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Events of the Galilean Satellites for July 2008


Table of Events visible from New Zealand for July 2008.

Events of Jupiter's Galilean Satellites

Eclipses, occultations, transits and shadow transit of all four Galilean satellites will be occurring at regular intervals during July. A table of events visible during the month visible 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. Before opposition, before July 9 in 2008, they occur to the west of the planet, after that date to the east.

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 south pole of Jupiter is tilted slightly towards the Sun so that eclipses and occultations appear to take place to the south of Jupiter's equator. Transits and shadow events appear to take place a little north of Jupiter's 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 July 2008

The table shows the times (in UT) of events visible from New Zealand for July. To convert from UT to NZST: if the time is less that 12 hours, add 12 to the hours, or just treat the times as being pm. Thus July 5 at 09:40 UT is 21.40 (9.40 pm) NZST. If the time is 12 hours or more the event occurs after midnight, so add one to the date and subtract 12 from the hours to give NZST am. Thus July 2 at 17:58 UT, is July 3 5:58 am NZST.

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
July 2 17:58, 1 ShI 18:08, 1 TrI    
July 3 15:11, 1 EcD 16:51, 2 ShI 17:08, 2 TrI 17:36, 1 OcR
July 4 12:27, 1 ShI 12:34, 1 TrI 14:44, 1 ShE 14:51, 1 TrE
July 5 09:40, 1 EcD 11:38, 2 EcD 12:02, 1 OcR 14:36, 2 OcR
July 6 06:56, 1 ShI 07:00, 1 TrI 09:13, 1 ShE 09:17, 1 TrE
July 7 06:08, 2 ShI 06:14, 2 TrI 06:28, 1 OcR 08:52, 2 ShE
    July 7 cont. 08:58, 2 TrE 10:39, 3 ShI 10:50, 3 TrI 13:53, 3 ShE
    July 7 cont. 14:04, 3 TrE      
July 9 Jupiter at opposition
July 10 17:03, 1 OcD 19:21, 2 TrI 19:21, 1 EcR 19:26, 2 ShI
July 11 06:38, 4 OcD 10:46, 4 EcR 14:18, 1 TrI 14:22, 1 ShI
    July 11 cont. 16:35, 1 TrE 16:38, 1 ShE    
July 12 11:29, 1 OcD 13:50, 1 EcR 14:05, 2 OcD 17:02, 2 EcR
July 13 08:44, 1 TrI 08:50, 1 ShI 11:01, 1 TrE 11:08, 1 ShE
July 14 05:55, 1 OcD 08:19, 1 EcR 08:28, 2 TrI 08:43, 2 ShI
    July 14 cont. 11:12, 2 TrE 11:27, 2 ShE 14:07, 3 TrI 14:39, 3 ShI
    July 14 cont. 17:22, 3 TrE 17:54, 3 ShE    
July 16 06:21, 2 EcR      
July 17 18:47, 1 OcD      
July 18 07:54, 3 EcR 16:02, 1 TrI 16:17, 1 ShI 18:19, 1 TrE
    July 18 cont. 18:34, 1 ShE      
July 19 12:00, 4 TrI 13:13, 1 OcD 14:24, 4 ShI 15:38, 4 TrE
    July 19 cont. 15:44, 1 EcR 16:21, 2 OcD 18:05, 4 ShE  
July 20 10:29, 1 TrI 10:45, 1 ShI 12:46, 1 TrE 13:02, 1 ShE
July 21 07:39, 1 OcD 10:13, 1 EcR 10:42, 2 TrI 11:17, 2 ShI
    July 21 cont. 13:26, 2 TrE 14:02, 2 ShE 17:24, 3 TrI 18:39, 3 ShI
July 22 07:12, 1 TrE 07:31, 1 ShE    
July 23 08:59, 2 EcR      
July 25 07:03, 3 OcD 11:54, 3 EcR 17:47, 1 TrI 18:11, 1 ShI
July 26 14:57, 1 OcD 17:39, 1 EcR 18:37, 2 OcD  
July 27 12:14, 1 TrI 12:40, 1 ShI 14:30, 1 TrE 14:57, 1 ShE
July 28 09:23, 1 OcD 12:07, 1 EcR 12:56, 2 TrI 12:52, 2 ShI
    July 28 cont. 15:40, 2 TrE 16:36, 2 ShE    
July 29 06:40, 1 TrI 07:09, 1 ShI 08:57, 1 TrE 09:26, 1 ShE
July 30 06:36, 1 EcR 07:46, 2 OcD 11:36, 2 EcR  

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