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Comet 17P/Holmes

Below the horizon.  Rise: 22:07 | Tran: 2:46 | Set: 7:20
Alt: -8.72°   Az: 255.36°   Direction: West-South-West

Comet 17P/Holmes is in the constellation of Corvus, at a distance of 657,489,921.0 kilometers from Earth. The current Right Ascension is 12h 15m 50s and the Declination is -15° 54’ 41” (apparent coordinates). The predicted magnitude of Comet 17P/Holmes is 23.07 (data provided by JPL Horizons).

Finder Charts

Map showing Comet 17P/Holmes in Corvus on February, 12 2025. Field of view: 50x30 degrees
View interactive star map
Sky map showing Comet 17P/Holmes in Corvus on February, 12 2025. Field of view: 15x9 degrees. View in interactive sky chart

High precision deep sky finder chart, 60 arcmin wide, showing where Comet 17P/Holmes is right now. Click on the image to see a more detailed fullscreen tracker view.

17P/Holmes
RA: 12h 14m 32s
Dec: -15° 46’ 18”
Deep sky finder chart for Comet 17P/Holmes. Field of view: 60x40 arcmins. View in deep sky object tracker

Also check out Where is Comet 17P/Holmes?, a page that provides all the information needed to find Comet 17P/Holmes in the sky and additional links to sky charts.

Celestial Coordinates

Apparent

12h 15m 50s
-15° 54’ 41”
05h 35m 52s
17h 51m 42s

J2000

12h 14m 32s
-15° 46’ 18”

Additional Information

Corvus
n/a
n/a
n/a
n/a
23.07

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 17P/Holmes from Greenwich, UK (all times relative to the local timezone Europe/London):

Azimuth: 105.9°
Max altitude: 22.6°
Azimuth: 254.1°
  • 17P/Holmes is below the horizon from Greenwich, UK.
  • Given its current magnitude, 17P/Holmes 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.

Distance from Earth

The distance of Comet 17P/Holmes from Earth is currently 657,489,921.0 kilometers, equivalent to 4.3950486589 Astronomical Units. Light takes 36m 33.150s to travel from Comet 17P/Holmes and arrive to us.

657,489,921.0
4.3950486589
36m 33.150s

The following chart shows the distance of Comet 17P/Holmes 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.

Chart of the distance of Comet 17P/Holmes from Earth in Astronomical Units (au)

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 17P/Holmes from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest Approach

Between 1 January 2000 and 31 December 2099, the closest approach of Comet 17P/Holmes to Earth happens on Thu Aug 20 2048 at a distance of 1.146026 Astronomical Units, or 171,443,013 kilometers:

Thu Aug 20 2048
171,443,013
1.146026

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 17P/Holmes, 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.

Chart of the magnitude of Comet 17P/Holmes as a function of time

Orbital Elements

The following table lists the orbital elements of Comet 17P/Holmes at epoch 18 October 2016 00:00 UTC (JD: 2457680.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.43015482
Orbit inclination i 19.07035853°
Perihelion distance q 2.06632925 AU
309,118,457 km
Aphelion distance Q 5.18591870 AU
775,802,397 km
Semi-major axis a 3.62612398 AU
542,460,427 km
Orbital period period 6.9051 years
2,522.1006 days
Date of perihelion transit Tp 2014-Mar-26 17:17:14
2,456,743.2203 JD
Next perihelion transit 2021-Feb-19 19:42
2,459,265.3209 JD
Argument of perihelion peri 24.738506005017°
Longitude of the ascending node node 326.77381045426°
Mean anomaly M 133.78558143669°
Mean motion n 0.14273816°/day

Orbit Visualization

Orbit Diagram of Comet 17P/Holmes
View Comet 17P/Holmes in the 3D Solar System Simulator

15 Days Ephemeris

The following table lists the ephemerides of Comet 17P/Holmes 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
2025 Feb 05 12h 18m 26s -15° 44’ 16” 23.12 Corvus
2025 Feb 06 12h 18m 07s -15° 45’ 59” 23.12 Corvus
2025 Feb 07 12h 17m 48s -15° 47’ 37” 23.11 Corvus
2025 Feb 08 12h 17m 27s -15° 49’ 09” 23.10 Corvus
2025 Feb 09 12h 17m 06s -15° 50’ 35” 23.09 Corvus
2025 Feb 10 12h 16m 44s -15° 51’ 55” 23.09 Corvus
2025 Feb 11 12h 16m 21s -15° 53’ 09” 23.08 Corvus
2025 Feb 12 12h 15m 58s -15° 54’ 18” 23.07 Corvus
2025 Feb 13 12h 15m 33s -15° 55’ 20” 23.06 Corvus
2025 Feb 14 12h 15m 08s -15° 56’ 17” 23.06 Corvus
2025 Feb 15 12h 14m 43s -15° 57’ 07” 23.05 Corvus
2025 Feb 16 12h 14m 16s -15° 57’ 53” 23.04 Corvus
2025 Feb 17 12h 13m 49s -15° 58’ 31” 23.04 Corvus
2025 Feb 18 12h 13m 22s -15° 59’ 03” 23.03 Corvus

Additional Resources