C/2021 A7 (NEOWISE)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	5 Apr 2021	15.2	2.313 AU	2.136 AU	06h29m	-30°36'	87.1°	25.6°	99°
Perihelion	15 Jul 2021	15.1	1.966 AU	2.813 AU	09h25m	+12°16'	27.3°	13.7°	113°
Today	23 Feb 2026	27.1	13.864 AU	14.542 AU	20h41m	+27°42'	45.3°	2.9°	323°

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 9.9 + 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/2021 A7 (NEOWISE) are:

    e (Eccentricity)                : 0.9990510
    q (Perihelion distance)         : 1.9662540
    i (Inclination)                 : 78.24580
    Ω (Longitude of ascending node) : 154.36890
    ω (Argument of perihelion)      : 356.02700
    L (Longitude of perihelion)     : 153.55830
    B (Latitude of perihelion)      : -3.88956
    T (Time of perihelion passage)  : 2459410.71860
    P (Orbital period in years)     : 94310.51

    Epoch                           : 2026 Feb 22
    Reference                       : MPEC 2022-M88

    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
2026-02-22 00:00 UT   20 40 38.4   +27 40 05    14.536   13.855   45.0    2.9   324   27.1 
2026-02-23 00:00 UT   20 40 56.0   +27 41 36    14.540   13.861   45.2    2.9   323   27.1 
2026-02-23 09:14 UT   20 41 02.8   +27 42 11    14.542   13.864   45.3    2.9   323   27.1 
2026-02-24 00:00 UT   20 41 13.6   +27 43 09    14.544   13.867   45.4    2.9   322   27.1 
2026-02-25 00:00 UT   20 41 30.9   +27 44 44    14.548   13.873   45.6    2.9   320   27.1 
2026-02-26 00:00 UT   20 41 48.2   +27 46 21    14.551   13.879   45.8    2.9   319   27.1 
2026-02-27 00:00 UT   20 42 05.3   +27 48 01    14.554   13.885   46.0    2.9   318   27.1 
2026-02-28 00:00 UT   20 42 22.2   +27 49 42    14.557   13.891   46.3    3.0   317   27.1 
2026-03-01 00:00 UT   20 42 39.0   +27 51 26    14.560   13.897   46.5    3.0   315   27.1 
2026-03-02 00:00 UT   20 42 55.6   +27 53 11    14.563   13.903   46.8    3.0   314   27.1 
2026-03-03 00:00 UT   20 43 12.0   +27 54 59    14.565   13.909   47.1    3.0   313   27.1 
2026-03-04 00:00 UT   20 43 28.3   +27 56 49    14.567   13.916   47.4    3.0   312   27.1 
2026-03-05 00:00 UT   20 43 44.4   +27 58 40    14.569   13.922   47.7    3.0   311   27.1 

    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.