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Comet 38P/Stephan-Oterma

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Comet 38P/Stephan-Oterma Position

Comet 38P/Stephan-Oterma is currently in the constellation of Bootes. The current Right Ascension is 13h 51m 20s and the Declination is +09° 09’ 01”.

13h 51m 20s
+09° 09’ 01”

Simplified sky chart showing where Comet 38P/Stephan-Oterma is right now in the sky with respect to the brightest stars and constellations (see full screen Online Planetarium)

Map showing Comet 38P/Stephan-Oterma in Bootes on March, 29 2020
Field of view: 60x30 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 showing where Comet 38P/Stephan-Oterma is right now (view fullscreen)

RA: 13h 51m 20s
Dec: +09° 09’ 01”
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

The distance of Comet 38P/Stephan-Oterma from Earth is currently 652,114,257 kilometers, equivalent to 4.359115 Astronomical Units. Light takes 36 minutes and 15.2190 seconds to travel from Comet 38P/Stephan-Oterma and arrive to us.

36 minutes and 15.2190 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 0.76572688 Astronomical Units, or 114,551,112 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 22.18.


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: 80.9°
Max altitude: 47.6°
Azimuth: 279.1°
Comet 38P/Stephan-Oterma is above the horizon from Greenwich, United Kingdom

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 17 May 2018 00:00 UTC (JD: 2458256.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.85928470
Orbit inclination i 18.35294296°
Perihelion distance q 1.58849882 AU
237,636,041 km
Aphelion distance Q 20.98898618 AU
3,139,907,647 km
Semi-major axis a 11.28874250 AU
1,688,771,844 km
Orbital period period 37.9300 years
13,853.7318 days
Date of perihelion transit Tp 2018-Nov-10 23:42:18
2,458,433.4877 JD
Next perihelion transit 2056-Oct-15 17:16
2,472,287.2196 JD
Argument of perihelion peri 359.588932376°
Longitude of the ascending node node 78.000471439687°
Mean anomaly M 355.40083647927°
Mean motion n 0.02598578°/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
2020 Mar 22 13h 55m 40s +08° 41’ 09” 22.11 Bootes
2020 Mar 23 13h 55m 08s +08° 44’ 51” 22.12 Bootes
2020 Mar 24 13h 54m 36s +08° 48’ 30” 22.13 Bootes
2020 Mar 25 13h 54m 03s +08° 52’ 06” 22.14 Bootes
2020 Mar 26 13h 53m 30s +08° 55’ 41” 22.15 Bootes
2020 Mar 27 13h 52m 57s +08° 59’ 12” 22.15 Bootes
2020 Mar 28 13h 52m 23s +09° 02’ 39” 22.16 Bootes
2020 Mar 29 13h 51m 50s +09° 06’ 03” 22.17 Bootes
2020 Mar 30 13h 51m 15s +09° 09’ 25” 22.18 Bootes
2020 Mar 31 13h 50m 40s +09° 12’ 42” 22.19 Bootes
2020 Apr 01 13h 50m 06s +09° 15’ 56” 22.19 Bootes
2020 Apr 02 13h 49m 31s +09° 19’ 06” 22.20 Bootes
2020 Apr 03 13h 48m 56s +09° 22’ 13” 22.21 Bootes
2020 Apr 04 13h 48m 20s +09° 25’ 14” 22.22 Bootes