From Terry...

Hi all,

1. Bright star to be occulted by asteroid, 20/21 July. The track crosses
Ireland diagonally from NW to SE, entering at Counties Mayo & Sligo, and exiting
at Wicklow, Wexford & E Waterford. It occurs at about 01.19 UT - that's 02.19
BST!
It will be a very interesting observation if you see it, and if you time
it accurately (to the nearest second, or better - preferably to 0.2 or even
0.1sec) you can do some real useful science!
The star is magnitude 6m.4, and will be occulted by 773 Irmintraud,
magnitude 13.8, so the drop in combined brightness will be 7.4 magnitudes - in
effect the star will totally disappear for up to 10 seconds or so! You''ll need to
be set up about 20 mts before the event, with the star (HIP 186, RA 0h 2m
24.167 secs, Dec +8 deg 57m 24.55 sec) clearly identified, your tracking on, your
timing ready, stopwatch or camera timer checked against an accurate time
source, etc. Time both disappearance & reappearance as accurately as possible. It's
worth looking for up to 15 mts before & after the nominal time, in case there
is a secondary occultation by a satellite of Irmintraud!
The following details were sent to me by Tolis Christo at Armagh
Observatory, who will co-ordinate any observations <aac.@arm.ac.uk>

"Hi Terry, I don't know whether you've made any plans for the Irmintraud
occultation on the night of the 20th July.
We here intend to undertake a little expedition and travel to the centre
of the track; the exact location is to be decided by the weather at the last
minute. For a 6th mag star, I think it is worth it.
I was wondering whether you know of any amateurs that might be willing to
observe from within the nominal track. Check the track map at
www.asteroidoccultation.com/2004_07/0721_773_1842_MapE.gif
If we get enough chords, we should be able to do a shape determination
(best-fit ellipsoid) with Irish-only data.
Thanks, Tolis."
CCD or Digital video camera observations are best, but even visual timings
with an accurate stopwatch will be useful if they are done properly.

2. There are still tickets for the two public lectures at the RDS Concert
Hall in Dublin 4, by two of the best-known names in modern physics/cosmology!

(1). On Monday July 19 Prof Kip Thorne will give a lecture entitled "Probing
the Universe and Black Holes with Gravitational Waves"

(2). On Friday July 23 Prof Sir Roger Penrose will talk on "Fashion, Faith &
Fantasy in Modern Physical Theories".

Both lectures start at 20.00, and are part of the 17th International Congress
on General Relativity & Gravitation, being held at the RDS. Tickets cost ???
20, (???10 students), and can be booked online at <www.gr17.com>

3. The ISS continues to make a nice series of evening passes for the next
week or so: details at <www.heavens-above.com>

4. The Sun has re-awakened, with some spectacular spots coming towards the
centre of the disc. Look out for possible aurorae over the next week or so.

5. Venus is now at maximum brightness as a morning star in the dawn twilight
- a beautiful sight for early risers!

6. Remember the next IAA "Solar Day" at Carnfunnock Country Park, near Larne,
on 31 July. More details later.

Clear Skies,

Terry Moseley

Hi all,

Our amazing run of weather for our IAA planned events at Carnunnock continued on Saturday with an almost cloudless sky for our latest 'Solar Day'. For 'our' events (as opposed to eclipses etc), that's a 100% record there, and about 17 out of 18 altogether, at all venues, since I started counting!
And the Sun obliged with a good-sized single spot, and a nice smaller pair, plus several prominences visible in the Coronadoes etc. We had a good steady stream of visitors, and all seemed interested & impressed.
Thanks to all who volunteered: we had a great selection of telescopes, ranging up to Danny Collins' 6" (150mm) refractor, and David Collins' (no relation) amazing 25 x 125 binocs! Andy set up his laptop to show the view from his latest H-Alpha instrument - very impressive. See photos on the IAA website: www.btinternet.com/~jimmyaquarius

Whirlpool Star Party: Ireland's premier astronomy event is only about 6 weeks away, from 17-19 September, in Birr, Co Offaly. Details of the programme are on: www.geocities.com/shannonsideac/
But, with due respect, the accommodation list for Birr on that site is rather meagre in scope & information! I have compiled a much bigger & more comprehensive list, and including latest prices, website & email addresses where known, locations, no of rooms, E/S or not, etc. .....
B&B accommodation in the immediate area is getting booked out, so better hurry up! The attached list gives details of all known accom in Birr & the surrounding area, in zones of increasing distance from Birr, up to about 20 miles away. It's as up to date as I can make it now, but better check all details of prices etc when you make your booking. I have attached it as a RTF file to beat the bug-gers!

Clear Skies,

Terry Moseley

Hi all,

Maximum of the Perseids meteor shower approaches, and conditions this year are very favourable, with no moonlight to worry about.

Some are already being seen each clear night, but the best is yet to come. They will increase in number each night for the next couple of days, reaching a maximum late on the night of 11/12 August, when up to 100 meteors per hour may be visible under good conditions!

