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Comet 21P/Giacobini-Zinner

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Comet 21P/Giacobini-Zinner Sky Charts and Coordinates

This is a simplified sky chart, showing where Comet 21P/Giacobini-Zinner is now with respect to the brightest stars and constellations.

More advanced sky charts are available on TheSkyLive for this object: 1) the Online Planetarium which is interactive and allows to select dates and additional objects to visualize; and 2) the Live Position and Data Tracker which provides the highest precision position data and features deep sky imagery from the Digitized Sky Survey.

Comet 21P/Giacobini-Zinner in Ophiucus on December, 12 2017
High Precision Live Sky Chart
16h 09m 24s
-03° 55’ 32”
20.92
 = visible to the naked eye
 = binocular, brighter than 10th magnitude
= current altitude ≥ 30°   = current altitude < 30°   = below the horizon
Location: Greenwich, United Kingdom [change]

Comet 21P/Giacobini-Zinner Rise and Set Times

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

Azimuth: 93.9°
Max altitude: 34.6°
Azimuth: 266.1°

Comet 21P/Giacobini-Zinner Orbit Diagram

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!

Orbit Diagram of Comet 21P/Giacobini-Zinner
View Comet 21P/Giacobini-Zinner in the 3D Solar System Simulator

Comet 21P/Giacobini-Zinner 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 MagnitudeMag Right AscensionR.A. DeclinationDec. Constellation
2017 Dec 05 21.06 15h 59m 44s -03° 47’ 59” Libra
2017 Dec 06 21.04 16h 01m 05s -03° 49’ 19” Libra
2017 Dec 07 21.02 16h 02m 29s -03° 50’ 34” Ophiucus
2017 Dec 08 21.00 16h 03m 51s -03° 51’ 43” Ophiucus
2017 Dec 09 20.98 16h 05m 13s -03° 52’ 49” Ophiucus
2017 Dec 10 20.96 16h 06m 37s -03° 53’ 48” Ophiucus
2017 Dec 11 20.94 16h 08m 00s -03° 54’ 43” Ophiucus
2017 Dec 12 20.92 16h 09m 24s -03° 55’ 32” Ophiucus
2017 Dec 13 20.89 16h 10m 47s -03° 56’ 17” Ophiucus
2017 Dec 14 20.87 16h 12m 11s -03° 56’ 56” Ophiucus
2017 Dec 15 20.85 16h 13m 36s -03° 57’ 29” Ophiucus
2017 Dec 16 20.83 16h 15m 01s -03° 57’ 56” Ophiucus
2017 Dec 17 20.80 16h 16m 26s -03° 58’ 18” Ophiucus
2017 Dec 18 20.78 16h 17m 50s -03° 58’ 36” Ophiucus

Distance of Comet 21P/Giacobini-Zinner from Earth

The following chart shows the distance of Comet 21P/Giacobini-Zinner from Earth as a function of time. Distance data is measured in Astronomical Units and sampled with a 2 days interval.

The reported distances might be inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of 21P/Giacobini-Zinner is also available as a real time updated value in the Live Position and Data Tracker.

Distance of Comet 21P/Giacobini-Zinner from Earth between January 2013 and December 2075

Light Curve of Comet 21P/Giacobini-Zinner

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.

Predicted magnitude of Comet 21P/Giacobini-Zinner between January 2013 and December 2075

Comet 21P/Giacobini-Zinner Orbital Elements

The following table lists the orbital elements of Comet 21P/Giacobini-Zinner at epoch 24 July 2013 00:00 UTC (JD: 2456498.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.70681789
Orbit inclination i 31.90810099°
Perihelion distance q 1.03069627 AU
154,189,968 km
Aphelion distance Q 6.00040303 AU
897,647,519 km
Semi-major axis a 3.51554965 AU
525,918,744 km
Orbital period period 6.5900 years
2,407.6219 days
Date of perihelion transit Tp 2012-Feb-11 15:01:21
2,455,969.1259 JD
Next perihelion transit 2018-Sep-15 05:56
2,458,376.7478 JD
Argument of perihelion peri 172.58442490903°
Longitude of the ascending node node 195.39701448518°
Mean anomaly M 79.154730856238°
Mean motion n 0.14952514°/day
Closest approach to Earth* 2018-Sep-11
Distance of closest approach* 0.39085753 AU
58,471,455 km

* NOTE: values for the closest approach are computed for the time interval between 2013-Jan-01 and 2075-Dec-31, with a sampling interval of 1 day.