P/2019 T5 (ATLAS)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	3 Aug 2019	18.6	1.524 AU	2.262 AU	06h30m	+19°40'	33.6°	21.6°	268°
Nearest approach	27 Jan 2020	20.6	2.562 AU	2.031 AU	10h55m	-41°48'	111.6°	20.9°	324°
Today	25 Dec 2025	31.6	12.562 AU	13.418 AU	16h09m	-24°03'	28.4°	2.1°	275°

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. The light curve is based on the absolute magnitude and slope parameter as calculated from an MPEC, or the latest values provided by the minor planet center. (15.0 + 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 P/2019 T5 (ATLAS) are:

    e (Eccentricity)                : 0.8097110
    q (Perihelion distance)         : 1.5241130
    i (Inclination)                 : 33.48560
    Ω (Longitude of ascending node) : 247.61430
    ω (Argument of perihelion)      : 189.63650
    L (Longitude of perihelion)     : 255.67443
    B (Latitude of perihelion)      : -5.29924
    T (Time of perihelion passage)  : 2458699.12310
    P (Orbital period in years)     : 22.67

    Epoch                           : 2025 Nov 12
    Reference                       : MPEC 2021-P47

    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
2025-12-24 00:00 UT   16 09 01.6   -24 03 01    13.425   12.560   27.4    2.1   275   31.6 
2025-12-25 00:00 UT   16 09 20.8   -24 03 38    13.419   12.562   28.3    2.1   275   31.6 
2025-12-25 01:49 UT   16 09 22.2   -24 03 41    13.418   12.562   28.4    2.1   275   31.6 
2025-12-26 00:00 UT   16 09 39.8   -24 04 14    13.413   12.564   29.3    2.2   275   31.6 
2025-12-27 00:00 UT   16 09 58.8   -24 04 50    13.406   12.566   30.2    2.3   275   31.6 
2025-12-28 00:00 UT   16 10 17.5   -24 05 26    13.400   12.569   31.2    2.3   276   31.6 
2025-12-29 00:00 UT   16 10 36.1   -24 06 02    13.393   12.571   32.1    2.4   276   31.6 
2025-12-30 00:00 UT   16 10 54.6   -24 06 37    13.386   12.573   33.1    2.4   276   31.6 
2025-12-31 00:00 UT   16 11 12.9   -24 07 12    13.378   12.575   34.0    2.5   276   31.6 
2026-01-01 00:00 UT   16 11 31.0   -24 07 46    13.371   12.578   34.9    2.6   276   31.6 
2026-01-02 00:00 UT   16 11 48.9   -24 08 20    13.363   12.580   35.9    2.6   276   31.6 
2026-01-03 00:00 UT   16 12 06.7   -24 08 53    13.355   12.582   36.8    2.7   276   31.6 
2026-01-04 00:00 UT   16 12 24.3   -24 09 27    13.347   12.584   37.8    2.7   277   31.6 

    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.