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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 Cassiopeia on August, 17 2018
High Precision Live Sky Chart
02h 53m 04s
+63° 54’ 06”
 = 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

Comet 21P/Giacobini-Zinner is circumpolar from Greenwich, United Kingdom [change] and transits at 05:10 UTC (altitude: 77.6°)

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 Right AscensionR.A. DeclinationDec. MagnitudeMag Constellation
2018 Aug 10 01h 31m 40s +66° 23’ 57” 12.72 Cassiopeia
2018 Aug 11 01h 42m 57s +66° 14’ 58” 12.67 Cassiopeia
2018 Aug 12 01h 54m 21s +66° 02’ 25” 12.63 Cassiopeia
2018 Aug 13 02h 05m 45s +65° 46’ 06” 12.58 Cassiopeia
2018 Aug 14 02h 17m 09s +65° 25’ 58” 12.54 Cassiopeia
2018 Aug 15 02h 28m 28s +65° 01’ 53” 12.50 Cassiopeia
2018 Aug 16 02h 39m 41s +64° 33’ 47” 12.46 Cassiopeia
2018 Aug 17 02h 50m 43s +64° 01’ 39” 12.41 Cassiopeia
2018 Aug 18 03h 01m 32s +63° 25’ 26” 12.37 Cassiopeia
2018 Aug 19 03h 12m 07s +62° 45’ 07” 12.33 Cassiopeia
2018 Aug 20 03h 22m 27s +62° 00’ 45” 12.29 Camelopardalis
2018 Aug 21 03h 32m 27s +61° 12’ 20” 12.25 Camelopardalis
2018 Aug 22 03h 42m 10s +60° 19’ 55” 12.22 Camelopardalis
2018 Aug 23 03h 51m 32s +59° 23’ 35” 12.18 Camelopardalis

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 29 December 2017 00:00 UTC (JD: 2458117.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.71048685
Orbit inclination i 32.00024171°
Perihelion distance q 1.01315110 AU
151,565,248 km
Aphelion distance Q 5.98584778 AU
895,470,083 km
Semi-major axis a 3.49949944 AU
523,517,666 km
Orbital period period 6.5500 years
2,391.1527 days
Date of perihelion transit Tp 2018-Sep-10 06:27:47
2,458,371.7693 JD
Argument of perihelion peri 172.83191932167°
Longitude of the ascending node node 195.40028173068°
Mean anomaly M 321.71848657008°
Mean motion n 0.15055500°/day
Closest approach to Earth* 2058-Sep-18
Distance of closest approach* 0.37340131 AU
55,860,041 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.