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Comet 123P/West-Hartley

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Comet 123P/West-Hartley Position

Comet 123P/West-Hartley is currently in the constellation of Leo. The current Right Ascension is 11h 44m 51s and the Declination is +10° 18’ 29”.

11h 44m 51s
+10° 18’ 29”

Simplified sky chart showing where Comet 123P/West-Hartley is right now in the sky with respect to the brightest stars and constellations (see fuillscreen Online Planetarium)

Map showing Comet 123P/West-Hartley in Leo on June, 19 2019
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]

Hihgher precision deep sky finder chart showing where Comet 123P/West-Hartley is right now (view fullscreen)

RA: 11h 44m 51s
Dec: +10° 18’ 29”
Deep sky finder chart for Comet 123P/West-Hartley
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet 123P/West-Hartley?, a page that provides all the information needed to find Comet 123P/West-Hartley in the sky and additional links to sky charts.

Comet 123P/West-Hartley Distance

The distance of Comet 123P/West-Hartley from Earth is currently 332,405,072 kilometers, equivalent to 2.221991 Astronomical Units. Light takes 18 minutes and 28.7840 seconds to travel from Comet 123P/West-Hartley and arrive to us.

18 minutes and 28.7840 seconds

The following chart shows the distance of Comet 123P/West-Hartley 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 123P/West-Hartley from Earth between January 2013 and December 2075

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 123P/West-Hartley from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet 123P/West-Hartley to Earth

Between January 2013 and December 2075 the closest approach of Comet 123P/West-Hartley to Earth happens on Thu Feb 28 2019 at a distance of 1.19957992 Astronomical Units, or 179,454,602 kilometers:

Thu Feb 28 2019

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

Comet 123P/West-Hartley brightness

The current visual magnitude of Comet 123P/West-Hartley is 16.66.


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 behvior 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 123P/West-Hartley, 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 123P/West-Hartley between January 2013 and December 2075

Comet 123P/West-Hartley 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 123P/West-Hartley rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

Azimuth: 79.8°
Max altitude: 48.6°
Azimuth: 280.3°
Comet 123P/West-Hartley 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 123P/West-Hartley touches the horizon, consideting the effect of the atmospheric refraction. As the atmoshpere conditions cannot be modeled precisely the times reported here should be considered correct with an approximation of few minutes.

Comet 123P/West-Hartley Orbital Elements

The following table lists the orbital elements of Comet 123P/West-Hartley at epoch 13 April 2015 00:00 UTC (JD: 2457126.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.44930074
Orbit inclination i 15.35366880°
Perihelion distance q 2.12596738 AU
318,040,194 km
Aphelion distance Q 5.59500685 AU
837,001,113 km
Semi-major axis a 3.86048712 AU
577,520,653 km
Orbital period period 7.5900 years
2,770.5219 days
Date of perihelion transit Tp 2011-Jul-05 13:30:26
2,455,748.0628 JD
Next perihelion transit 2019-Feb-04 02:01
2,458,518.5847 JD
Argument of perihelion peri 102.89469486852°
Longitude of the ascending node node 46.538664250476°
Mean anomaly M 179.11332494197°
Mean motion n 0.12993942°/day

Visualization of Comet 123P/West-Hartley Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 123P/West-Hartley with respect of the Sun and the orbits of the major planets. The position of Comet 123P/West-Hartley 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 123P/West-Hartley
View Comet 123P/West-Hartley in the 3D Solar System Simulator

Comet 123P/West-Hartley 15 Days Ephemeris

The following table lists the ephemerides of Comet 123P/West-Hartley computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 123P/West-Hartley in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2019 Jun 12 11h 36m 55s +12° 05’ 31” 16.49 Leo
2019 Jun 13 11h 38m 02s +11° 50’ 13” 16.52 Leo
2019 Jun 14 11h 39m 07s +11° 34’ 56” 16.54 Leo
2019 Jun 15 11h 40m 15s +11° 19’ 41” 16.56 Leo
2019 Jun 16 11h 41m 23s +11° 04’ 26” 16.59 Leo
2019 Jun 17 11h 42m 32s +10° 49’ 12” 16.61 Leo
2019 Jun 18 11h 43m 41s +10° 34’ 00” 16.64 Leo
2019 Jun 19 11h 44m 49s +10° 18’ 47” 16.66 Leo
2019 Jun 20 11h 46m 00s +10° 03’ 38” 16.69 Virgo
2019 Jun 21 11h 47m 11s +09° 48’ 29” 16.71 Virgo
2019 Jun 22 11h 48m 21s +09° 33’ 23” 16.74 Virgo
2019 Jun 23 11h 49m 32s +09° 18’ 16” 16.76 Virgo
2019 Jun 24 11h 50m 44s +09° 03’ 11” 16.79 Virgo
2019 Jun 25 11h 51m 57s +08° 48’ 09” 16.81 Virgo