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Events of the Galilean Satellites for June 2010


Table of Events visible from New Zealand for June 2010.

Events of Jupiter's Galilean Satellites

Eclipses, occultations, transits and shadow transit of all four Galilean satellites will be occurring at regular intervals during June. A table of events visible during the month from NZ is included.

Eclipses occur when a satellite moves through the shadow of Jupiter. As it moves into the shadow the satellite will gradually fade from view and disappear. When it comes out of the shadow a faint spot of light will appear and gradually brighten.
Occultations occur when a satellite moves behind Jupiter as seen from the Earth. Hence during an occultation the satellite is hidden by the planet.
Transits occur when a satellite moves across the face of Jupiter as seen from the Earth.
Shadow transits occur when the shadow of the satellite cast by the Sun moves across the face of the planet

Occultations always start at the western limb of Jupiter and end at the east. Transits always start at the eastern limb of the planet and end at the west. In both cases the satellite will appear to "sink" into the bright limb of Jupiter at the ingress and gradually emerge from the limb of Jupiter at an egress.

In general eclipse events take place when the satellite is a small distance away from Jupiter as seen from the Earth. After conjunction, as in June 2010, they occur to the west of the planet.

All these events can be observed through a small telescope. Note that when Jupiter is viewed through an undriven telescope its image will drift to the west. This enables the west side of the planet to be determined.

In the case of disappearances into eclipse (EcD) the satellite is likely to be visible as it fades for a minute or two after the predicted time. For reappearances (EcR) the satellite will start to emerge a minute or two before the predicted time.

At present the north pole of Jupiter is tilted slightly towards the Sun. As a result of the slight tilt eclipses and occultations appear to take place to the north of the planets equator, especially noticeable for the outer two satellites. Transits and shadow transits will cross the planet south of the equator. From New Zealand Jupiter's north pole is the lower pole of the planet.

Table of Galilean Satellite events visible from New Zealand for June 2010

The table shows the times, in UT, of events visible from New Zealand for June. To convert times to NZST: for times greater than 12 hours UT, (as in June), add 1 to the date and subtract 12 hours. Thus 15:40 UT on June 2, is 3:40 am NZST on June 3.

Times of events are adapted from those given by Dave Herald's OCCULT 4 program.

Explanation:
Satellites: 1 = Io, 2 = Europa, 3 = Ganymede, 4 = Callisto.
EcD = Eclipse disappearance, EcR = Eclipse reappearance
OcD = Occultation disappearance, OcR = Occultation reappearance
TrI = Transit Ingress (start), TrE = Transit Egress (end)
ShI = Shadow transit start, ShE = Shadow Transit end.

Date Time UT,  Event Time UT,  Event Time UT,  Event Time UT,  Event
June 2 15:40, 3 ShI 18:01, 1 EcD 18:53, 3 ShE  
June 3 15:12, 1 ShI 16:31, 1 TrI 17:27, 1 ShE 18:45, 1 TrE
June 4 16:07, 1 OcR      
June 5 15:57, 2 EcD      
June 6 14:13, 3 OcR 16:36, 4 ShI    
June 7 13:48, 2 TrI 13:53, 2 ShE 16:34, 2 TrE  
June 10 17:06, 1 ShI 18:27, 1 TrI 19:20, 1 ShE  
June 11 14:24, 1 EcD 18:03, 1 OcR    
June 12 13:49, 1 ShE 15:09, 1 TrE 18:32, 2 EcD  
June 13 15:04, 3 OcD 18:19, 3 OcR    
June 14 13:41, 2 ShI 16:28, 2 TrI 16:29, 2 ShE 19:13, 2 TrE
June 15 15:53, 4 OcD 16:59, 4 OcR    
June 16 13:23, 2 OcR      
June 17 19:00, 1 ShI      
June 18 16:18, 1 EcD      
June 19 13:28, 1 ShI 14:50, 1 TrI 15:43, 1 ShE 17:04, 1 TrE
June 20 13:34, 3 EcD 14:26, 1 OcR 16:52, 3 EcR 19:19, 3 OcD
June 21 16:17, 2 ShI 19:06, 2 ShE 19:06, 2 TrI  
June 23 13:43, 4 ShE 15:59, 2 OcR    
June 25 18:12, 1 EcD      
June 26 15:22, 1 ShI 16:44, 1 TrI 17:36, 1 ShE 18:58, 1 TrE
June 27 12:41, 1 EcD 16:20, 1 OcR 17:35, 3 EcD  
June 28 13:26, 1 TrE 18:53, 2 ShI    
June 30 13:00, 2 EcD 18:34, 2 OcR    

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