C/2021 T2 (Fuls)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Perihelion	8 Jun 2022	17.8	1.242 AU	1.470 AU	03h43m	-30°05'	56.5°	42.9°	203°
Nearest approach	7 Jul 2022	17.4	1.317 AU	1.138 AU	07h11m	-52°27'	75.1°	48.3°	178°
Today	17 May 2026	27.5	12.907 AU	12.346 AU	14h00m	+34°12'	121.8°	3.8°	153°

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 estimated manually by the author. (16.5 + 5 log[∆] + 5.0 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/2021 T2 (Fuls) are:

    e (Eccentricity)                : 1.0004840
    q (Perihelion distance)         : 1.2419160
    i (Inclination)                 : 117.47060
    Ω (Longitude of ascending node) : 223.15950
    ω (Argument of perihelion)      : 263.46610
    L (Longitude of perihelion)     : 147.10355
    B (Latitude of perihelion)      : -61.82199
    T (Time of perihelion passage)  : 2459738.97970

    Epoch                           : 2026 May 17
    Reference                       : MPEC 2026-E44

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2026-05-16 00:00 UT   14 01 31.5   +34 12 21    12.319   12.896  122.8    3.8   155   27.5 
2026-05-17 00:00 UT   14 01 11.2   +34 12 33    12.334   12.902  122.2    3.8   154   27.5 
2026-05-17 19:06 UT   14 00 55.2   +34 12 40    12.346   12.907  121.8    3.8   153   27.5 
2026-05-18 00:00 UT   14 00 51.1   +34 12 42    12.349   12.908  121.6    3.8   153   27.5 
2026-05-19 00:00 UT   14 00 31.1   +34 12 47    12.364   12.915  121.0    3.8   152   27.5 
2026-05-20 00:00 UT   14 00 11.4   +34 12 48    12.380   12.921  120.4    3.9   151   27.5 
2026-05-21 00:00 UT   13 59 51.9   +34 12 45    12.395   12.928  119.8    3.9   150   27.5 
2026-05-22 00:00 UT   13 59 32.6   +34 12 38    12.411   12.934  119.1    3.9   149   27.5 
2026-05-23 00:00 UT   13 59 13.5   +34 12 28    12.427   12.941  118.5    3.9   148   27.5 
2026-05-24 00:00 UT   13 58 54.6   +34 12 13    12.443   12.947  117.8    4.0   147   27.5 
2026-05-25 00:00 UT   13 58 36.0   +34 11 55    12.459   12.954  117.2    4.0   146   27.5 
2026-05-26 00:00 UT   13 58 17.7   +34 11 34    12.475   12.960  116.5    4.0   146   27.5 
2026-05-27 00:00 UT   13 57 59.5   +34 11 09    12.492   12.966  115.9    4.0   145   27.5 

    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.