(221) Eos
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	22 Jun 2026	13.3	2.755 AU	3.078 AU	01h55m	+04°07'	62.2°	19.0°
Opposition	31 Oct 2026	11.8	2.855 AU	1.888 AU	02h43m	-01°07'	163.9°	5.5°

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 Eos are:

            e (Eccentricity)                : 0.1008881
            a (Semimajor axis)              : 3.0119012
            i (Inclination)                 : 10.89072
            Ω (Longitude of ascending node) : 141.71100
            ω (Argument of perihelion)      : 192.42897
            M (Mean anomaly)                : 26.70211
            Epoch                           : 2026 Jun 09

            L (Longitude of perihelion)     : 153.92289
            B (Latitude of perihelion)      : -2.33055
            P (Orbital period in years)     : 5.23            
        

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
2026-06-22 00:00 UT   01 55 22.9   +04 07 16     3.078    2.755   62.2   19.0   246   13.3 
2026-06-22 01:18 UT   01 55 27.2   +04 07 29     3.077    2.755   62.2   19.1   246   13.3 
2026-06-23 00:00 UT   01 56 42.5   +04 11 19     3.067    2.755   62.8   19.2   246   13.3 
2026-06-24 00:00 UT   01 58 01.7   +04 15 17     3.056    2.756   63.4   19.3   246   13.3 
2026-06-25 00:00 UT   01 59 20.5   +04 19 09     3.045    2.757   64.1   19.4   246   13.3 
2026-06-26 00:00 UT   02 00 38.8   +04 22 56     3.034    2.757   64.7   19.5   246   13.3 
2026-06-27 00:00 UT   02 01 56.7   +04 26 37     3.023    2.758   65.3   19.6   246   13.3 
2026-06-28 00:00 UT   02 03 14.2   +04 30 13     3.012    2.758   65.9   19.7   246   13.3 
2026-06-29 00:00 UT   02 04 31.2   +04 33 42     3.001    2.759   66.6   19.8   247   13.3 
2026-06-30 00:00 UT   02 05 47.7   +04 37 06     2.990    2.760   67.2   19.8   247   13.3 
2026-07-01 00:00 UT   02 07 03.8   +04 40 25     2.979    2.760   67.8   19.9   247   13.3 
2026-07-02 00:00 UT   02 08 19.3   +04 43 37     2.967    2.761   68.5   20.0   247   13.3 
2026-07-03 00:00 UT   02 09 34.4   +04 46 44     2.956    2.761   69.1   20.1   247   13.3 
2026-07-04 00:00 UT   02 10 49.0   +04 49 45     2.945    2.762   69.7   20.2   247   13.3 
2026-07-05 00:00 UT   02 12 03.1   +04 52 39     2.933    2.763   70.4   20.3   247   13.3 
2026-07-06 00:00 UT   02 13 16.6   +04 55 28     2.922    2.763   71.0   20.4   248   13.3 
2026-07-07 00:00 UT   02 14 29.7   +04 58 10     2.910    2.764   71.7   20.4   248   13.3 
2026-07-08 00:00 UT   02 15 42.1   +05 00 47     2.898    2.765   72.3   20.5   248   13.2 
2026-07-09 00:00 UT   02 16 54.1   +05 03 17     2.887    2.765   73.0   20.6   248   13.2 
2026-07-10 00:00 UT   02 18 05.4   +05 05 41     2.875    2.766   73.6   20.6   248   13.2 
2026-07-11 00:00 UT   02 19 16.2   +05 07 58     2.863    2.767   74.3   20.7   248   13.2 
2026-07-12 00:00 UT   02 20 26.4   +05 10 10     2.852    2.767   74.9   20.8   249   13.2 
2026-07-13 00:00 UT   02 21 36.0   +05 12 14     2.840    2.768   75.6   20.8   249   13.2 
2026-07-14 00:00 UT   02 22 45.0   +05 14 13     2.828    2.768   76.2   20.9   249   13.2 
2026-07-15 00:00 UT   02 23 53.3   +05 16 04     2.816    2.769   76.9   20.9   249   13.2 
2026-07-16 00:00 UT   02 25 01.0   +05 17 50     2.804    2.770   77.6   21.0   249   13.2 
2026-07-17 00:00 UT   02 26 08.1   +05 19 28     2.792    2.770   78.3   21.0   249   13.2 
2026-07-18 00:00 UT   02 27 14.5   +05 21 00     2.780    2.771   78.9   21.1   249   13.2 
2026-07-19 00:00 UT   02 28 20.2   +05 22 25     2.768    2.772   79.6   21.1   250   13.2 

    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.