A/2021 E4
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Today	23 Oct 2021	20.5	4.897 AU	5.555 AU	11h48m	+21°32'	44.6°	8.2°	315°
Nearest approach	19 Feb 2022	19.7	4.704 AU	3.931 AU	11h42m	+49°42'	137.2°	8.2°	215°
Perihelion	25 Apr 2022	20.2	4.676 AU	4.528 AU	10h03m	+59°23'	92.2°	12.4°	121°

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 A/2021 E4 are:

            e (eccentricity)                : 0.9935160
            q (perihelion distance)         : 4.6759540
            i (inclination)                 : 116.36060
            Ω (Longitude of ascending node) : 171.17320
            ω (Argument of perihelion)      : 48.28350
            L (Longitude of perihelion)     : 144.69681
            B (Latitude of perihelion)      : 41.97675
            T (Time of perihelion passage)  : 2459694.86140

            Epoch                           : 2021 Oct 22
            Reference                       : MPEC 2021-P47

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

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 indicates the expected brightness if this object is a comet (13.50 + 5 log[∆] + 5.00 log[r]), whereas the red curve indicates the expected lightcurve for an asteroid (H=12.80; G=.15).

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.