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public  New Richmond, Stati Uniti New Richmond, Stati Uniti  ⓘ
TimezoneAmerica/Chicago
Sunrise: 5:25 
Transit: 13:12 
Sunset: 21:00
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Comets » 

Comet 123P/West-Hartley

Below the horizon.  Rise: 3:05 | Tran: 10:11 | Set: 17:18
Alt: -16.60°   Az: 315.68°   Direction: South-South-West

Comet 123P/West-Hartley is in the constellation of Aries, at a distance of 656,398,805.0 kilometers from Earth. The current Right Ascension is 03h 13m 01s and the Declination is +16° 20’ 14” (apparent coordinates). The estimated magnitude of comet 123P/West-Hartley, computed using JPL Horizons's data, is 21.65).

Finder Charts

The sky charts below show, at different resolutions, the position of comet 123P/West-Hartley in the sky. Click on each chart to access the interactive star map tool.

Star map showing the position of comet 123P/West-Hartley in the constellation of Aries on F, d Y. Field of view: 50x30 degrees. View interactive star map.
Star map showing the position of comet 123P/West-Hartley in the constellation of Aries on F, d Y. Field of view: 15x9 degrees. View in interactive star map.

The following map uses photographic imagery from the Digitized Sky Survey (DSS) to realistically visualize the precise position of comet 123P/West-Hartley against the stars in the background. The horizontal size of the map measures 60 arcminutes. Click on the image to access a more detailed full-screen view.

123P/West-Hartley
RA: 03h 11m 35s
Dec: +16° 14’ 33”
Simplified high-resolution deep sky chart showing the current position of comet 123P/West-Hartley. Field of view: 60 x 40 arcminutes. Go to the dedicated page

Equatorial Coordinates

Apparent

03h 13m 01s
+16° 20’ 14”
09h 03m 01s
12h 16m 02s

J2000

03h 11m 35s
+16° 14’ 33”

Additional Information

Aries
n/a
n/a
n/a
n/a
21.65

The observed values of Magnitude, Coma Diameter and Tail Length are derived from the most recent observation recorded at the Comet Observers Database. The value of Predicted Magnitude comes from the JPL Horizons ephemerides service and, in the case of comets, might be inaccurate given the highly dynamic and unpredictable behavior of these objects. When available, please refer to the Observed Magnitude value and consider the Predicted 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.

Rise and Set Times

The following table lists today's rise, transit and set times of comet 123P/West-Hartley from New Richmond, Stati Uniti (all times relative to the local timezone America/Chicago):

Azimuth: 73.6°
Max altitude: 61.3°
Azimuth: 286.4°

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.

Distance from Earth

The distance of comet 123P/West-Hartley from Earth is currently 656,398,805.0 kilometers, equivalent to 4.3877549990 Astronomical Units. Light takes 36m 29.511s to travel from comet 123P/West-Hartley and arrive to us.

656,398,805.0
4.3877549990
36m 29.511s

The following graph shows the distance of comet 123P/West-Hartley from Earth as a function of time. In the chart the distance is measured in Astronomical Units and the data is sampled with an interval of 1 day.

Chart of the distance of comet 123P/West-Hartley from Earth in Astronomical Units (au)
Note: The values in this chart may not be entirely accurate around the time of closest approach for objects passing very close to Earth at high speed (e.g., Near-Earth Objects).

The value of the distance of 123P/West-Hartley from Earth is also available as a real time updated value in the live position tracker.

Closest Approach to Earth

In the period between January 1, 2000 and December 31, 2099, the closest approach of comet 123P/West-Hartley to Earth happened on Thursday 28 February 2019 at a distance of 1.199581 Astronomical Units, or 179,454,775 kilometers:

Thursday 28 February 2019
179,454,775
1.199581

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

Light Curve

The following chart shows the light curve of comet 123P/West-Hartley, i.e., its apparent magnitude as a function of time. The curve is calculated using the latest ephemerides provided by JPL Horizons. The magnitude data is sampled with the interval of 2 days. Because of this sampling, inaccuracies may occur for objects that have large variations of brightness over a few days. For comets, large discrepancies can arise between the calculated brightness and the observations due to their highly dynamic, and not always precisely predictable, behavior.

Chart of the magnitude of comet 123P/West-Hartley as a function of time

Orbital Elements

The following table lists the orbital elements of comet 123P/West-Hartley at epoch September, 18 2015 00:00 UTC (JD: 2457284.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.44927022
Orbit inclination i 15.35454558°
Perihelion distance q 2.12610687 AU
318,061,062 km
Aphelion distance Q 5.59494602 AU
836,992,012 km
Semi-major axis a 3.86052645 AU
577,526,537 km
Orbital period period 7.5854 years
2,770.5642 days
Date of perihelion transit Tp February 4, 2019
2,458,518.8399 JD
Next perihelion transit September 5, 2026
2,461,289.4041 JD
Argument of perihelion peri 102.91844683507°
Longitude of the ascending node node 46.527373044969°
Mean anomaly M 199.61304892378°
Mean motion n 0.12993743°/day

Orbit Visualization

The following chart is a 3D animated visualization of the orbit of comet 123P/West-Hartley relative to the other major objects in the Solar System. You can access more advanced features using our 3D Solar System Viewer.

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. Apparent celestial coordinates are provided.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
Jun 16 2025 03h 05m 26s +15° 38’ 51” 21.75 Aries
Jun 17 2025 03h 06m 31s +15° 44’ 51” 21.74 Aries
Jun 18 2025 03h 07m 36s +15° 50’ 48” 21.72 Aries
Jun 19 2025 03h 08m 41s +15° 56’ 43” 21.71 Aries
Jun 20 2025 03h 09m 46s +16° 02’ 37” 21.69 Aries
Jun 21 2025 03h 10m 51s +16° 08’ 30” 21.68 Aries
Jun 22 2025 03h 11m 56s +16° 14’ 21” 21.66 Aries
Jun 23 2025 03h 13m 00s +16° 20’ 10” 21.65 Aries
Jun 24 2025 03h 14m 05s +16° 25’ 57” 21.63 Aries
Jun 25 2025 03h 15m 09s +16° 31’ 43” 21.61 Aries
Jun 26 2025 03h 16m 13s +16° 37’ 28” 21.60 Aries
Jun 27 2025 03h 17m 17s +16° 43’ 10” 21.58 Aries
Jun 28 2025 03h 18m 22s +16° 48’ 51” 21.57 Aries
Jun 29 2025 03h 19m 26s +16° 54’ 30” 21.55 Aries

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