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Trans-Neptunian object

2016 ER403

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(2016 ER403)

Where is it now

Distance from Sun
40.102 AU
True anomaly
44.28°
Distance from Earth
40.739 AU
As of
19 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 — 0.996 AU from the Sun Earth 2016 ER403 — 40.102 AU from the Sun 2016 ER403
Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 2016 ER403 is 40.739 AU from Earth today (5.6 light-hours).

In the sky

Right ascension
10h 18m 51s
Declination
-04° 21′ 18″
Constellation
Sextans
Distance from Earth
40.74 AU
Elongation from the Sun
49.74° — near the Sun — look low at dusk or dawn

Visible from both hemispheres.

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
42.898 AU
Eccentricity
0.0863
Inclination
15.85°
Orbital period
281 years
Perihelion
39.197 AU
Aphelion
46.599 AU
Longitude of ascending node
275.27°
Argument of periapsis
198.47°
Epoch · J2000
2457435.5
Orbit class · TNO
Trans-Neptunian object
Earth MOID · 14,872.9 LD
38.2167 AU
Tisserand (Jupiter)
5.625

Orbit quality

Orbit very uncertain — the object may be effectively lost (uncertainty code 8).

Observations used
18
Data arc
52 days
First observed
15 January 2016
Last observed
7 March 2016
Residual RMS
0.09 ″
Solution · Otto Matic
29 October 2025

Visual & observation

Absolute magnitude (H)
9.43

Discovery & classification

TNO

Sources