C/2018 N2 (ASASSN)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	19 Oct 2019	11.7	3.146 AU	2.229 AU	01h08m	+36°49'	152.3°	8.5°	167°
Perihelion	12 Nov 2019	11.8	3.137 AU	2.340 AU	00h14m	+39°11'	136.9°	12.4°	108°
Today	19 Dec 2025	22.5	16.244 AU	16.583 AU	13h59m	+15°19'	68.2°	3.2°	304°

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 5.4 + 5 log[∆] + 9.1 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/2018 N2 (ASASSN) are:

    e (Eccentricity)                : 1.0020910
    q (Perihelion distance)         : 3.1370350
    i (Inclination)                 : 77.46320
    Ω (Longitude of ascending node) : 24.54490
    ω (Argument of perihelion)      : 25.33810
    L (Longitude of perihelion)     : 30.41336
    B (Latitude of perihelion)      : 24.69293
    T (Time of perihelion passage)  : 2458799.57800

    Epoch                           : 2025 Dec 18
    Reference                       : MPEC 2022-YN2

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-12-18 00:00 UT   13 58 57.5   +15 18 41    16.596   16.236   66.9    3.2   304   22.5 
2025-12-19 00:00 UT   13 59 05.0   +15 18 54    16.588   16.242   67.8    3.2   304   22.5 
2025-12-19 12:12 UT   13 59 08.8   +15 19 01    16.583   16.244   68.2    3.2   304   22.5 
2025-12-20 00:00 UT   13 59 12.3   +15 19 09    16.579   16.247   68.7    3.2   303   22.5 
2025-12-21 00:00 UT   13 59 19.5   +15 19 26    16.570   16.253   69.5    3.3   303   22.5 
2025-12-22 00:00 UT   13 59 26.4   +15 19 45    16.561   16.258   70.4    3.3   302   22.5 
2025-12-23 00:00 UT   13 59 33.1   +15 20 06    16.551   16.263   71.3    3.3   302   22.5 
2025-12-24 00:00 UT   13 59 39.6   +15 20 29    16.542   16.269   72.2    3.3   301   22.5 
2025-12-25 00:00 UT   13 59 45.9   +15 20 53    16.533   16.274   73.1    3.3   301   22.5 
2025-12-26 00:00 UT   13 59 52.0   +15 21 20    16.523   16.280   74.0    3.3   300   22.5 
2025-12-27 00:00 UT   13 59 57.9   +15 21 49    16.514   16.285   74.9    3.3   300   22.5 
2025-12-28 00:00 UT   14 00 03.6   +15 22 19    16.504   16.291   75.8    3.4   300   22.5 
2025-12-29 00:00 UT   14 00 09.0   +15 22 51    16.494   16.296   76.7    3.4   299   22.5 

    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.