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From: TerryMoselaol.com
Date: Tue, 21 Jun 2005 20:29:02 EDT
Subject: Longer nights, ISS, Nice conjunction, Jupiter

Hi all,

1. Good news for all astronomers - the nights are getting longer again - at 
least for those of us in the N. Hemisphere! The effect doesn't really become 
noticeable until about mid-July, but every little helps! But the latest sunset 
of the year, in our latitudes, does not occur until 25 June. 
2. The ISS is now giving another series of night-time passes above Ireland, 
at first just in the early mornings (i.e. after midnight), but soon those will 
extend into the late evenings, at least by clock time (BST). Get details for 
your location from www.heavens-above.com.

3. A CLOSE CALL! One of the best planetary conjunctions for many years to 
come is getting under way. As from tonight, Saturn, Venus and Mercury will all 
lie within a circle only 5 degrees across low in the evening twilight. And they 
will gradually get closer, with Venus and Mercury in particular having a VERY 
close pass.
   Brilliant Venus currently lies in the middle, with brightish Mercury to 
its right, and fainter Saturn further away to its left, all three in a straight 
line. Mercury and Saturn then both close in on Venus, from opposite 
directions. You'll almost certainly need binoculars to see Saturn, and they'll help for 
Mercury too. 
   DO NOT observe with binocs or a telescope anywhere near the Sun in the 
sky! If you want to try to observe these planets before sunset, stand somewhere 
from where the Sun is hidden, e.g. by a building or tree.
   Here are some details, for June evenings in Ireland:
22nd: Mercury, Venus & Saturn now within 5 degrees of each other.
24th: All are closer, Saturn is starting to dip below the original straight 
25th: Venus and Mercury now very close, Saturn starting to pass below and 
left of Venus.
26th:  Mercury, Venus & Saturn inside a circle about 1.5 across, Saturn 
vertically below the other pair.
27th, 18 30:  Mercury & Venus closest, about 4' apart, and still only about 
6' apart later in the evening twilight; Saturn lies 2.25 degrees to the lower 
28th: Mercury now lies close to the left of Venus; much fainter Saturn is now 
3.25 degrees to the lower right of Venus, and probably very hard to see in 
the bright twilight.
   The Mercury-Venus conjunction is a very close one: even in the later 
twilight on the 27th, when they have passed their closest point, they will still be 
only about 1/5 of a moon diameter apart! Telescopes and cameras at the ready, 

4. Giant planet JUPITER gives a grand finale performance with a series of 
satellite events on 27/28 June. There are 4 events, with two sets of triple 
overlaps. How many can you see before Jupiter gets too low? For convenience, I'll 
give the times in BST:

22.00: Io transit starts.
22.18: Europa transit starts
23.15: Io shadow transit starts
00.11: Io transit ends
00.54: Europa shadow transit starts
01.01: Europa transit ends
01.25: Io shadow transit ends
03.23 Europa shadow transit ends.
   The latter will be too late for anywhere in Ireland, but observers in the 
far SW should just be able to catch all the others, and even in the North end 
of the island it will theoretically be possible to see at least part of all 
four events.

Send any observations of this, and of anything else, particularly photos of 
the ISS and the planetary conjunction, to Andy McCrea for STARDUST 
andrewmccreaa.freeserve.co.uk and to John Hall for the website 

Clear skies,

Terry Moseley


Last Revised: 2005 June 23rd
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