C/2021 Y1 (ATLAS) |
ephemeris |
date |
magn |
radius |
delta |
ra |
dec |
elong |
phase |
PA |
Nearest approach | 12 Dec 2022 | 14.1 | 2.613 AU | 1.690 AU | 03h59m | +05°40' | 154.5° | 9.4° | 45° |
Perihelion | 30 Apr 2023 | 13.8 | 2.032 AU | 2.514 AU | 04h43m | -24°14' | 50.8° | 22.6° | 137° |
Today | 12 Jul 2025 | 22.6 | 7.976 AU | 7.280 AU | 15h57m | -14°51' | 130.3° | 5.6° | 106° |
C/2021 Y1 (ATLAS)- 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 Y1 (ATLAS) are:
e (Eccentricity) : 1.0015990
q (Perihelion distance) : 2.0324720
i (Inclination) : 77.18670
Ω (Longitude of ascending node) : 244.76660
ω (Argument of perihelion) : 245.84970
L (Longitude of perihelion) : 271.08445
B (Latitude of perihelion) : -62.84220
T (Time of perihelion passage) : 2460065.43990
Epoch : 2025 Jul 11
Reference : MPEC 2024-GJ3
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 is based on the absolute magnitude and slope parameter as calculated from the original MPEC, or the latest values provided by the MPC (7.00 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 8.40 + 5 log[∆] + 10.94 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 15 57 27.5 -14 51 50 7.275 7.974 130.6 5.6 106 22.6
2025-07-12 06:01 UT 15 57 23.3 -14 51 16 7.280 7.976 130.3 5.6 106 22.6
2025-07-13 00:00 UT 15 57 11.0 -14 49 35 7.295 7.981 129.5 5.6 106 22.6
2025-07-14 00:00 UT 15 56 55.0 -14 47 22 7.316 7.989 128.5 5.7 106 22.6
2025-07-15 00:00 UT 15 56 39.5 -14 45 12 7.336 7.996 127.5 5.8 106 22.6
2025-07-16 00:00 UT 15 56 24.5 -14 43 04 7.357 8.004 126.5 5.9 106 22.6
2025-07-17 00:00 UT 15 56 10.0 -14 40 58 7.378 8.011 125.5 5.9 106 22.6
2025-07-18 00:00 UT 15 55 56.0 -14 38 55 7.399 8.018 124.5 6.0 106 22.6
2025-07-19 00:00 UT 15 55 42.6 -14 36 54 7.420 8.026 123.4 6.1 106 22.6
2025-07-20 00:00 UT 15 55 29.6 -14 34 56 7.442 8.033 122.4 6.1 106 22.7
2025-07-21 00:00 UT 15 55 17.2 -14 32 60 7.464 8.041 121.4 6.2 105 22.7
2025-07-22 00:00 UT 15 55 05.4 -14 31 06 7.485 8.048 120.4 6.2 105 22.7
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.