There's already quite a lot of media interest: - I've already been interviewed on Radio Ulster, Evening Extra, & Belfast City Beat, and I'll be on Downtown 'Margie's Magazine' on Sunday (2-3 p.m.), and on Cool FM (Johny Hero) on Monday morning about 10.40. So this could be a good chance to promote astronomy & the IAA etc if the public ask you about the Perseids.

This shower occurs when the Earth passes through the trail of particles given off by Comet Swift-Tuttle, named after its discoverers.

A meteor is just the fiery death of one of these particles, which we see as it burns away during its high speed impact with our upper atmosphere. Most are just the size of a sand grain, brighter ones can be as big as a grape seed or apple pip, and a really bright one would be only the size of a pea! So we don't see the particle itself, just the fiery trail as it burns away at a collision speed of about 60 miles per second!

The Perseids are always one of the best annual showers, and with conditions this year being particularly favourable, let's hope for clear skies. Some experts also think that activity will be unusually high this year, and we may also get an extra early burst of activity just as darkness falls on Wed 11th. This is expected as we may pass through a dense 'filament' of particles given off by the comet at its penultimate perihelion passage in 1862. This is predicted for 21.50 BST, so we might just get the end of it as the sky darkens.

Activity should be quite high on the nights of 10/11, 11/12, and 12/13 August, with best rates in the early hours of 12 August, and the possible early burst of activity early on the previous evening. Perseids can appear in any part of the sky, but if you trace their paths back they will appear to come from Northern Perseus, which will be rising in the North East in the early evenings, getting high up in the Southern part of the sky just before dawn. The radiant moves slowly across the sky during August, and on the night of maximum it lies not far from the 'Double Cluster' in Perseus, or about 5 degrees N of Alpha Persei.

You'll see most meteors by looking at an altitude of about 50 degrees, and about 45 degrees to either side of the radiant, on whichever side the sky appears darker. But to get a proper view you must get away from all light pollution. If there's a lot of artificial light nearby, you might see only about one tenth as many meteors as if you were out in a dark rural sky.

So, if it's clear next Wednesday night, or even the nights before and after, have a look at the sky for as long as you can, and see some of these tiny visitors from space end their lives in such a spectacular fashion!

Clear Skies,

Terry Moseley

Hi all,

1. Just a year and a day after Neil Armstrong's visit, the SECOND man on the moon will be making a similar visit, to the same venue! Thanks to our own Ulsternaut (soon to be 'astronaut') Derek Heatly, for the following details:

On Thurs. Nov. 18 Gay Byrne will interview Buzz at 8pm in the National Concert Hall. Tickets are €35,50,70 - dinner with him afterwards is €350! Try booking on www.nch.ie or ring 01-417-0000 (003531 417 0000 from N.I.) The Armstrong event was superb, a unique occasion; so I'm sure Buzz will be worth hearing too.

2. Science Week at Maynooth.
Come to Maynooth and see the stars, learn more about IT etc. All these and more are on the programme for Science Week at Maynooth from 7th to 14th November. Everyone will get a welcome, and all the events are free.
Among the activities will be nightly viewing of the stars, which will begin at 8 pm if viewing conditions are right there. Career minded visitors will be able to hear what science graduates have to say about jobs in Irish industry. Anyone who wants to get hands-on experience of science should come along on Friday 12th for a series of demonstrations in biology, physics and computer science. To get the latest on what’s planned visit the website www.may.ie

3. Science photo competition.
From August to December, Irish Universities Promoting Science is running an exciting web photo competition for students under the theme, “Science is Fun”. Primary and post-primary school students can submit their photos either electronically from the website < www.universityscience.ie > or by post.
Each month, visitors to the website will be asked to vote for their favourite photo, as all pictures will be uploaded onto the site. A grand final of photos will be held in December, again picking the winners by popular vote. The winners will be presented with their prizes at the Young Scientist Exhibition in the RDS, Dublin in January
2005.
A good astro-photo could well have a good chance here!

Clear Skies,

Terry Moseley

Hi all,

1. A final reminder that Prof Mark Bailey, Director of Armagh Observatory, will open the new lecture season of the Irish Astronomical Association when he gives the "Ronnie Ormonde Memorial Lecture" on Wednesday 22 September. This will be held in Lecture Theatre 5, Stranmillis College, Stranmillis Road, Belfast, at 7.30 p.m. The talk is entitled: "The Origin of Comets and the Oort Cloud". Admission is free, including light refreshments, and all will be welcome.

2. The lecture by Prof. Leon Lederman, Nobel Laureate, on Wednesday, 22 Sep, at 7.00pm, TCD, entitled "The Search for Simplicity in the Universe" is booked out, but a live webcast will be available over the web. See www.ria.ie/events/lederman.html

3. "THE SOLAR SYSTEM - ITS ORIGIN AND EARLY HISTORY"
Dr Ian Sanders of TCD's Geology Dept is presenting a series of 6 lectures on this topic every Tuesday at 8pm starting October 12 in the Museum Building, Trinity College Dublin. This series of six illustrated lectures will attempt to explain in non-technical language how the solar system began. The lectures will explore the evidence in meteorites and lunar samples for the creation of the sun and planets and for early events in their history. Apply to Ms M. Duncan, Dept. of Geology, Trinity College, Dublin 2. Phone 01 608 1074; e-mail earth@tcd.ie. Fee is 60 (students/unwaged/pensioners 30euro).

