C/2019 F2 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	14 Feb 2019	17.5	3.081 AU	2.248 AU	07h22m	+00°14'	141.4°	11.5°	69°
Perihelion	8 Sep 2019	16.9	2.237 AU	3.195 AU	12h03m	+02°35'	15.1°	6.7°	103°
Today	17 Oct 2025	28.2	14.485 AU	13.881 AU	21h58m	-04°05'	125.7°	3.2°	75°

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 10.9 + 5 log[∆] + 10.0 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/2019 F2 (ATLAS) are:

    e (Eccentricity)                : 0.8648610
    q (Perihelion distance)         : 2.2371140
    i (Inclination)                 : 19.34390
    Ω (Longitude of ascending node) : 175.33450
    ω (Argument of perihelion)      : 11.60380
    L (Longitude of perihelion)     : 186.29957
    B (Latitude of perihelion)      : 3.82022
    T (Time of perihelion passage)  : 2458734.54440
    P (Orbital period in years)     : 67.35

    Epoch                           : 2025 Oct 16
    Reference                       : MPC188408

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-10-16 00:00 UT   21 58 45.9   -04 03 29    13.850   14.478  127.4    3.1    76   28.2 
2025-10-17 00:00 UT   21 58 39.6   -04 04 45    13.868   14.482  126.4    3.2    76   28.2 
2025-10-17 17:47 UT   21 58 35.1   -04 05 41    13.881   14.485  125.7    3.2    75   28.2 
2025-10-18 00:00 UT   21 58 33.5   -04 06 01    13.886   14.486  125.4    3.2    75   28.2 
2025-10-19 00:00 UT   21 58 27.7   -04 07 15    13.904   14.490  124.4    3.3    75   28.2 
2025-10-20 00:00 UT   21 58 22.2   -04 08 28    13.922   14.494  123.4    3.3    75   28.2 
2025-10-21 00:00 UT   21 58 16.9   -04 09 40    13.940   14.498  122.4    3.3    75   28.2 
2025-10-22 00:00 UT   21 58 11.9   -04 10 51    13.959   14.502  121.4    3.4    74   28.2 
2025-10-23 00:00 UT   21 58 07.1   -04 12 00    13.978   14.507  120.4    3.4    74   28.2 
2025-10-24 00:00 UT   21 58 02.6   -04 13 09    13.997   14.511  119.4    3.4    74   28.2 
2025-10-25 00:00 UT   21 57 58.4   -04 14 16    14.016   14.515  118.4    3.5    74   28.3 
2025-10-26 00:00 UT   21 57 54.4   -04 15 22    14.035   14.519  117.3    3.5    74   28.3 
2025-10-27 00:00 UT   21 57 50.6   -04 16 26    14.054   14.523  116.3    3.5    74   28.3 

    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.