C/2018 N1 (NEOWISE)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	27 Jul 2018	9.0	1.310 AU	0.306 AU	20h24m	-37°13'	161.9°	13.9°	2°
Perihelion	3 Aug 2018	9.5	1.306 AU	0.397 AU	17h20m	-29°14'	130.2°	36.4°	89°
Today	15 Sep 2025	29.8	19.500 AU	20.381 AU	10h13m	+22°53'	28.0°	1.4°	313°

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.)

The orbital elements of C/2018 N1 (NEOWISE) are:

            e (Eccentricity)                : 0.9974900
            q (Perihelion distance)         : 1.3062340
            i (Inclination)                 : 159.38870
            Ω (Longitude of ascending node) : 292.59000
            ω (Argument of perihelion)      : 354.74820
            L (Longitude of perihelion)     : 297.50734
            B (Latitude of perihelion)      : -1.84650
            T (Time of perihelion passage)  : 2458333.93300
            P (Orbital period in years)     : 11871.92

            Epoch                           : 2023 Sep 24
            Reference                       : MPEC 2022-M21

            Classification(s):              : Nearly isotropic; Returning (a < 10000 AU); External (P > 200 years)
        

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations respectively from COBS or the MPC. The gray curve is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (15.50 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 10.36 + 5 log[∆] + 10.00 log[r]).

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.
A more printer-friendly version of the same chart can be found further down this page as well.

The following chart shows the current location of the comet in a smaller, upside-down telescopic field of view.

A printable version of the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-09-15 00:00 UT   10 13 38.6   +22 54 08    20.383   19.495   27.2    1.4   314   29.8 
2025-09-15 22:59 UT   10 13 47.9   +22 53 29    20.381   19.500   28.0    1.4   313   29.8 
2025-09-16 00:00 UT   10 13 48.3   +22 53 28    20.381   19.500   28.0    1.4   313   29.8 
2025-09-17 00:00 UT   10 13 58.0   +22 52 48    20.378   19.505   28.9    1.4   312   29.8 
2025-09-18 00:00 UT   10 14 07.6   +22 52 09    20.376   19.510   29.8    1.5   311   29.8 
2025-09-19 00:00 UT   10 14 17.1   +22 51 32    20.373   19.516   30.6    1.5   311   29.8 
2025-09-20 00:00 UT   10 14 26.6   +22 50 55    20.370   19.521   31.5    1.5   310   29.8 
2025-09-21 00:00 UT   10 14 35.9   +22 50 19    20.366   19.526   32.4    1.6   309   29.8 
2025-09-22 00:00 UT   10 14 45.2   +22 49 44    20.362   19.531   33.3    1.6   309   29.8 
2025-09-23 00:00 UT   10 14 54.4   +22 49 10    20.359   19.537   34.1    1.7   308   29.8 
2025-09-24 00:00 UT   10 15 03.5   +22 48 37    20.354   19.542   35.0    1.7   308   29.8 
2025-09-25 00:00 UT   10 15 12.4   +22 48 05    20.350   19.547   35.9    1.7   307   29.8 

    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.