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🌎  Observing from: Greenwich, United Kingdom [change]

Comet 38P/Stephan-Oterma

Comet 38P/Stephan-Oterma is currently in the constellation of Libra. The current Right Ascension of Comet 38P/Stephan-Oterma is 15h 31m 49s and the Declination is -09° 23’ 11” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet 38P/Stephan-Oterma is 26.72 (JPL).

Summary of key facts about Comet 38P/Stephan-Oterma [tip: you can also create a Quick Access page for this data if you access it frequently and would like to have a simpler view]:

15h 31m 49s
-09° 23’ 11”
  • 38P/Stephan-Oterma is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the South-South-West direction at an altitude of 26° above the horizon.
  • Given its current magnitude, 38P/Stephan-Oterma is visible only through long exposure photography.
  • See also 38P/Stephan-Oterma rise and set times.
  • Go to interactive sky chart

If you need to access this information frequently for your observations, you can create a simple customized Quick Access page, so that you can easily bookmark it in your browser favorites or add a shortcut to your mobile phones' home screen.

Additional information about Comet 38P/Stephan-Oterma available on TheSkyLive:

Available Resources

Comet 38P/Stephan-Oterma Position and Finder Charts

Below we provide Comet 38P/Stephan-Oterma finder charts showing where the object is right now in the sky with respect to the brightest stars. The first finder chart has a field of view of 50 degrees, while the second one has a field of view of 10 degrees. Click on each finder chart to access a full screen interactive Online Planetarium.

Map showing Comet 38P/Stephan-Oterma in Libra on February, 07 2023
Field of view: 50x30 degrees
View fullscreen
Map showing Comet 38P/Stephan-Oterma in Libra on February, 07 2023
Field of view: 10x6 degrees
View fullscreen
 = visible to the naked eye
 = binocular, brighter than 10th magnitude
= current altitude ≥ 30°   = current altitude < 30°   = below the horizon
Location: Greenwich, United Kingdom [change]

Higher precision deep sky finder chart, 60 arcmin wide, showing where Comet 38P/Stephan-Oterma is right now. Click on the image to see a more detailed fullscreen tracker view.

RA: 15h 31m 49s
Dec: -09° 23’ 11”
Deep sky finder chart for Comet 38P/Stephan-Oterma
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet 38P/Stephan-Oterma?, a page that provides all the information needed to find Comet 38P/Stephan-Oterma in the sky and additional links to sky charts.

Comet 38P/Stephan-Oterma Distance from Earth

The distance of Comet 38P/Stephan-Oterma from Earth is currently 1,681,152,181 kilometers, equivalent to 11.237808 Astronomical Units. Light takes 1 hours, 33 minutes and 27.7201 seconds to travel from Comet 38P/Stephan-Oterma and arrive to us.

1 hours, 33 minutes and 27.7201 seconds

The following chart shows the distance of Comet 38P/Stephan-Oterma from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.

Distance of Comet 38P/Stephan-Oterma from Earth between January 2013 and December 2100

The value of the reported distance might be somewhat inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of 38P/Stephan-Oterma from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet 38P/Stephan-Oterma to Earth

Between January 2013 and December 2100, the closest approach of Comet 38P/Stephan-Oterma to Earth happens on Mon Dec 17 2018 at a distance of 0.765727 Astronomical Units, or 114,551,111 kilometers:

Mon Dec 17 2018

NOTE: values for the closest approach are computed with a sampling interval of 1 day.

Comet 38P/Stephan-Oterma brightness

The current visual magnitude of Comet 38P/Stephan-Oterma is 26.72.


The observed magnitude and coma diameter values are derived from the Comet Observers Database by averaging the values reported in recent observations (more recent than 4 days), when available. The Estimated Magnitude comes from the JPL Horizons ephemerides service and might be inaccurate given the highly dynamic and unpredictable behavior of comets. When available, please refer to the Observed Magnitude value and consider the Estimated Magnitude as a directional indication. We acknowledge with thanks the comet observations from the COBS Comet Observation Database contributed by observers worldwide and used in this table to report recent comet observations.

