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Events of the Galilean Satellites for May 2010


Table of Events visible from New Zealand for May 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 May. 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 May 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 noticable for the outer two satellites. Transits and shadw 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 May 2010

The table shows the times, in UT, of events visible from New Zealand for May. To convert times to NZST: for times greater than 12 hours UT, (as in May), add 1 to the date and subtract 12 hours. Thus 16:55 UT on May 1, is 4:55 am NZST on May 2.

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
May 1 16:55, 3 OcR      
May 2 18:40, 1 ShI      
May 3 15:56, 1 EcD      
May 4 15:24, 1 ShE 16:21, 2 EcD 16:25, 1 TrE 17:08, 4 TrE
May 6 16:17, 2 TrE      
May 8 16:53, 3 EcR 17:59, 3 OcD    
May 10 17:50, 1 EcD      
May 11 15:02, 1 ShI 16:09, 1 TrI 17:17, 1 ShE 18:23, 1 TrE
May 11 cont. 18:56, 2 EcD      
May 12 15:44, 1 OcR 16:53, 4 EcR    
May 13 16:14, 2 TrI 16:45, 2 ShE 19:03, 2 TrE  
May 15 17:31, 3 EcD      
May 18 16:56, 1 ShI 18:07, 1 TrI    
May 19 15:47, 3 TrE 17:43, 1 OcR    
May 20 14:51, 1 TrE 16:31, 2 ShI 19:00, 2 TrI  
May 22 16:04, 2 OcR      
May 25 18:50, 1 ShI      
May 26 14:58, 3 ShE 16:07, 1 EcD 16:52, 3 TrI  
May 27 14:34, 1 TrI 15:33, 1 ShE 16:48, 1 TrE 19:08, 2 ShI
May 28 14:10, 1 OcR      
May 29 18:45, 2 OcR      

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