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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 Aquila on April, 23 2018
High Precision Live Sky Chart
19h 29m 26s
+15° 25’ 09”
 = 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: 74.6°
Max altitude: 53.9°
Azimuth: 285.4°

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
2018 Apr 16 16.17 19h 18m 52s +12° 54’ 08” Aquila
2018 Apr 17 16.12 19h 20m 23s +13° 14’ 56” Aquila
2018 Apr 18 16.07 19h 21m 53s +13° 35’ 58” Aquila
2018 Apr 19 16.02 19h 23m 25s +13° 57’ 18” Aquila
2018 Apr 20 15.97 19h 24m 56s +14° 18’ 51” Aquila
2018 Apr 21 15.92 19h 26m 26s +14° 40’ 41” Aquila
2018 Apr 22 15.87 19h 27m 56s +15° 02’ 48” Aquila
2018 Apr 23 15.82 19h 29m 26s +15° 25’ 09” Aquila
2018 Apr 24 15.77 19h 30m 57s +15° 47’ 45” Aquila
2018 Apr 25 15.71 19h 32m 27s +16° 10’ 38” Aquila
2018 Apr 26 15.66 19h 33m 59s +16° 33’ 47” Sagitta
2018 Apr 27 15.61 19h 35m 29s +16° 57’ 11” Sagitta
2018 Apr 28 15.56 19h 36m 59s +17° 20’ 52” Sagitta
2018 Apr 29 15.50 19h 38m 30s +17° 44’ 48” Sagitta

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 14 July 2008 00:00 UTC (JD: 2454662.5). Source: JPL Small-Body Database

Element Symbol Value
Orbit eccentricity e 0.70613929
Orbit inclination i 31.85199570°
Perihelion distance q 1.03524873 AU
154,871,006 km
Aphelion distance Q 6.01059779 AU
899,172,632 km
Semi-major axis a 3.52292326 AU
527,021,819 km
Orbital period period 6.6100 years
2,415.2006 days
Date of perihelion transit Tp 2005-Jul-02 22:58:55
2,453,554.4576 JD
Next perihelion transit 2012-Feb-12 03:47
2,455,969.6582 JD
Argument of perihelion peri 172.5126988044°
Longitude of the ascending node node 195.39380765818°
Mean anomaly M 165.16030751433°
Mean motion n 0.14905594°/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.