4. SKY AT NIGHT: The next programme will be broadcast on Sunday evening as usual, but BBC4 will be showing a 10min. extended version of the programme on Monday at 20.30 the day after the main programme.
This may be because the repeat on the following Saturday BBC2 is being phased out?
The extra 10 mins. will feature the monthly night sky and can feature pictures from amateur astronomers. The main programme will be presented by Sir Patrick and Chris Lintott. (Thanks to Peter Paice for this info.)

Clear Skies,

Terry Moseley

Hi all,

TV Programmes:

1. Sunday, 12 Dec.:
8.00pm on Channel 4: What we still don't know (2/3):
Sir Martin Rees on the emergence of life and its place in the Universe. See www.channel4.com/science/microsites/W/wh...dont_know/index.html

2. Monday, 13 Dec.:
7.00pm, BBC4 TV, The Planets: the fate of our solar system.

3. Wednesday, 15 Dec.:
7.00pm, BBC4 TV, Bill Bryson: A Short History of Nearly Everything.
9.00pm, BBC4 TV, Light Fantastic: From light bulb to atomic bomb (3/4). Repeated 12.20am. See: www.bbc.co.uk/bbcfour/documentaries/features/light.shtml
10 20pm BBC2 TV, The Planets: Brief Encounters - a 10-min account of the 10-billion-year life of the solar system.
10.50pm BBC4 TV, Mark Steel on Einstein. Repeated 2.20am.

4. Thursday, 16 Dec.:
7.00pm, BBC4 TV, Light Fantastic. Repeated 1.40am

GEMINIDS: Don't forget the Geminid meteors, maximum on Monday night/Tuesday morning. See previous emails.

IAA LECTURE, Wed, 7.30 p.m. Dr John Butler will give a talk entitled "The 2003 Restoration of Armagh Observatory" (If you haven't visited the Observatory recently, you should do so - quite a few changes, including one completely new dome, a unique 'Human Orrery', and major refurbishments! But first, come & hear this lecture, to get the full story.) It will be at 7.30 p.m., Lecture Room 5, Main Building, Stranmillis College, Belfast, with plenty of free parking. Free admission as usual and there will be some free seasonal refreshments as well!


LIDL SKYLUX REFRACTOR: The Skylux refractor is still available in various Lidl stores throughout Ireland - thanks to all who have emailed me giving details. If you can't find one locally, just ring around.
This further information from IAA treasurer John Hall may be of interest:
"Hello Terry, I might as well add my tuppenceworth re the 70mm Skylux, I know I should not have bought it since I have enough telescopes already, 2 Dobs and 2 Refractors. However I managed to convince my better half that the Skylux would be a nice high tech "ornament" to reside in the corner of the sitting room.???( joke )
Just how good is this instrument ? The general finish is very good, but I noticed a lot of "plastic," for instance, the rack teeth seem to be made of this material then given a metallic finish, but essential parts subject to wear are all metal.
As regular skywatchers will know, during the last few weeks we seem to have wall to wall cloud cover , so the opportunity to do a star test did not exist. Last night, however, the sky was clear for about two hours, so out came the Skylux. I inserted a Ronchi grating ( 200 lines per inch ) at prime focus with the telescope pointed at Sirius. The result showed an apparently turned down edge objective, as the Ronchi lines were sharply bent at the edge, and as you know this fault is an image destroyer.
Remembering my days when I was trying to assemble a 100mm refractor, I recalled just this fault when I had tightened the objective lens down too tight ( you must have some play), so I removed the dewcap from the Skylux and tried to unscrew the objective retaining ring, and noticed that it was quite tight. I unscrewed it about half a turn, replaced the dewcap and repeated the Ronchi test, and believe it or not, the Ronchi lines were nice and straight right to the edge.
Saturn was high up so I got my best Nagler (7mm) and zeroed in. I have to say I was a little disappointed. This eyepiece gave a power of 100, and I expected to see at least the Cassini division, but there was no sign of it and the image of Saturn was soft and featureless, with some false colour. As a comparison my home made 100mm F13 refractor displayed a nice crisp image, with Cassini sharply visible.
Turning to the stars, Polaris was "star tested" with the Nagler and showed a reasonably good result. Possibly the lack of detail on Saturn can be explained by some surface roughness on the objective.
Finally, I noticed a nearby streetlamp seemed to be causing reflections into the field, this was eliminated by painting the inside of the shiny plastic drawtube with blackboard paint, this will help contrast as well."

Thanks, John. I suppose for £50 it's still good value, and maybe you didn't get a particularly good one. And I promise that's the last mention of the Skylux until next year!

Clear Skies (esp for Monday night!!)

Terry Moseley