C/2012 S1 (ISON) |
ephemeris |
date |
magn |
radius |
delta |
ra |
dec |
elong |
phase |
PA |
Perihelion | 1 Dec 2013 | -9.3 | 0.013 AU | 0.996 AU | 16h32m | -22°08' | 0.5° | 39.8° | 126° |
Nearest approach | 28 Dec 2013 | 7.6 | 0.986 AU | 0.426 AU | 16h59m | +51°55' | 77.8° | 77.2° | 339° |
Today | 15 Jan 2025 | 31.5 | 29.408 AU | 28.467 AU | 07h24m | +37°43' | 162.5° | 0.6° | 161° |
This comet is a sungrazer.
Although it may become very bright at perihelion, this will only be for a very short period very close to the sun.
C/2012 S1 (ISON)- 2025-01-15
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/2012 S1 (ISON) are:
e (Eccentricity) : 1.0002330
q (Perihelion distance) : 0.0132770
i (Inclination) : 63.89100
Ω (Longitude of ascending node) : 295.10960
ω (Argument of perihelion) : 345.92900
L (Longitude of perihelion) : 288.81511
B (Latitude of perihelion) : -12.61010
T (Time of perihelion passage) : 2456628.07350
Epoch : 2022 May 11
Reference : MPEC 2022-H30
Classification(s): : Nearly isotropic; New (a > 10000 AU); Sungrazer
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. (9.50 + 5 log[∆] + 10.00 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 0.30. (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
2025-01-15 00:00 UT 07 24 51.6 +37 43 46 28.463 29.405 162.8 0.6 163 31.5
2025-01-15 14:05 UT 07 24 45.5 +37 43 54 28.467 29.408 162.5 0.6 161 31.5
2025-01-16 00:00 UT 07 24 41.1 +37 43 59 28.470 29.410 162.3 0.6 159 31.5
2025-01-17 00:00 UT 07 24 30.7 +37 44 12 28.478 29.415 161.8 0.6 156 31.5
2025-01-18 00:00 UT 07 24 20.2 +37 44 24 28.486 29.420 161.2 0.6 154 31.5
2025-01-19 00:00 UT 07 24 09.8 +37 44 35 28.494 29.425 160.6 0.6 151 31.5
2025-01-20 00:00 UT 07 23 59.5 +37 44 45 28.503 29.430 160.0 0.7 148 31.5
2025-01-21 00:00 UT 07 23 49.1 +37 44 55 28.512 29.435 159.3 0.7 146 31.5
2025-01-22 00:00 UT 07 23 38.8 +37 45 04 28.521 29.440 158.6 0.7 144 31.5
2025-01-23 00:00 UT 07 23 28.6 +37 45 12 28.530 29.445 157.9 0.7 142 31.5
2025-01-24 00:00 UT 07 23 18.4 +37 45 20 28.540 29.450 157.2 0.7 140 31.5
2025-01-25 00:00 UT 07 23 08.3 +37 45 26 28.550 29.456 156.4 0.8 138 31.5
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.