C/2021 A1 (Leonard) - DISINTEGRATED |
ephemeris |
date |
magn |
radius |
delta |
ra |
dec |
elong |
phase |
PA |
Nearest approach | 12 Dec 2021 | 2.8 | 0.774 AU | 0.232 AU | 17h10m | -01°17' | 21.9° | 151.6° | 355° |
Perihelion | 3 Jan 2022 | 5.9 | 0.616 AU | 0.922 AU | 21h39m | -35°33' | 37.5° | 76.6° | 99° |
Disintegration | 1 Mar 2022 | 11.1 | 1.283 AU | 1.995 AU | 21h24m | -34°52' | 33.0° | 24.9° | 220° |
Today | 11 Mar 2025 | - | 11.587 AU | 11.334 AU | 16h34m | -08°04' | 102.3° | 4.8° | 276° |
C/2021 A1 (Leonard)- 2025-03-11
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 A1 (Leonard) are:
e (Eccentricity) : 1.0002240
q (Perihelion distance) : 0.6157330
i (Inclination) : 132.75980
Ω (Longitude of ascending node) : 255.91390
ω (Argument of perihelion) : 225.14400
L (Longitude of perihelion) : 221.60632
B (Latitude of perihelion) : -31.36348
T (Time of perihelion passage) : 2459583.19070
Epoch : 2025 Mar 10
Reference : MPEC 2025-A40
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 (8.50 + 5 log[∆] + 10.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 8.36 + 5 log[∆] + 11.04 log[r]). The additional green curve shows the effect of forward scattering, occurring when the comet is between the earth and the sun, for a gas-to-dust light ratio δ90 of 0.10. (See Marcus 2007)
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
2025-03-11 00:00 UT 16 34 05.6 -08 04 59 11.338 11.584 101.9 4.8 276 25.4
2025-03-11 11:20 UT 16 34 03.1 -08 04 08 11.334 11.587 102.3 4.8 276 25.4
2025-03-12 00:00 UT 16 34 00.2 -08 03 11 11.329 11.591 102.9 4.8 275 25.4
2025-03-13 00:00 UT 16 33 54.4 -08 01 22 11.319 11.598 103.9 4.8 275 25.4
2025-03-14 00:00 UT 16 33 48.2 -07 59 33 11.310 11.605 104.9 4.7 275 25.4
2025-03-15 00:00 UT 16 33 41.7 -07 57 43 11.300 11.612 105.8 4.7 275 25.4
2025-03-16 00:00 UT 16 33 34.9 -07 55 53 11.291 11.619 106.8 4.7 274 25.4
2025-03-17 00:00 UT 16 33 27.6 -07 54 02 11.282 11.626 107.8 4.7 274 25.4
2025-03-18 00:00 UT 16 33 20.0 -07 52 10 11.273 11.633 108.8 4.6 274 25.4
2025-03-19 00:00 UT 16 33 12.1 -07 50 18 11.264 11.640 109.8 4.6 274 25.4
2025-03-20 00:00 UT 16 33 03.8 -07 48 25 11.255 11.647 110.8 4.6 273 25.4
2025-03-21 00:00 UT 16 32 55.1 -07 46 32 11.246 11.653 111.8 4.6 273 25.4
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.