A/2024 D1
ephemeris	date	magn	radius	delta	ra	dec	elong	phase	PA
Today	18 Dec 2025	20.0	8.159 AU	7.570 AU	09h23m	+69°23'	123.8°	5.7°	245°
Nearest approach	9 Nov 2027	19.1	6.694 AU	5.942 AU	01h20m	+56°35'	136.3°	5.9°	146°
Perihelion	3 Dec 2027	19.1	6.692 AU	6.034 AU	00h55m	+51°57'	128.4°	6.6°	104°

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 displayed light curve is calculated under the assumption that the object remains inactive. (H=10.60; G=.15).

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 A/2024 D1 are:

    e (Eccentricity)                : 0.9995980
    q (Perihelion distance)         : 6.6917520
    i (Inclination)                 : 132.44840
    Ω (Longitude of ascending node) : 179.65570
    ω (Argument of perihelion)      : 125.79240
    L (Longitude of perihelion)     : 222.76444
    B (Latitude of perihelion)      : 36.76465
    T (Time of perihelion passage)  : 2461742.98560

    Epoch                           : 2025 Dec 17
    Reference                       : MPC185658

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

Ephemerides

Date       Time       RA (2000)    DEC (2000)    delta   radius  elong  phase   PA    magn
2025-12-17 00:00 UT   09 24 37.3   +69 13 39     7.582    8.164  123.3    5.8   247   20.0 
2025-12-18 00:00 UT   09 23 21.0   +69 22 18     7.572    8.160  123.8    5.8   245   20.0 
2025-12-18 04:26 UT   09 23 06.6   +69 23 54     7.570    8.159  123.8    5.7   245   20.0 
2025-12-19 00:00 UT   09 22 02.2   +69 30 54     7.563    8.156  124.2    5.7   244   20.0 
2025-12-20 00:00 UT   09 20 41.0   +69 39 25     7.554    8.153  124.6    5.7   242   20.0 
2025-12-21 00:00 UT   09 19 17.4   +69 47 52     7.546    8.149  125.0    5.7   240   20.0 
2025-12-22 00:00 UT   09 17 51.3   +69 56 13     7.537    8.145  125.3    5.7   239   20.0 
2025-12-23 00:00 UT   09 16 22.7   +70 04 30     7.529    8.142  125.7    5.6   237   20.0 
2025-12-24 00:00 UT   09 14 51.6   +70 12 41     7.521    8.138  126.0    5.6   235   20.0 
2025-12-25 00:00 UT   09 13 18.0   +70 20 47     7.513    8.135  126.3    5.6   234   20.0 
2025-12-26 00:00 UT   09 11 41.9   +70 28 46     7.506    8.131  126.6    5.6   232   20.0 
2025-12-27 00:00 UT   09 10 03.3   +70 36 39     7.499    8.128  126.9    5.6   230   20.0 
2025-12-28 00:00 UT   09 08 22.1   +70 44 25     7.492    8.124  127.2    5.5   228   20.0 

    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.