Comet 21P/Giacobini-Zinner

Comet 21P/Giacobini-Zinner is currently in the constellation of Crater. The current Right Ascension of Comet 21P/Giacobini-Zinner is 11h 48m 17s and the Declination is -10° 10’ 37” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current estimated magnitude of Comet 21P/Giacobini-Zinner is 23.35 (JPL).

Summary of key facts about Comet 21P/Giacobini-Zinner [tip: you can also create a Quick Access page for this data if you access it frequently and would like to have a simpler view]:

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Additional information about Comet 21P/Giacobini-Zinner available on TheSkyLive:

Available Resources

• Position and finder charts (see also Where is Comet 21P/Giacobini-Zinner?)
• Distance from Earth (see also How far is Comet 21P/Giacobini-Zinner from Earth?)
• Rise and set times (see also When does Comet 21P/Giacobini-Zinner rise and set?)
• Brightness (see also How bright is Comet 21P/Giacobini-Zinner?)
• Orbital elements. Detailed information about Comet 21P/Giacobini-Zinner orbital parameters.
• Interactive orbit visualization. 3d visualization showing the orbit of Comet 21P/Giacobini-Zinner with respect to the major Solar System objects.
• 15 days ephemerides. Table showing celestial coordinates and magnitude of Comet 21P/Giacobini-Zinner for the past and next 7 days.
• Interactive sky chart. An online planetarium application that shows where to locate Comet 21P/Giacobini-Zinner in the sky from your location.
• Live position tracker. A high precision sky chart that uses real deep sky imagery to help locate Comet 21P/Giacobini-Zinner with your telescope or on your astrophotographies.

Higher precision deep sky finder chart, 60 arcmin wide, showing where Comet 21P/Giacobini-Zinner is right now. Click on the image to see a more detailed fullscreen tracker view.

Also check out Where is Comet 21P/Giacobini-Zinner?, a page that provides all the information needed to find Comet 21P/Giacobini-Zinner in the sky and additional links to sky charts.

Comet 21P/Giacobini-Zinner Distance from Earth

The distance of Comet 21P/Giacobini-Zinner from Earth is currently 934,084,668 kilometers, equivalent to 6.243970 Astronomical Units. Light takes 51 minutes and 55.7711 seconds to travel from Comet 21P/Giacobini-Zinner and arrive to us.

The following chart shows the distance of Comet 21P/Giacobini-Zinner 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 21P/Giacobini-Zinner from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest approach of Comet 21P/Giacobini-Zinner to Earth

Between January 2013 and December 2100, the closest approach of Comet 21P/Giacobini-Zinner to Earth happens on Fri Oct 28 2078 at a distance of 0.255555 Astronomical Units, or 38,230,446 kilometers:

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

Comet 21P/Giacobini-Zinner brightness

The current visual magnitude of Comet 21P/Giacobini-Zinner is 23.35.

The observed magnitude and coma diameter values are derived from the Comet Observers Database by averaging the values reported in recent observations (more recent than 4 days), when available. The Estimated Magnitude comes from the JPL Horizons ephemerides service and might be inaccurate given the highly dynamic and unpredictable behavior of comets. When available, please refer to the Observed Magnitude value and consider the Estimated 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.

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet 21P/Giacobini-Zinner, 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.

Comet 21P/Giacobini-Zinner rise and set times

Today's Comet 21P/Giacobini-Zinner rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):

The rise and set times are defined as the time at which the upper limb of Comet 21P/Giacobini-Zinner touches the horizon, considering the effect of the atmospheric refraction. As the atmospheric conditions cannot be modeled precisely the times reported here should be considered correct with an approximation of few minutes.

Visualization of Comet 21P/Giacobini-Zinner Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet 21P/Giacobini-Zinner with respect of the Sun and the orbits of the major planets. The position of Comet 21P/Giacobini-Zinner 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!

Comet 21P/Giacobini-Zinner 15 Days Ephemeris

The following table lists the ephemerides of Comet 21P/Giacobini-Zinner computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet 21P/Giacobini-Zinner in our Online Planetarium at the chosen date.

Date	Right AscensionR.A.	DeclinationDec.	MagnitudeMag	Constellation
2020 Oct 21	11h 43m 38s	-09° 42’ 07”	23.35	Crater
2020 Oct 22	11h 44m 17s	-09° 45’ 56”	23.35	Crater
2020 Oct 23	11h 44m 53s	-09° 49’ 45”	23.35	Crater
2020 Oct 24	11h 45m 32s	-09° 53’ 33”	23.35	Crater
2020 Oct 25	11h 46m 09s	-09° 57’ 20”	23.35	Crater
2020 Oct 26	11h 46m 45s	-10° 01’ 08”	23.35	Crater
2020 Oct 27	11h 47m 21s	-10° 04’ 54”	23.35	Crater
2020 Oct 28	11h 47m 58s	-10° 08’ 39”	23.35	Crater
2020 Oct 29	11h 48m 34s	-10° 12’ 25”	23.35	Crater
2020 Oct 30	11h 49m 09s	-10° 16’ 09”	23.34	Crater
2020 Oct 31	11h 49m 45s	-10° 19’ 54”	23.34	Crater
2020 Nov 01	11h 50m 21s	-10° 23’ 38”	23.34	Crater
2020 Nov 02	11h 50m 56s	-10° 27’ 20”	23.34	Crater
2020 Nov 03	11h 51m 29s	-10° 31’ 01”	23.34	Crater