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet 38P/Stephan-Oterma, according to the most recent ephemerides data. Magnitude data is sampled with a 2 days interval and there might be inaccuracies for objects changing brightness very rapidly during the course of a few days. For comets there could be large discrepancies between the observed and predicted brightness because of their highly dynamic behaviour.

Predicted magnitude of Comet 38P/Stephan-Oterma between January 2013 and December 2100

Comet 38P/Stephan-Oterma rise and set times

Location: Greenwich, United Kingdom [change]
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London

Today's Comet 38P/Stephan-Oterma rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 99.4°
Max altitude: 29.1°
Azimuth: 260.6°

The rise and set times are defined as the time at which the upper limb of Comet 38P/Stephan-Oterma touches the horizon, considering the effect of the atmospheric refraction. As the atmospheric conditions cannot be modeled precisely the times reported here should be considered correct with an approximation of few minutes.

Comet 38P/Stephan-Oterma Orbital Elements

The following table lists the orbital elements of Comet 38P/Stephan-Oterma at epoch 23 May 2018 00:00 UTC (JD: 2458262.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.85928629
Orbit inclination i 18.35294652°
Perihelion distance q 1.58850505 AU
237,636,973 km
Aphelion distance Q 20.98932339 AU
3,139,958,093 km
Semi-major axis a 11.28891422 AU
1,688,797,533 km
Orbital period period 37.9303 years
13,854.0479 days
Date of perihelion transit Tp 2018-Nov-10 23:41:46
2,458,433.4873 JD
Next perihelion transit 2056-Oct-16 00:50
2,472,287.5353 JD
Argument of perihelion peri 359.58867655349°
Longitude of the ascending node node 78.000364192787°
Mean anomaly M 355.55686223202°
Mean motion n 0.02598519°/day

Visualization of Comet 38P/Stephan-Oterma Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 38P/Stephan-Oterma with respect of the Sun and the orbits of the major planets. The position of Comet 38P/Stephan-Oterma and the planets along their orbits in this diagram accurately represents the current configuration of the objects in the Solar System. This is an experimental feature and it requires a WebGL enabled browser. Please provide us feedback!

Orbit Diagram of Comet 38P/Stephan-Oterma
View Comet 38P/Stephan-Oterma in the 3D Solar System Simulator

Comet 38P/Stephan-Oterma 15 Days Ephemeris

The following table lists the ephemerides of Comet 38P/Stephan-Oterma computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 38P/Stephan-Oterma in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2023 Jan 31 15h 31m 01s -09° 24’ 59” 26.73 Libra
2023 Feb 01 15h 31m 09s -09° 24’ 48” 26.72 Libra
2023 Feb 02 15h 31m 17s -09° 24’ 38” 26.72 Libra
2023 Feb 03 15h 31m 23s -09° 24’ 24” 26.72 Libra
2023 Feb 04 15h 31m 30s -09° 24’ 10” 26.72 Libra
2023 Feb 05 15h 31m 36s -09° 23’ 53” 26.72 Libra
2023 Feb 06 15h 31m 41s -09° 23’ 36” 26.72 Libra
2023 Feb 07 15h 31m 47s -09° 23’ 17” 26.72 Libra
2023 Feb 08 15h 31m 53s -09° 22’ 57” 26.72 Libra
2023 Feb 09 15h 31m 58s -09° 22’ 35” 26.72 Libra
2023 Feb 10 15h 32m 02s -09° 22’ 11” 26.72 Libra
2023 Feb 11 15h 32m 06s -09° 21’ 47” 26.72 Libra
2023 Feb 12 15h 32m 09s -09° 21’ 20” 26.72 Libra
2023 Feb 13 15h 32m 13s -09° 20’ 53” 26.72 Libra