(136199) Eris
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	18 Sep 2025	18.6	95.551 AU	94.695 AU	01h48m	-00°16'	148.2°	0.3°
Opposition	17 Oct 2025	18.6	95.544 AU	94.564 AU	01h47m	-00°22'	169.3°	0.1°

The interactive orbit chart above shows the body's path through the solar system and its position at the given date. Green and blue lines are shown perpendicular to the ecliptic plane: Green if the path is above the ecliptic plane, blue if it is below. (Left-click and drag to rotate the view; Right-click and drag to move the view; Use scroll wheel to zoom in our out.)

The orbital elements of Eris are:

            e (Eccentricity)                : 0.4356757
            a (Semimajor axis)              : 68.0516301
            i (Inclination)                 : 43.82172
            Ω (Longitude of ascending node) : 36.04599
            ω (Argument of perihelion)      : 150.70976
            M (Mean anomaly)                : 211.04229
            Epoch                           : 2025 May 05

            L (Longitude of perihelion)     : 14.01162
            B (Latitude of perihelion)      : 19.80096
            P (Orbital period in years)     : 561.38            
        

The light curve chart below shows the estimated development of the minor planet's magnitude.

The all-sky chart below shows the path of the minor planet over the same period as the light curve. The current position is marked yellow.

The following chart shows the path of the minor planet in the next few days. The field of view is optimized for (~10x50) binoculars and finderscopes. A more printer-friendly version of the same chart can be found below.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-09-18 00:00 UT   01 48 35.0   +00 16 19    94.695   95.551  148.2    0.3   267   18.6 
2025-09-18 17:19 UT   01 48 33.7   +00 16 28    94.689   95.551  148.9    0.3   267   18.6 
2025-09-19 00:00 UT   01 48 33.2   +00 16 31    94.687   95.551  149.1    0.3   267   18.6 
2025-09-20 00:00 UT   01 48 31.3   +00 16 44    94.679   95.550  150.1    0.3   268   18.6 
2025-09-21 00:00 UT   01 48 29.4   +00 16 56    94.671   95.550  151.0    0.3   269   18.6 
2025-09-22 00:00 UT   01 48 27.4   +00 17 08    94.663   95.550  151.9    0.3   270   18.6 
2025-09-23 00:00 UT   01 48 25.5   +00 17 21    94.656   95.550  152.8    0.3   270   18.6 
2025-09-24 00:00 UT   01 48 23.5   +00 17 33    94.649   95.549  153.7    0.3   271   18.6 
2025-09-25 00:00 UT   01 48 21.5   +00 17 45    94.642   95.549  154.6    0.3   272   18.6 
2025-09-26 00:00 UT   01 48 19.5   +00 17 58    94.636   95.549  155.5    0.2   273   18.6 
2025-09-27 00:00 UT   01 48 17.5   +00 18 10    94.630   95.549  156.3    0.2   274   18.6 
2025-09-28 00:00 UT   01 48 15.4   +00 18 22    94.624   95.548  157.2    0.2   276   18.6 
2025-09-29 00:00 UT   01 48 13.3   +00 18 34    94.618   95.548  158.1    0.2   277   18.6 
2025-09-30 00:00 UT   01 48 11.3   +00 18 47    94.613   95.548  158.9    0.2   278   18.6 
2025-10-01 00:00 UT   01 48 09.2   +00 18 59    94.608   95.548  159.8    0.2   280   18.6 
2025-10-02 00:00 UT   01 48 07.1   +00 19 11    94.603   95.547  160.6    0.2   281   18.6 
2025-10-03 00:00 UT   01 48 04.9   +00 19 23    94.598   95.547  161.4    0.2   283   18.6 
2025-10-04 00:00 UT   01 48 02.8   +00 19 35    94.594   95.547  162.2    0.2   285   18.6 
2025-10-05 00:00 UT   01 48 00.6   +00 19 47    94.590   95.547  163.0    0.2   287   18.6 
2025-10-06 00:00 UT   01 47 58.5   +00 19 59    94.586   95.546  163.8    0.2   289   18.6 
2025-10-07 00:00 UT   01 47 56.3   +00 20 11    94.583   95.546  164.5    0.2   292   18.6 
2025-10-08 00:00 UT   01 47 54.1   +00 20 23    94.580   95.546  165.2    0.2   295   18.6 
2025-10-09 00:00 UT   01 47 51.9   +00 20 34    94.577   95.546  165.9    0.1   297   18.6 
2025-10-10 00:00 UT   01 47 49.7   +00 20 46    94.574   95.545  166.5    0.1   301   18.6 
2025-10-11 00:00 UT   01 47 47.5   +00 20 58    94.572   95.545  167.1    0.1   304   18.6 
2025-10-12 00:00 UT   01 47 45.3   +00 21 09    94.570   95.545  167.6    0.1   308   18.6 
2025-10-13 00:00 UT   01 47 43.1   +00 21 21    94.568   95.545  168.1    0.1   312   18.6 
2025-10-14 00:00 UT   01 47 40.8   +00 21 32    94.567   95.544  168.5    0.1   317   18.6 
2025-10-15 00:00 UT   01 47 38.6   +00 21 43    94.566   95.544  168.8    0.1   322   18.6 
2025-10-16 00:00 UT   01 47 36.3   +00 21 55    94.565   95.544  169.1    0.1   327   18.6 
2025-10-17 00:00 UT   01 47 34.1   +00 22 06    94.565   95.544  169.2    0.1   332   18.6 
2025-10-18 00:00 UT   01 47 31.8   +00 22 17    94.564   95.544  169.3    0.1   337   18.6 

    Terminology:
            
    delta:  distance between minor planet and earth in AU
    radius: distance between minor planet and sun in AU
    magn:   magnitude (brightness) estimate    
    ra:     right ascension in hours (24h = 360deg)
    dec:    declination in degrees
    elong:  elongation in degrees (angle sun-earth-minor planet)    
    phase:  phase angle in degrees (angle sun-minor planet-earth)        
    AU:     Astronomical Unit (mean distance between earth and sun: 149597870.7 km
    

Orbital elements provided by the MPC (Minor Planet Center).
Calculations by a modified version of AAPlus, a C# implementation of the AA+ project by PJ Naughter from the algorithms presented in the book "Astronomical Algorithms" by Jean Meeus.
NGC2000 dso catalog and star labels from VizieR as provided by the Strasbourg astronomical Data Center.
Tycho2 catalog from the ESO archive.