C/2021 A7 (NEOWISE)
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Nearest approach	5 Apr 2021	15.2	2.311 AU	2.135 AU	06h29m	-30°34'	87.1°	25.6°	99°
Perihelion	15 Jul 2021	15.1	1.965 AU	2.811 AU	09h25m	+12°14'	27.4°	13.8°	113°
Today	22 Feb 2025	26.0	11.573 AU	12.200 AU	20h30m	+30°33'	48.8°	3.7°	322°

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.)

The orbital elements of C/2021 A7 (NEOWISE) are:

            e (Eccentricity)                : 0.9989220
            q (Perihelion distance)         : 1.9647990
            i (Inclination)                 : 78.20480
            Ω (Longitude of ascending node) : 154.41920
            ω (Argument of perihelion)      : 355.98990
            L (Longitude of perihelion)     : 153.59819
            B (Latitude of perihelion)      : -3.92529
            T (Time of perihelion passage)  : 2459410.64280
            P (Orbital period in years)     : 77812.44

            Epoch                           : 2025 Feb 19
            Reference                       : MPEC 2022-M88

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

The light curve chart below shows the estimated development of the comet's magnitude. Blue and black dots are visual and photometric CCD observations respectively from COBS or the MPC. The gray curve is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (10.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 9.89 + 5 log[∆] + 10.00 log[r]).

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.
A more printer-friendly version of the same chart can be found further down this page as well.

The following chart shows the current location of the comet in a smaller, upside-down telescopic field of view.

A printable version of the short-term path of the comet in a field of view that is optimized for (~10x50) binoculars and finderscopes.

Ephemerides:

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-02-22 00:00 UT   20 30 20.0   +30 32 26    12.198   11.569   48.7    3.7   323   26.0 
2025-02-22 14:18 UT   20 30 32.9   +30 33 33    12.200   11.573   48.8    3.7   322   26.0 
2025-02-23 00:00 UT   20 30 41.6   +30 34 18    12.202   11.576   48.9    3.7   321   26.0 
2025-02-24 00:00 UT   20 31 03.0   +30 36 13    12.206   11.582   49.1    3.7   320   26.0 
2025-02-25 00:00 UT   20 31 24.3   +30 38 10    12.210   11.589   49.3    3.7   319   26.0 
2025-02-26 00:00 UT   20 31 45.3   +30 40 10    12.214   11.595   49.5    3.7   318   26.0 
2025-02-27 00:00 UT   20 32 06.2   +30 42 13    12.217   11.602   49.7    3.7   317   26.0 
2025-02-28 00:00 UT   20 32 26.8   +30 44 18    12.221   11.608   49.9    3.7   316   26.0 
2025-03-01 00:00 UT   20 32 47.3   +30 46 26    12.224   11.615   50.2    3.8   314   26.0 
2025-03-02 00:00 UT   20 33 07.5   +30 48 36    12.227   11.621   50.4    3.8   313   26.0 
2025-03-03 00:00 UT   20 33 27.5   +30 50 49    12.230   11.628   50.7    3.8   312   26.0 
2025-03-04 00:00 UT   20 33 47.3   +30 53 04    12.233   11.634   51.0    3.8   311   26.0 

    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.