Trans-Neptunian object

577578

577578 (2013 GW136)

577578 is a trans-Neptunian object in the Trans-Neptunian object orbit class. Its orbit takes it from 31.32 AU to 63.76 AU from the Sun; one orbit takes 327.8 years. Discovered 9 April 2013 by Outer Solar System Origins Survey. Orbit from the JPL solution of 7 June 2026.

Where is it now

Distance from Sun: 31.354 AU
True anomaly: 354.38°
Distance from Earth: 32.156 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.

Seen from above the ecliptic, north up, to scale. Grid: Earth's orbit in blue. 577578 is 32.156 AU from Earth today (4.5 light-hours).

In the sky

Right ascension: 16h 26m 30s
Declination: -18° 26′ 34″
Constellation: Ophiuchus
Distance from Earth: 32.16 AU
Elongation from the Sun: 35.41° — near the Sun — look low at dusk or dawn

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.

Paste a location

How do I find my coordinates?

Google Maps on a computer

Right-click the spot where you'll be observing.
The first line of the menu is the coordinates, e.g. 51.50722, -0.12758 — click it and they're copied.
Paste them above.

Google Maps on a phone

Press and hold the spot to drop a pin.
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: 47.536 AU
Eccentricity: 0.3412
Inclination: 6.67°
Orbital period: 327.8 years
Perihelion: 31.315 AU
Aphelion: 63.757 AU
Longitude of ascending node: 219.35°
Argument of periapsis: 35.35°
Epoch · J2000: 2461200.5
Orbit class · TNO: Trans-Neptunian object
Earth MOID · 11,793.1 LD: 30.303 AU
Tisserand (Jupiter): 5.753

Orbit quality

Orbit reasonably well determined (uncertainty code 3).

Observations used: 57
Data arc: 12.37 years
First observed: 7 March 2013
Last observed: 20 July 2025
Residual RMS: 0.3 ″
Solution · Otto Matic: 7 June 2026

Visual & observation

Absolute magnitude (H): 7.41

Discovery & classification

Discovered by: Outer Solar System Origins Survey
Discovery date: 9 April 2013
Discovery site: Maunakea

Also known as 2013 GW136

TNO

Sources

visual properties: JPL SBDB (lookup)
orbital elements: JPL SBDB