(397) Vienna
ephemeris	date	magn	radius	delta	ra	dec	elong	phase
Today	28 Dec 2025	14.8	2.741 AU	3.667 AU	17h17m	-18°45'	16.8°	6.0°
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
2025-12-28 00:00 UT   17 17 15.7   -18 45 56     3.667    2.741   16.8    6.0   289   14.8 
2025-12-28 02:49 UT   17 17 28.1   -18 45 55     3.667    2.740   16.9    6.0   289   14.8 
2025-12-29 00:00 UT   17 19 01.7   -18 45 41     3.661    2.738   17.4    6.2   288   14.8 
2025-12-30 00:00 UT   17 20 47.7   -18 45 20     3.654    2.736   18.0    6.4   287   14.8 
2025-12-31 00:00 UT   17 22 33.8   -18 44 54     3.647    2.733   18.6    6.6   287   14.8 
2026-01-01 00:00 UT   17 24 19.9   -18 44 22     3.640    2.731   19.2    6.8   286   14.8 
2026-01-02 00:00 UT   17 26 06.0   -18 43 46     3.633    2.728   19.8    7.0   286   14.8 
2026-01-03 00:00 UT   17 27 52.2   -18 43 03     3.626    2.726   20.4    7.2   285   14.9 
2026-01-04 00:00 UT   17 29 38.3   -18 42 16     3.619    2.723   21.0    7.4   285   14.9 
2026-01-05 00:00 UT   17 31 24.5   -18 41 23     3.611    2.721   21.5    7.6   285   14.9 
2026-01-06 00:00 UT   17 33 10.8   -18 40 24     3.604    2.718   22.1    7.8   284   14.9 
2026-01-07 00:00 UT   17 34 57.0   -18 39 20     3.596    2.716   22.7    8.0   284   14.9 
2026-01-08 00:00 UT   17 36 43.2   -18 38 10     3.588    2.713   23.3    8.3   283   14.9 
2026-01-09 00:00 UT   17 38 29.4   -18 36 55     3.580    2.711   23.9    8.5   283   14.9 
2026-01-10 00:00 UT   17 40 15.6   -18 35 34     3.572    2.708   24.5    8.7   282   14.9 
2026-01-11 00:00 UT   17 42 01.8   -18 34 07     3.564    2.706   25.1    8.9   282   14.9 
2026-01-12 00:00 UT   17 43 47.9   -18 32 35     3.555    2.703   25.7    9.1   282   14.9 
2026-01-13 00:00 UT   17 45 34.1   -18 30 58     3.547    2.700   26.3    9.3   281   14.9 
2026-01-14 00:00 UT   17 47 20.2   -18 29 14     3.538    2.698   26.9    9.5   281   14.9 
2026-01-15 00:00 UT   17 49 06.2   -18 27 25     3.530    2.695   27.5    9.7   281   14.9 
2026-01-16 00:00 UT   17 50 52.2   -18 25 30     3.521    2.693   28.1    9.9   280   14.9 
2026-01-17 00:00 UT   17 52 38.2   -18 23 30     3.512    2.690   28.7   10.1   280   14.9 

    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.