(397) Vienna
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	26 Apr 2026	14.2	2.427 AU	2.228 AU	20h24m	-07°35'	88.9°	24.5°
Opposition	4 Aug 2026	12.1	2.172 AU	1.204 AU	20h31m	+05°28'	156.4°	10.8°

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 Vienna are:

            e (Eccentricity)                : 0.2473263
            a (Semimajor axis)              : 2.6351384
            i (Inclination)                 : 12.86808
            Ω (Longitude of ascending node) : 227.88372
            ω (Argument of perihelion)      : 139.93528
            M (Mean anomaly)                : 266.13915
            Epoch                           : 2025 Nov 21

            L (Longitude of perihelion)     : 188.53525
            B (Latitude of perihelion)      : 8.24151
            P (Orbital period in years)     : 4.28            
        

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
2026-04-26 00:00 UT   20 24 25.6   -07 35 35     2.228    2.427   88.9   24.5   256   14.2 
2026-04-26 04:49 UT   20 24 38.8   -07 33 31     2.225    2.426   89.0   24.5   256   14.1 
2026-04-27 00:00 UT   20 25 31.1   -07 25 20     2.214    2.424   89.5   24.5   256   14.1 
2026-04-28 00:00 UT   20 26 35.7   -07 15 02     2.199    2.421   90.2   24.6   256   14.1 
2026-04-29 00:00 UT   20 27 39.4   -07 04 41     2.185    2.419   90.8   24.6   256   14.1 
2026-04-30 00:00 UT   20 28 42.3   -06 54 18     2.170    2.416   91.5   24.6   255   14.1 
2026-05-01 00:00 UT   20 29 44.3   -06 43 53     2.156    2.413   92.1   24.7   255   14.1 
2026-05-02 00:00 UT   20 30 45.5   -06 33 26     2.141    2.410   92.8   24.7   255   14.1 
2026-05-03 00:00 UT   20 31 45.7   -06 22 56     2.127    2.408   93.5   24.7   255   14.0 
2026-05-04 00:00 UT   20 32 45.0   -06 12 24     2.112    2.405   94.1   24.7   255   14.0 
2026-05-05 00:00 UT   20 33 43.4   -06 01 49     2.098    2.402   94.8   24.7   254   14.0 
2026-05-06 00:00 UT   20 34 40.8   -05 51 13     2.084    2.400   95.5   24.7   254   14.0 
2026-05-07 00:00 UT   20 35 37.3   -05 40 35     2.069    2.397   96.1   24.7   254   14.0 
2026-05-08 00:00 UT   20 36 32.8   -05 29 55     2.055    2.394   96.8   24.7   254   14.0 
2026-05-09 00:00 UT   20 37 27.3   -05 19 14     2.041    2.392   97.5   24.7   253   13.9 
2026-05-10 00:00 UT   20 38 20.9   -05 08 31     2.027    2.389   98.2   24.7   253   13.9 
2026-05-11 00:00 UT   20 39 13.4   -04 57 46     2.013    2.386   98.8   24.7   253   13.9 
2026-05-12 00:00 UT   20 40 04.8   -04 47 01     1.998    2.384   99.5   24.7   253   13.9 
2026-05-13 00:00 UT   20 40 55.2   -04 36 14     1.984    2.381  100.2   24.7   252   13.9 
2026-05-14 00:00 UT   20 41 44.5   -04 25 26     1.970    2.378  100.9   24.7   252   13.8 
2026-05-15 00:00 UT   20 42 32.8   -04 14 37     1.956    2.376  101.6   24.6   252   13.8 
2026-05-16 00:00 UT   20 43 19.9   -04 03 48     1.943    2.373  102.3   24.6   251   13.8 
2026-05-17 00:00 UT   20 44 05.9   -03 52 58     1.929    2.370  103.0   24.6   251   13.8 
2026-05-18 00:00 UT   20 44 50.7   -03 42 08     1.915    2.368  103.7   24.5   251   13.8 
2026-05-19 00:00 UT   20 45 34.4   -03 31 17     1.901    2.365  104.4   24.5   251   13.8 
2026-05-20 00:00 UT   20 46 17.0   -03 20 26     1.888    2.362  105.1   24.4   250   13.7 
2026-05-21 00:00 UT   20 46 58.3   -03 09 35     1.874    2.360  105.8   24.4   250   13.7 
2026-05-22 00:00 UT   20 47 38.5   -02 58 45     1.860    2.357  106.5   24.3   250   13.7 
2026-05-23 00:00 UT   20 48 17.4   -02 47 55     1.847    2.354  107.2   24.2   249   13.7 
2026-05-24 00:00 UT   20 48 55.1   -02 37 05     1.834    2.352  107.9   24.2   249   13.7 
2026-05-25 00:00 UT   20 49 31.6   -02 26 16     1.820    2.349  108.7   24.1   249   13.6 
2026-05-26 00:00 UT   20 50 06.8   -02 15 27     1.807    2.346  109.4   24.0   248   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.