A/2020 A1
ephemeris date magn radius delta ra dec elong phase PA
Perihelion29 Nov 201921.11.674 AU2.139 AU 12h43m-26°23'49.4°26.6°276°
Nearest approach1 Feb 202019.01.862 AU0.913 AU 09h07m-05°23'157.3°11.8°354°
Today18 Feb 202629.515.989 AU16.452 AU 00h37m+36°58'60.5°3.1°44°
A/2020 A1- 2026-02-18
astro.vanbuitenen.nl


 
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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 displayed light curve is calculated under the assumption that the object remains inactive. (H=17.10; G=.15).



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 A/2020 A1 are:

    e (Eccentricity)                : 0.9342530
    q (Perihelion distance)         : 1.6737640
    i (Inclination)                 : 149.03150
    Ω (Longitude of ascending node) : 119.04770
    ω (Argument of perihelion)      : 302.40750
    L (Longitude of perihelion)     : 172.53375
    B (Latitude of perihelion)      : -25.74884
    T (Time of perihelion passage)  : 2458817.26670
    P (Orbital period in years)     : 128.45

    Epoch                           : 2025 Nov 12
    Reference                       : MPEC 2023-A50

    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
2026-02-17 00:00 UT   00 37 17.4   +36 58 49    16.433   15.984   61.4    3.1    45   29.5 
2026-02-18 00:00 UT   00 37 28.2   +36 58 13    16.450   15.989   60.6    3.1    44   29.5 
2026-02-18 02:22 UT   00 37 29.3   +36 58 09    16.452   15.989   60.5    3.1    44   29.5 
2026-02-19 00:00 UT   00 37 39.2   +36 57 39    16.467   15.993   59.8    3.1    43   29.5 
2026-02-20 00:00 UT   00 37 50.3   +36 57 07    16.484   15.998   59.0    3.0    43   29.5 
2026-02-21 00:00 UT   00 38 01.6   +36 56 37    16.501   16.003   58.2    3.0    42   29.5 
2026-02-22 00:00 UT   00 38 13.0   +36 56 11    16.518   16.007   57.4    3.0    42   29.5 
2026-02-23 00:00 UT   00 38 24.6   +36 55 46    16.534   16.012   56.6    3.0    41   29.5 
2026-02-24 00:00 UT   00 38 36.4   +36 55 24    16.551   16.017   55.8    2.9    40   29.5 
2026-02-25 00:00 UT   00 38 48.3   +36 55 04    16.567   16.021   55.1    2.9    40   29.5 
2026-02-26 00:00 UT   00 39 00.3   +36 54 46    16.583   16.026   54.3    2.9    39   29.5 
2026-02-27 00:00 UT   00 39 12.5   +36 54 31    16.599   16.030   53.5    2.8    38   29.5 
2026-02-28 00:00 UT   00 39 24.7   +36 54 18    16.615   16.035   52.7    2.8    37   29.5 



    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.