(85) Io
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	20 Jun 2026	13.4	2.803 AU	3.803 AU	05h36m	+15°42'	8.6°	3.1°
Opposition	22 Jan 2027	12.5	3.102 AU	2.148 AU	08h03m	+02°50'	162.8°	5.4°

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 Io are:

            e (Eccentricity)                : 0.1929890
            a (Semimajor axis)              : 2.6535067
            i (Inclination)                 : 11.95950
            Ω (Longitude of ascending node) : 203.03594
            ω (Argument of perihelion)      : 122.96267
            M (Mean anomaly)                : 93.83602
            Epoch                           : 2026 Jun 09

            L (Longitude of perihelion)     : 146.57513
            B (Latitude of perihelion)      : 10.01250
            P (Orbital period in years)     : 4.32            
        

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.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-06-20 00:00 UT   05 36 16.6   +15 42 07     3.803    2.803    8.6    3.1   206   13.4 
2026-06-20 16:10 UT   05 37 23.9   +15 42 02     3.804    2.804    8.8    3.2   208   13.4 
2026-06-21 00:00 UT   05 37 56.5   +15 41 58     3.804    2.804    8.9    3.2   209   13.4 
2026-06-22 00:00 UT   05 39 36.4   +15 41 44     3.804    2.806    9.2    3.3   212   13.4 
2026-06-23 00:00 UT   05 41 16.1   +15 41 25     3.805    2.808    9.6    3.5   215   13.4 
2026-06-24 00:00 UT   05 42 55.6   +15 41 01     3.806    2.810    9.9    3.6   218   13.4 
2026-06-25 00:00 UT   05 44 35.1   +15 40 32     3.806    2.812   10.3    3.7   220   13.4 
2026-06-26 00:00 UT   05 46 14.3   +15 39 59     3.806    2.814   10.7    3.8   223   13.4 
2026-06-27 00:00 UT   05 47 53.5   +15 39 21     3.806    2.815   11.1    4.0   225   13.4 
2026-06-28 00:00 UT   05 49 32.5   +15 38 38     3.806    2.817   11.5    4.1   227   13.5 
2026-06-29 00:00 UT   05 51 11.3   +15 37 50     3.806    2.819   11.9    4.3   229   13.5 
2026-06-30 00:00 UT   05 52 50.0   +15 36 57     3.805    2.821   12.4    4.4   231   13.5 
2026-07-01 00:00 UT   05 54 28.5   +15 36 00     3.805    2.823   12.8    4.6   232   13.5 
2026-07-02 00:00 UT   05 56 06.8   +15 34 58     3.804    2.824   13.3    4.7   234   13.5 
2026-07-03 00:00 UT   05 57 45.0   +15 33 51     3.803    2.826   13.7    4.9   235   13.5 
2026-07-04 00:00 UT   05 59 23.0   +15 32 40     3.803    2.828   14.2    5.1   237   13.5 
2026-07-05 00:00 UT   06 01 00.8   +15 31 23     3.802    2.830   14.7    5.2   238   13.5 
2026-07-06 00:00 UT   06 02 38.5   +15 30 02     3.800    2.832   15.2    5.4   239   13.5 
2026-07-07 00:00 UT   06 04 16.0   +15 28 37     3.799    2.833   15.6    5.6   241   13.5 
2026-07-08 00:00 UT   06 05 53.2   +15 27 06     3.798    2.835   16.1    5.7   242   13.5 
2026-07-09 00:00 UT   06 07 30.3   +15 25 31     3.796    2.837   16.6    5.9   243   13.6 
2026-07-10 00:00 UT   06 09 07.2   +15 23 52     3.794    2.839   17.1    6.1   244   13.6 
2026-07-11 00:00 UT   06 10 43.9   +15 22 07     3.793    2.841   17.6    6.2   245   13.6 

    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.