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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
SunriseRise: 6:35  
clear_day Transit: 12:10  
SunsetSet: 17:45
sunny DaytimeWhat's Visible Now?
Comets » 

Comet 17P/Holmes

Altitude: -22.4°   Azimuth: 53.3°   Direction: North-East

Comet 17P/Holmes is currently in the constellation of Sextans, at a distance of 621,056,745 kilometers from Earth.

Finder chart of 17P/Holmes in Sextans on March,05 2024
Map showing Comet 17P/Holmes in Sextans on March, 05 2024. Field of view: 50x30 degrees
View interactive star map
The current Right Ascension of Comet 17P/Holmes is 10h 34m 42s and the Declination is +02° 41’ 37” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current estimated magnitude of Comet 17P/Holmes is 22.97 (JPL).

10h 34m 42s
+02° 41’ 37”

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.

Today's rise, transit and set times of Comet 17P/Holmes from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

Azimuth: 87.3°
Max altitude: 41.2°
Azimuth: 272.7°
  • 17P/Holmes is below the horizon from Greenwich, United Kingdom edit_location_alt.
  • 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.

Additional Resources

Comet 17P/Holmes Position and Finder Charts

Finder chart of 17P/Holmes
Map showing Comet 17P/Holmes in Sextans on March, 05 2024
Field of view: 10x6 degrees
View fullscreen

Higher 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.

RA: 10h 34m 42s
Dec: +02° 41’ 37”
Deep sky finder chart for Comet 17P/Holmes
Field of view: 60x40 arcmins
View fullscreen

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.

Comet 17P/Holmes Distance from Earth

The distance of Comet 17P/Holmes from Earth is currently 621,056,745 kilometers, equivalent to 4.151508 Astronomical Units. Light takes 34 minutes and 31.6223 seconds to travel from Comet 17P/Holmes and arrive to us.

34 minutes and 31.6223 seconds

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 of Comet 17P/Holmes to Earth

Between 1 January 2013 and 30 December 2100, the closest approach of Comet 17P/Holmes to Earth happens on Thu Aug 20 2048 at a distance of 1.146027 Astronomical Units, or 171,443,241 kilometers:

Thu Aug 20 2048

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

Comet 17P/Holmes Brightness and 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

Comet 17P/Holmes 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 0.43015483
Orbit inclination i 19.07035900°
Perihelion distance q 2.06632924 AU
309,118,456 km
Aphelion distance Q 5.18591871 AU
775,802,399 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 24.738508616339°
Longitude of the ascending node node 326.77380841211°
Mean anomaly M 133.78558112051°
Mean motion n 0.14273816°/day

Visualization of Comet 17P/Holmes Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 17P/Holmes with respect of the Sun and the orbits of the major planets. The position of Comet 17P/Holmes 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 17P/Holmes
View Comet 17P/Holmes in the 3D Solar System Simulator

Comet 17P/Holmes 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. Click on each row of the table to locate Comet 17P/Holmes in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2024 Feb 27 10h 39m 37s +02° 24’ 12” 22.96 Sextans
2024 Feb 28 10h 38m 57s +02° 26’ 26” 22.96 Sextans
2024 Feb 29 10h 38m 18s +02° 28’ 41” 22.96 Sextans
2024 Mar 01 10h 37m 41s +02° 30’ 56” 22.96 Sextans
2024 Mar 02 10h 37m 01s +02° 33’ 14” 22.97 Sextans
2024 Mar 03 10h 36m 23s +02° 35’ 32” 22.97 Sextans
2024 Mar 04 10h 35m 44s +02° 37’ 51” 22.97 Sextans
2024 Mar 05 10h 35m 06s +02° 40’ 11” 22.97 Sextans
2024 Mar 06 10h 34m 27s +02° 42’ 33” 22.97 Sextans
2024 Mar 07 10h 33m 48s +02° 44’ 54” 22.98 Sextans
2024 Mar 08 10h 33m 11s +02° 47’ 16” 22.98 Sextans
2024 Mar 09 10h 32m 34s +02° 49’ 39” 22.98 Sextans
2024 Mar 10 10h 31m 55s +02° 52’ 00” 22.98 Sextans
2024 Mar 11 10h 31m 18s +02° 54’ 24” 22.99 Sextans