38P/Stephan-Oterma |
ephemeris |
date |
magn |
radius |
delta |
ra |
dec |
elong |
phase |
PA |
Perihelion | 13 Nov 2018 | 6.8 | 1.579 AU | 0.820 AU | 07h25m | +21°43' | 121.3° | 32.4° | 279° |
Nearest approach | 15 Dec 2018 | 6.9 | 1.631 AU | 0.731 AU | 08h12m | +34°49' | 143.4° | 21.1° | 263° |
Today | 9 May 2025 | 41.6 | 14.333 AU | 13.340 AU | 15h44m | -12°03' | 168.9° | 0.8° | 240° |
38P/Stephan-Oterma- 2025-05-09
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 38P/Stephan-Oterma are:
e (Eccentricity) : 0.8597840
q (Perihelion distance) : 1.5793310
i (Inclination) : 18.41470
Ω (Longitude of ascending node) : 77.86050
ω (Argument of perihelion) : 359.58810
L (Longitude of perihelion) : 77.46969
B (Latitude of perihelion) : -0.13012
T (Time of perihelion passage) : 2458436.30790
P (Orbital period in years) : 37.80
Epoch : 2025 May 08
Reference : MPEC 2024-YC7
Classification(s): : Nearly isotropic; Returning (a < 10000 AU); Halley type (P < 200 years)
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 (3.50 + 5 log[∆] + 30.00 log[r]), whereas the red curve is being recalculated every 6 hours based on the available COBS/MPC observations (currently 1.26 + 5 log[∆] + 30.00 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
2025-05-09 00:00 UT 15 44 49.9 -12 04 08 13.340 14.332 168.7 0.8 241 41.6
2025-05-09 07:27 UT 15 44 45.2 -12 03 54 13.340 14.333 168.9 0.8 240 41.6
2025-05-10 00:00 UT 15 44 34.5 -12 03 21 13.341 14.335 169.4 0.7 238 41.6
2025-05-11 00:00 UT 15 44 19.1 -12 02 35 13.342 14.338 170.1 0.7 233 41.6
2025-05-12 00:00 UT 15 44 03.7 -12 01 48 13.343 14.341 170.8 0.6 228 41.6
2025-05-13 00:00 UT 15 43 48.2 -12 01 03 13.345 14.345 171.3 0.6 223 41.6
2025-05-14 00:00 UT 15 43 32.6 -12 00 17 13.347 14.348 171.8 0.6 217 41.6
2025-05-15 00:00 UT 15 43 17.1 -11 59 33 13.349 14.351 172.1 0.6 210 41.6
2025-05-16 00:00 UT 15 43 01.6 -11 58 48 13.352 14.355 172.4 0.5 202 41.6
2025-05-17 00:00 UT 15 42 46.0 -11 58 05 13.355 14.358 172.5 0.5 195 41.6
2025-05-18 00:00 UT 15 42 30.4 -11 57 21 13.358 14.361 172.4 0.5 187 41.6
2025-05-19 00:00 UT 15 42 14.9 -11 56 38 13.361 14.364 172.2 0.5 179 41.6
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.