C/2016 U1 (NEOWISE)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	9 Dec 2016	10.3	0.887 AU	0.744 AU	15h10m	+30°13'	59.8°	73.7°	329°
Perihelion	9 Jan 2017	6.8	0.320 AU	1.173 AU	18h25m	-19°54'	13.8°	47.0°	281°
Today	9 Sep 2026	32.9	25.232 AU	24.680 AU	03h03m	-05°34'	122.3°	1.9°	267°

The interactive orbit chart above shows the comet'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.)

Light curve

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations from COBS. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 11.5 + 5 log[∆] + 10.3 log[r]). An additional green curve is displayed when an increase in apparent brightness is expected due to forward scattering of sunlight, which occurs when a dust-rich comet is located between the Earth and the Sun. (See Marcus 2007)

Charts

The all-sky chart below shows the path of the comet over the same period as the light curve. The comet's current position is marked yellow.

The following chart shows the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Orbital elements

The orbital elements of C/2016 U1 (NEOWISE) are:

    e (Eccentricity)                : 1.0002080
    q (Perihelion distance)         : 0.3199280
    i (Inclination)                 : 46.07620
    Ω (Longitude of ascending node) : 61.77450
    ω (Argument of perihelion)      : 162.55700
    L (Longitude of perihelion)     : 49.47836
    B (Latitude of perihelion)      : 12.46856
    T (Time of perihelion passage)  : 2457763.28640

    Epoch                           : 2026 May 29
    Reference                       : MPC194149

    Classification(s):              : Nearly isotropic; New (a > 10000 AU)

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-09-08 00:00 UT   03 03 23.6   -05 32 13    24.694   25.224  120.7    2.0   266   32.9 
2026-09-09 00:00 UT   03 03 19.4   -05 33 15    24.686   25.229  121.6    1.9   267   32.9 
2026-09-09 19:06 UT   03 03 15.9   -05 34 05    24.680   25.232  122.3    1.9   267   32.9 
2026-09-10 00:00 UT   03 03 15.0   -05 34 18    24.678   25.233  122.5    1.9   267   32.9 
2026-09-11 00:00 UT   03 03 10.5   -05 35 20    24.670   25.238  123.3    1.9   268   32.9 
2026-09-12 00:00 UT   03 03 05.8   -05 36 23    24.662   25.243  124.2    1.9   268   32.9 
2026-09-13 00:00 UT   03 03 01.0   -05 37 25    24.655   25.248  125.1    1.9   269   32.9 
2026-09-14 00:00 UT   03 02 56.0   -05 38 28    24.647   25.253  126.0    1.8   270   32.9 
2026-09-15 00:00 UT   03 02 50.9   -05 39 31    24.640   25.258  126.9    1.8   270   32.9 
2026-09-16 00:00 UT   03 02 45.7   -05 40 33    24.633   25.262  127.8    1.8   271   32.9 
2026-09-17 00:00 UT   03 02 40.3   -05 41 36    24.626   25.267  128.7    1.8   271   32.9 
2026-09-18 00:00 UT   03 02 34.8   -05 42 39    24.620   25.272  129.5    1.8   272   32.9 
2026-09-19 00:00 UT   03 02 29.2   -05 43 41    24.613   25.277  130.4    1.7   273   32.9 

    Terminology:
            
    delta:  distance between comet and earth in AU
    radius: distance between comet 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-comet)    
    phase:  phase angle in degrees (angle sun-comet-earth)        
    AU:     Astronomical Unit (mean distance between earth and sun: 149597870.7 km      
    

Orbital elements usually provided by the MPC (Minor Planet Center).
Observations contributed by observers worldwide, via COBS (Comet Observation Database) or 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.