(101) Helena
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	24 Apr 2024	13.8	2.945 AU	2.549 AU	09h19m	+17°03'	103.1°	19.4°
Opposition	13 May 2025	12.0	2.582 AU	1.595 AU	15h03m	-33°34'	164.4°	6.0°

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 Helena are:

            e (Eccentricity)                : 0.1408899
            a (Semimajor axis)              : 2.5826053
            i (Inclination)                 : 10.19426
            Ω (Longitude of ascending node) : 343.37133
            ω (Argument of perihelion)      : 347.87684
            M (Mean anomaly)                : 181.10075
            Epoch                           : 2024 Mar 31

            L (Longitude of perihelion)     : 331.43402
            B (Latitude of perihelion)      : -2.13015
            P (Orbital period in years)     : 4.15            
        

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
2024-04-24 00:00 UT   09 19 58.6   +17 03 43     2.549    2.945  103.1   19.4   108   13.8 
2024-04-24 19:13 UT   09 20 15.5   +17 00 12     2.559    2.944  102.4   19.5   108   13.8 
2024-04-25 00:00 UT   09 20 19.8   +16 59 20     2.562    2.944  102.2   19.5   108   13.8 
2024-04-26 00:00 UT   09 20 42.1   +16 54 52     2.575    2.944  101.4   19.6   108   13.8 
2024-04-27 00:00 UT   09 21 05.7   +16 50 20     2.589    2.944  100.5   19.6   108   13.8 
2024-04-28 00:00 UT   09 21 30.4   +16 45 44     2.603    2.944   99.7   19.7   108   13.9 
2024-04-29 00:00 UT   09 21 56.3   +16 41 04     2.616    2.944   98.8   19.8   108   13.9 
2024-04-30 00:00 UT   09 22 23.4   +16 36 19     2.630    2.944   98.0   19.8   108   13.9 
2024-05-01 00:00 UT   09 22 51.5   +16 31 31     2.643    2.943   97.1   19.9   108   13.9 
2024-05-02 00:00 UT   09 23 20.8   +16 26 39     2.657    2.943   96.3   19.9   108   13.9 
2024-05-03 00:00 UT   09 23 51.2   +16 21 43     2.671    2.943   95.5   19.9   108   13.9 
2024-05-04 00:00 UT   09 24 22.6   +16 16 43     2.684    2.943   94.6   20.0   108   13.9 
2024-05-05 00:00 UT   09 24 55.1   +16 11 40     2.698    2.943   93.8   20.0   108   13.9 
2024-05-06 00:00 UT   09 25 28.7   +16 06 32     2.712    2.943   93.0   20.0   108   14.0 
2024-05-07 00:00 UT   09 26 03.3   +16 01 20     2.725    2.942   92.2   20.0   108   14.0 
2024-05-08 00:00 UT   09 26 38.9   +15 56 05     2.739    2.942   91.4   20.1   108   14.0 
2024-05-09 00:00 UT   09 27 15.5   +15 50 46     2.753    2.942   90.6   20.1   108   14.0 
2024-05-10 00:00 UT   09 27 53.0   +15 45 23     2.766    2.942   89.8   20.1   108   14.0 
2024-05-11 00:00 UT   09 28 31.6   +15 39 56     2.780    2.941   89.0   20.1   108   14.0 
2024-05-12 00:00 UT   09 29 11.1   +15 34 26     2.794    2.941   88.2   20.1   108   14.0 
2024-05-13 00:00 UT   09 29 51.5   +15 28 52     2.807    2.941   87.4   20.1   108   14.0 
2024-05-14 00:00 UT   09 30 32.8   +15 23 14     2.821    2.941   86.7   20.1   108   14.0 
2024-05-15 00:00 UT   09 31 15.0   +15 17 33     2.835    2.941   85.9   20.1   108   14.0 
2024-05-16 00:00 UT   09 31 58.1   +15 11 48     2.848    2.940   85.1   20.0   108   14.1 
2024-05-17 00:00 UT   09 32 42.1   +15 05 59     2.862    2.940   84.4   20.0   109   14.1 
2024-05-18 00:00 UT   09 33 26.8   +15 00 07     2.875    2.940   83.6   20.0   109   14.1 
2024-05-19 00:00 UT   09 34 12.4   +14 54 12     2.889    2.940   82.8   20.0   109   14.1 
2024-05-20 00:00 UT   09 34 58.9   +14 48 13     2.903    2.939   82.1   19.9   109   14.1 
2024-05-21 00:00 UT   09 35 46.1   +14 42 10     2.916    2.939   81.3   19.9   109   14.1 
2024-05-22 00:00 UT   09 36 34.0   +14 36 04     2.929    2.939   80.6   19.9   109   14.1 
2024-05-23 00:00 UT   09 37 22.8   +14 29 55     2.943    2.939   79.8   19.8   109   14.1 
2024-05-24 00:00 UT   09 38 12.3   +14 23 42     2.956    2.938   79.1   19.8   109   14.1 

    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.