Comet 123P/West-Hartley
Comet 123P/West-Hartley is in the constellation of
Cetus,
at a distance of
View interactive star map
Celestial Coordinates
Apparent
J2000
Additional Information
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
Today's rise, transit and set times of Comet 123P/West-Hartley from Greenwich, UK (all times relative to the local timezone Europe/London):
- 123P/West-Hartley is below the horizon from Greenwich, UK.
- Given its current magnitude, 123P/West-Hartley is visible only through long exposure photography.
- 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.
Finder Charts
High precision deep sky finder chart, 60 arcmin wide, showing where Comet 123P/West-Hartley is right now. Click on the image to see a more detailed fullscreen tracker view.
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.
Distance from Earth
The distance of Comet 123P/West-Hartley from Earth is currently
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.
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
Between 1 January 2013 and 30 December 2100, the closest approach of Comet 123P/West-Hartley to Earth happens on Thu Feb 28 2019 at a distance of 1.199581 Astronomical Units, or 179,454,775 kilometers:
NOTE: values for the closest approach are computed with a sampling interval of 1 day.
Light Curve
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.
Orbital Elements
The following table lists the orbital elements of Comet 123P/West-Hartley at epoch 18 September 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 | 2019-Feb-04 08:09:24 2,458,518.8399 JD |
Next perihelion transit | 2026-Sep-05 21:41 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
View Comet 123P/West-Hartley in the 3D Solar System Simulator
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 |
---|---|---|---|---|
2024 Nov 03 | 00h 50m 51s | -04° 59’ 00” | 22.85 | Cetus |
2024 Nov 04 | 00h 50m 18s | -04° 59’ 39” | 22.84 | Cetus |
2024 Nov 05 | 00h 49m 45s | -05° 00’ 11” | 22.84 | Cetus |
2024 Nov 06 | 00h 49m 13s | -05° 00’ 38” | 22.84 | Cetus |
2024 Nov 07 | 00h 48m 41s | -05° 00’ 59” | 22.84 | Cetus |
2024 Nov 08 | 00h 48m 10s | -05° 01’ 13” | 22.84 | Cetus |
2024 Nov 09 | 00h 47m 40s | -05° 01’ 21” | 22.83 | Cetus |
2024 Nov 10 | 00h 47m 10s | -05° 01’ 23” | 22.83 | Cetus |
2024 Nov 11 | 00h 46m 42s | -05° 01’ 20” | 22.83 | Cetus |
2024 Nov 12 | 00h 46m 13s | -05° 01’ 10” | 22.83 | Cetus |
2024 Nov 13 | 00h 45m 46s | -05° 00’ 54” | 22.83 | Cetus |
2024 Nov 14 | 00h 45m 19s | -05° 00’ 31” | 22.83 | Cetus |
2024 Nov 15 | 00h 44m 53s | -05° 00’ 03” | 22.83 | Cetus |
2024 Nov 16 | 00h 44m 28s | -04° 59’ 28” | 22.83 | Cetus |
Additional Resources
- Position and finder charts (see also Where is Comet 123P/West-Hartley?)
- Distance from Earth (see also How far is Comet 123P/West-Hartley from Earth?)
- When does Comet 123P/West-Hartley rise and set?
- Brightness (see also How bright is Comet 123P/West-Hartley?)
- Orbital elements. Detailed information about Comet 123P/West-Hartley orbital parameters.
- Interactive orbit visualization. 3d visualization showing the orbit of Comet 123P/West-Hartley with respect to the major Solar System objects.
- 15 days ephemerides. Table showing celestial coordinates and magnitude of Comet 123P/West-Hartley for the past and next 7 days.
- Interactive sky chart. An online planetarium application that shows where to locate Comet 123P/West-Hartley in the sky from your location.
- Live position tracker. A high precision sky chart that uses real deep sky imagery to help locate Comet 123P/West-Hartley with your telescope or on your astrophotographies.