Comet 21P/Giacobini-Zinner

Comet 21P/Giacobini-Zinner is currently in the constellation of Libra.

The current Right Ascension of Comet 21P/Giacobini-Zinner is 15h 02m 23s and the Declination is -05° 35’ 53” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current estimated magnitude of Comet 21P/Giacobini-Zinner is 22.02 (JPL).

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 21P/Giacobini-Zinner from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

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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?)
• 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 759,739,958 kilometers, equivalent to 5.078548 Astronomical Units. Light takes 42 minutes and 14.2197 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 1 January 2013 and 30 December 2100, the closest approach of Comet 21P/Giacobini-Zinner to Earth happens on Fri Oct 28 2078 at a distance of 0.255783 Astronomical Units, or 38,264,665 kilometers:

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

Comet 21P/Giacobini-Zinner Brightness and Light Curve

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.

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
2023 Dec 04	14h 55m 31s	-05° 26’ 12”	22.10	Libra
2023 Dec 05	14h 56m 26s	-05° 27’ 41”	22.09	Libra
2023 Dec 06	14h 57m 20s	-05° 29’ 06”	22.08	Libra
2023 Dec 07	14h 58m 15s	-05° 30’ 28”	22.07	Libra
2023 Dec 08	14h 59m 11s	-05° 31’ 45”	22.06	Libra
2023 Dec 09	15h 00m 05s	-05° 32’ 59”	22.05	Libra
2023 Dec 10	15h 01m 00s	-05° 34’ 10”	22.04	Libra
2023 Dec 11	15h 01m 54s	-05° 35’ 17”	22.03	Libra
2023 Dec 12	15h 02m 48s	-05° 36’ 20”	22.02	Libra
2023 Dec 13	15h 03m 42s	-05° 37’ 19”	22.01	Libra
2023 Dec 14	15h 04m 37s	-05° 38’ 16”	22.00	Libra
2023 Dec 15	15h 05m 31s	-05° 39’ 07”	21.99	Libra
2023 Dec 16	15h 06m 25s	-05° 39’ 55”	21.98	Libra
2023 Dec 17	15h 07m 19s	-05° 40’ 39”	21.97	Libra