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public Observing fromLocation: Greenwich, United Kingdom edit_location_alt
north SunriseRise: 7:04  
clear_day Transit: 12:47  
SunsetSet: 18:30 south
sunny DaytimeWhat's Visible Now
Comets » 

Comet 103P/Hartley

Altitude: 34.6°   Azimuth: 273.1°   Direction: West

Comet 103P/Hartley is currently in the constellation of Gemini. The current Right Ascension of Comet 103P/Hartley is 06h 50m 33s and the Declination is +28° 10’ 36” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current estimated magnitude of Comet 103P/Hartley is 13.98 (JPL) while the latest observed magnitude is 10.4 (COBS).

06h 50m 33s
+28° 10’ 36”

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 103P/Hartley from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

Azimuth: 62.2°
Max altitude: 66.9°
Azimuth: 298.0°
  • 103P/Hartley is above the horizon from Greenwich, United Kingdom edit_location_alt.
  • Right now it is placed in the West direction at an altitude of 35° above the horizon.
  • Given its current magnitude, 103P/Hartley is visible with the help of a binocular with a 80mm aperture or a small telescope.
  • 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.

Available Resources

Comet 103P/Hartley Position and Finder Charts

Below we provide Comet 103P/Hartley finder charts showing where the object is right now in the sky with respect to the brightest stars. The first finder chart has a field of view of 50 degrees, while the second one has a field of view of 10 degrees. Click on each finder chart to access a full screen interactive Online Planetarium.

Finder chart of 103P/Hartley in Gemini on October,04 2023
Map showing Comet 103P/Hartley in Gemini on October, 04 2023
Field of view: 50x30 degrees
View fullscreen
Finder chart of 103P/Hartley
Map showing Comet 103P/Hartley in Gemini on October, 04 2023
Field of view: 10x6 degrees
View fullscreen

Higher precision deep sky finder chart, 60 arcmin wide, showing where Comet 103P/Hartley is right now. Click on the image to see a more detailed fullscreen tracker view.

RA: 06h 50m 33s
Dec: +28° 10’ 36”
Deep sky finder chart for Comet 103P/Hartley
Field of view: 60x40 arcmins
View fullscreen

Also check out Where is Comet 103P/Hartley?, a page that provides all the information needed to find Comet 103P/Hartley in the sky and additional links to sky charts.

Comet 103P/Hartley Distance from Earth

The distance of Comet 103P/Hartley from Earth is currently 58,235,661 kilometers, equivalent to 0.389281 Astronomical Units. Light takes 3 minutes and 14.2533 seconds to travel from Comet 103P/Hartley and arrive to us.

3 minutes and 14.2533 seconds

The following chart shows the distance of Comet 103P/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.

Chart of the distance of Comet 103P/Hartley 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 103P/Hartley from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest Approach of Comet 103P/Hartley to Earth

Between 1 January 2000 and 31 December 2099, the closest approach of Comet 103P/Hartley to Earth happens on Thu Oct 21 2010 at a distance of 0.120883 Astronomical Units, or 18,083,776 kilometers:

Thu Oct 21 2010

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

Comet 103P/Hartley Brightness and Light Curve

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet 103P/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.

Chart of the magnitude of Comet 103P/Hartley as a function of time

Comet 103P/Hartley 15 Days Ephemeris

The following table lists the ephemerides of Comet 103P/Hartley computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 103P/Hartley in our Online Planetarium at the chosen date.

Date Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2023 Sep 27 06h 06m 02s +34° 24’ 55” 13.98 Auriga
2023 Sep 28 06h 12m 34s +33° 37’ 35” 13.97 Auriga
2023 Sep 29 06h 18m 57s +32° 49’ 05” 13.97 Auriga
2023 Sep 30 06h 25m 09s +31° 59’ 34” 13.97 Auriga
2023 Oct 01 06h 31m 10s +31° 09’ 10” 13.97 Auriga
2023 Oct 02 06h 37m 01s +30° 18’ 01” 13.97 Auriga
2023 Oct 03 06h 42m 42s +29° 26’ 14” 13.98 Gemini
2023 Oct 04 06h 48m 12s +28° 33’ 59” 13.98 Gemini
2023 Oct 05 06h 53m 34s +27° 41’ 20” 13.99 Gemini
2023 Oct 06 06h 58m 45s +26° 48’ 25” 13.99 Gemini
2023 Oct 07 07h 03m 46s +25° 55’ 20” 14.00 Gemini
2023 Oct 08 07h 08m 38s +25° 02’ 12” 14.01 Gemini
2023 Oct 09 07h 13m 21s +24° 09’ 06” 14.02 Gemini
2023 Oct 10 07h 17m 53s +23° 16’ 06” 14.03 Gemini