C/2023 P1 (Nishimura) |
ephemeris |
date |
magn |
radius |
delta |
ra |
dec |
elong |
phase |
PA |
Nearest approach | 12 Sep 2023 | 3.2 | 0.290 AU | 0.838 AU | 11h11m | +19°00' | 14.8° | 117.6° | 352° |
Perihelion | 17 Sep 2023 | 2.6 | 0.224 AU | 0.927 AU | 12h24m | +07°25' | 12.5° | 104.1° | 67° |
Today | 16 Oct 2025 | 22.2 | 8.794 AU | 9.191 AU | 09h07m | -30°20' | 63.6° | 5.8° | 265° |
Please be aware that cometary behaviour is difficult to predict by nature.
Predictions on this page are based on standard models and the latest observations available to me, and will gradually improve with time.
The ability of comets to either disappoint or pleasantly surprise us, is one of many things that make them so interesting.
C/2023 P1 (Nishimura)- 2025-10-16
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.)
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.
This lightcurve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 8.8 + 5 log[∆] + 9.1 log[r]). An additional green curve is displayed when an increase in apparent brightness is expected due to forward scattering of sunlight, which occurs when a dust-rich comet is located between the Earth and the Sun. (See Marcus 2007)
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 C/2023 P1 (Nishimura) are:
e (Eccentricity) : 0.9960140
q (Perihelion distance) : 0.2241530
i (Inclination) : 132.47910
Ω (Longitude of ascending node) : 66.82050
ω (Argument of perihelion) : 116.23150
L (Longitude of perihelion) : 120.70436
B (Latitude of perihelion) : 41.41974
T (Time of perihelion passage) : 2460205.09170
P (Orbital period in years) : 421.71
Epoch : 2025 Oct 15
Reference : MPEC 2024-MB8
Classification(s): : Nearly isotropic; Returning (a < 10000 AU); External (P > 200 years)
Ephemerides
Date Time RA (2000) DEC (2000) delta radius elong phase PA magn
2025-10-15 00:00 UT 09 07 34.5 -30 11 28 9.195 8.780 62.5 5.8 264 22.2
2025-10-16 00:00 UT 09 07 41.7 -30 16 07 9.193 8.788 63.1 5.8 264 22.2
2025-10-16 20:05 UT 09 07 47.3 -30 20 01 9.191 8.794 63.6 5.8 265 22.2
2025-10-17 00:00 UT 09 07 48.4 -30 20 46 9.191 8.796 63.7 5.8 265 22.2
2025-10-18 00:00 UT 09 07 54.6 -30 25 26 9.189 8.803 64.3 5.9 266 22.2
2025-10-19 00:00 UT 09 08 00.4 -30 30 07 9.186 8.811 64.9 5.9 267 22.2
2025-10-20 00:00 UT 09 08 05.7 -30 34 48 9.184 8.819 65.6 5.9 268 22.2
2025-10-21 00:00 UT 09 08 10.5 -30 39 29 9.181 8.827 66.2 5.9 268 22.2
2025-10-22 00:00 UT 09 08 14.9 -30 44 11 9.178 8.834 66.8 5.9 269 22.2
2025-10-23 00:00 UT 09 08 18.9 -30 48 53 9.176 8.842 67.4 6.0 270 22.2
2025-10-24 00:00 UT 09 08 22.3 -30 53 35 9.173 8.850 68.1 6.0 271 22.2
2025-10-25 00:00 UT 09 08 25.3 -30 58 17 9.170 8.858 68.7 6.0 271 22.2
2025-10-26 00:00 UT 09 08 27.8 -31 02 59 9.167 8.865 69.4 6.0 272 22.2
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.