C/2021 K2 (MASTER) |
ephemeris |
date |
magn |
radius |
delta |
ra |
dec |
elong |
phase |
PA |
Nearest approach | 13 Jul 2021 | 18.7 | 5.480 AU | 4.561 AU | 19h28m | -49°41' | 152.1° | 5.0° | 1° |
Perihelion | 9 Sep 2021 | 18.9 | 5.464 AU | 5.072 AU | 18h25m | -41°03' | 107.7° | 10.1° | 81° |
Today | 12 Jul 2025 | 23.5 | 10.940 AU | 10.720 AU | 17h03m | +51°54' | 99.9° | 5.3° | 147° |
C/2021 K2 (MASTER)- 2025-07-12
astro.vanbuitenen.nl
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 K2 (MASTER) are:
e (Eccentricity) : 1.0004360
q (Perihelion distance) : 5.4635310
i (Inclination) : 100.87130
Ω (Longitude of ascending node) : 282.33800
ω (Argument of perihelion) : 343.27500
L (Longitude of perihelion) : 285.58168
B (Latitude of perihelion) : -16.41626
T (Time of perihelion passage) : 2459466.73150
Epoch : 2025 Jul 11
Reference : MPEC 2022-O01
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 light curve is based on the absolute magnitude and slope parameter as calculated from an MPEC, or the latest values provided by the minor planet center. (8.00 + 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
2025-07-12 00:00 UT 17 03 58.4 +51 54 20 10.717 10.939 99.9 5.3 147 23.5
2025-07-12 05:45 UT 17 03 50.4 +51 54 01 10.720 10.940 99.9 5.3 147 23.5
2025-07-13 00:00 UT 17 03 25.0 +51 52 58 10.727 10.944 99.7 5.3 146 23.5
2025-07-14 00:00 UT 17 02 52.1 +51 51 31 10.736 10.949 99.4 5.3 145 23.5
2025-07-15 00:00 UT 17 02 19.5 +51 49 59 10.746 10.955 99.2 5.3 144 23.6
2025-07-16 00:00 UT 17 01 47.4 +51 48 22 10.755 10.960 98.9 5.3 143 23.6
2025-07-17 00:00 UT 17 01 15.7 +51 46 40 10.765 10.965 98.7 5.3 142 23.6
2025-07-18 00:00 UT 17 00 44.5 +51 44 54 10.775 10.970 98.4 5.3 141 23.6
2025-07-19 00:00 UT 17 00 13.8 +51 43 03 10.785 10.975 98.2 5.3 140 23.6
2025-07-20 00:00 UT 16 59 43.5 +51 41 08 10.795 10.981 97.9 5.3 139 23.6
2025-07-21 00:00 UT 16 59 13.7 +51 39 09 10.804 10.986 97.6 5.3 138 23.6
2025-07-22 00:00 UT 16 58 44.4 +51 37 05 10.814 10.991 97.3 5.3 137 23.6
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.