C/2020 Q1 (Borisov)
ephemeris date magn radius delta ra dec elong phase PA
Perihelion15 Aug 202014.11.319 AU1.537 AU 05h38m+28°32'58.1°40.6°271°
Nearest approach25 Sep 202012.91.451 AU0.726 AU 23h49m+67°53'113.2°39.4°174°
Today13 Jun 202630.116.438 AU15.475 AU 16h34m-08°44'160.8°1.2°141°
C/2020 Q1 (Borisov)- 2026-06-13
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. This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 12.0 + 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 C/2020 Q1 (Borisov) are:

    e (Eccentricity)                : 0.9789870
    q (Perihelion distance)         : 1.3194330
    i (Inclination)                 : 142.88820
    Ω (Longitude of ascending node) : 52.42340
    ω (Argument of perihelion)      : 10.06470
    L (Longitude of perihelion)     : 44.36714
    B (Latitude of perihelion)      : 6.05283
    T (Time of perihelion passage)  : 2459077.29880
    P (Orbital period in years)     : 497.56

    Epoch                           : 2026 May 29
    Reference                       : MPC194169

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-06-12 00:00 UT   16 35 04.5   -08 45 10    15.458   16.428  162.1    1.1   145   30.1 
2026-06-13 00:00 UT   16 34 48.4   -08 44 60    15.467   16.434  161.4    1.1   142   30.1 
2026-06-13 19:40 UT   16 34 35.2   -08 44 52    15.475   16.438  160.8    1.2   141   30.1 
2026-06-14 00:00 UT   16 34 32.3   -08 44 50    15.476   16.439  160.7    1.2   140   30.1 
2026-06-15 00:00 UT   16 34 16.3   -08 44 42    15.486   16.444  159.9    1.2   138   30.1 
2026-06-16 00:00 UT   16 34 00.4   -08 44 34    15.496   16.450  159.2    1.3   136   30.1 
2026-06-17 00:00 UT   16 33 44.6   -08 44 27    15.506   16.455  158.4    1.3   134   30.1 
2026-06-18 00:00 UT   16 33 28.8   -08 44 21    15.516   16.460  157.6    1.3   133   30.1 
2026-06-19 00:00 UT   16 33 13.2   -08 44 17    15.527   16.466  156.7    1.4   131   30.1 
2026-06-20 00:00 UT   16 32 57.6   -08 44 13    15.538   16.471  155.9    1.4   130   30.1 
2026-06-21 00:00 UT   16 32 42.2   -08 44 10    15.549   16.476  155.1    1.5   129   30.1 
2026-06-22 00:00 UT   16 32 26.9   -08 44 08    15.560   16.482  154.2    1.5   127   30.1 
2026-06-23 00:00 UT   16 32 11.6   -08 44 07    15.572   16.487  153.3    1.6   126   30.1 



    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.