Comet 17P/Holmes
Comet 17P/Holmes is in the constellation of
Crater,
at a distance of
Finder Charts
View interactive star map
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.
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
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 17P/Holmes from Gloucester, United States (all times relative to the local timezone America/New_York):
- 17P/Holmes is above the horizon from Gloucester, United States.
- Right now it is placed in the East-South-East direction at an altitude of 2.19° above the horizon.
- 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
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.
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:
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.
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 |
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 May 28 | 11h 28m 04s | -12° 01’ 55” | 23.00 | Crater |
| 2025 May 29 | 11h 28m 05s | -12° 00’ 13” | 23.00 | Crater |
| 2025 May 30 | 11h 28m 06s | -11° 58’ 37” | 23.01 | Crater |
| 2025 May 31 | 11h 28m 09s | -11° 57’ 05” | 23.01 | Crater |
| 2025 Jun 01 | 11h 28m 12s | -11° 55’ 38” | 23.02 | Crater |
| 2025 Jun 02 | 11h 28m 16s | -11° 54’ 15” | 23.02 | Crater |
| 2025 Jun 03 | 11h 28m 20s | -11° 52’ 57” | 23.03 | Crater |
| 2025 Jun 04 | 11h 28m 26s | -11° 51’ 44” | 23.03 | Crater |
| 2025 Jun 05 | 11h 28m 32s | -11° 50’ 36” | 23.04 | Crater |
| 2025 Jun 06 | 11h 28m 39s | -11° 49’ 32” | 23.04 | Crater |
| 2025 Jun 07 | 11h 28m 47s | -11° 48’ 33” | 23.04 | Crater |
| 2025 Jun 08 | 11h 28m 55s | -11° 47’ 39” | 23.05 | Crater |
| 2025 Jun 09 | 11h 29m 04s | -11° 46’ 50” | 23.05 | Crater |
| 2025 Jun 10 | 11h 29m 14s | -11° 46’ 06” | 23.06 | Crater |
Additional Resources on TheSkyLive
- Comet 17P/Holmes: Complete reference information on TheSkyLive.com.
- Where is Comet 17P/Holmes?: Key information on locating Comet 17P/Holmes in the sky.
- Distance from Earth: Find out how far Comet 17P/Holmes is from Earth right now.
- How Bright is Comet 17P/Holmes?: Current visual brightness (magnitude) and apparent size.
- Rise and Set Times: Comet 17P/Holmes's rise and set times from your location.
- Interactive Sky Map: planetarium-style interactive visualization of Comet 17P/Holmes's position in the sky.
- Live Position Tracker: high precision position tracker with deep space imagery.
- Ephemeris: 15 days Comet 17P/Holmes's computed ephemeris.
- Orbital elements: information about Comet 17P/Holmes orbital parameters.
- Orbit Visualization. 3d interactive visualization showing the orbit of Comet 17P/Holmes with respect to the major Solar System objects.