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Comet

TESS

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C/2018 S2 (TESS)

TESS is a comet in the Halley-type comet orbit class. Its orbit takes it from 5.47 AU to 22.94 AU from the Sun; one orbit takes 53.55 years. Orbit from the JPL solution of 25 August 2022.

Where is it now

Distance from Sun
14.021 AU
True anomaly
126.98°
Distance from Earth
14.037 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 TESS — 14.021 AU from the Sun TESS
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. TESS is 14.037 AU from Earth today (1.9 light-hours).

In the sky

Right ascension
10h 18m 31s
Declination
+65° 04′ 38″
Constellation
Ursa Major
Distance from Earth
14.03 AU
Elongation from the Sun
87.26° — 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
14.206 AU
Eccentricity
0.6149
Inclination
64.22°
Orbital period
53.55 years
Perihelion
5.471 AU
Aphelion
22.942 AU
Longitude of ascending node
85.13°
Argument of periapsis
290.68°
Epoch · J2000
2458219.5
Orbit class · HTC
Halley-type comet
Earth MOID · 1,914.7 LD
4.9199 AU
Tisserand (Jupiter)
1.5

Orbit quality

Orbit reasonably well determined (uncertainty code 4).

Observations used
803
Data arc
585 days
First observed
2 August 2017
Last observed
10 March 2019
Residual RMS
0.16 ″
Solution · Otto Matic
25 August 2022

Visual & observation

Absolute magnitude (H)
6.7
Total magnitude M₁ · K₁ 11
6.7

Discovery & classification

Also known as 2018 S2

Named

Sources