes).

In the sky

Right ascension
07h 44m 59s
Declination
+19° 08′ 10″
Constellation
Gemini
Distance from Earth
4.03 AU
Elongation from the Sun
84.34° — 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
3.499 AU
Eccentricity
0.4271
Inclination
12.21°
Orbital period
6.54 years
Perihelion
2.005 AU
Aphelion
4.993 AU
Longitude of ascending node
110.13°
Argument of periapsis
216.57°
Epoch · J2000
2458564.5
Orbit class · JFc
Jupiter-family comet (P < 20 y)
Earth MOID · 392.2 LD
1.0078 AU
Tisserand (Jupiter)
2.937

Orbit quality

Orbit very well determined (uncertainty code 0).

Observations used
2,212
Data arc
15.61 years
First observed
9 July 2010
Last observed
15 February 2026
Residual RMS
0.7 ″
Solution · Davide Farnocchia
7 July 2026

Physical properties

Mean radius
2.87 km

Visual & observation

Absolute magnitude (H)
9.1
Total magnitude M₁ · K₁ 16.3
9.1

Discovery & classification

Discovered by
Johnson, Ernest Leonard
Discovery date
25 August 1949
Discovery site
Union Observatory, South Africa

Also known as 48P · 1949 II · 1949d · 1956 V · 1956f · 1963 IV · 1963c · 1970 IV

Named

Close approaches 7 on record

When (UTC) Body Distance Lunar distances Relative speed
2074-04-08 03:05:00 Juptr 0.5456 AU 212.3 LD 3.5 km/s
2134-03-21 16:16:00 Juptr 1.0445 AU 406.5 LD 4.7 km/s
2145-06-26 03:07:00 Juptr 0.857 AU 333.5 LD 4.7 km/s

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

Sources