Thursday, 8 March 2012

Possible aurora tonight, + lots more.

Hi all, 
(Apologies for some repetition in this bulletin, but a number of new people have asked to be added to the list, so I want to inform them re all events, not just the aurora)
1. Possible Aurora Tonight.  
As you may be aware, the Sun unleashed a massive Coronal Mass Ejection towards Earth yesterday, an event which can cause aurorae here on Earth. I didn't send out an alert last night for 3 reasons:
1. Any expected aurora activity would not start until just about dawn this morning in Ireland.
2. The weather forecast for last night was very bad.
3. The Moon is Full, so all but a bright aurora would be drowned out in the Moonlight.
   So it seems that our North American cousins were much better placed to see any auroral activity, as it was still dark there after sunrise here. Reports are already coming in of a good aurora visible there. But there is a chance that auroral activity could continue into the period when darkness occurs again here in Ireland this evening.
   Unfortunately -
1. The weather forecast is still bad, and
2. There will still be a Full Moon.
   But if we do happen to get any clear sky, and if there is a bright aurora visible from here, then we would still see it in spite of the moonlight.
   As for any aurora, the best location is to go as far North as possible, or at least get to the North side of any brightly lit towns or cities. You'll also want to have a fairly clear North horizon, although if the aurora is a strong one, it can spread right up into the zenith, or overhead point in the sky. Look out for red or green or purple coloured bands or rays or patterns or even an overall bright orange glow. And if you are going out from a brightly lit room, or from exposure to bright vehicle lights etc, give yourself at least 5-10 minutes for your eyes to dark-adapt.
   It's just unfortunate that the best of this particular event may be happening during our daylight, and the weather forecast for tonight is not good, and the Moon is Full!
   But this event indicates that activity on the Sun is increasing, and we can expect more events like this over the coming years, hopefully with more auspicious circumstances for us.
   If you DO see anything, please let me know, by email or text, or post to the IAA website -
2. "The Sky at Night", March:  Sir Patrick Moore looks at 'citizen science' and how ordinary people can contribute to the world of science. As we heard in the fascinating IAA lecture by Dave McDonald last night, and in other lectures such as from the world's leading supernova discoverer Tom Boles, this is an area in which the amateur astronomer can play a very important part.

Transmissions: Thu 7:30pm BBC FOUR; Fri 12:15am BBC FOUR; Sat 12:00pm BBC 2 NI; Sun 12:55am BBC FOUR

3. IAA LECTURE, 21 March:  The Astronomical Association's next public lecture will be given by Derek Heatly: Title: "Stop the World, And Let Me Off".  The lecture is on WEDNESDAY 21 March, at 7.30 p.m., in the Bell Lecture Theatre, Physics Building, Queen's University, Belfast.
   Derek, who features prominently at almost all our public events, is going to be the first ever astronaut from N. Ireland, assuming all goes to plan. He has booked a flight into space with Richard Branson's 'Virgin Galactic', and has already been given his number in the launch sequence, among other celebrities and private individuals. He may get his flight next year, depending on how well the first commercial flights go.
   Derek has already been up to the edge of space in a high-powered supersonic Russian Mig jet fighter, and has done weightless flights in the Russian aircraft used to train their astronauts. He will tell us of the latest developments in the Virgin Galactic programme, and show videos of the test flights of the 'spaceplane' in which he is due to launch.
  It's great that one of our own members has taken the audacious step to fly into space, so this promises to be a fascinating evening. And before you ask, I don't know if there will be a toilet on board either!
ADMISSION IS FREE, as always, and includes light refreshments. Everyone is welcome! Full details of the rest of the programme are on the website:  
4. IAA at Lough Neagh Discovery Centre, near Lurgan, on 30 March, evening: This event had already been booked well before the BBC Stargazing Live event. It too will have our usual format (but without the broadcast this time). This will be similar to other recent events, except that we will be running the whole event ourselves, with the Stardome of course (loaned from Armagh Planetarium with thanks once again). More details next time. See   
5. COSMOS 2012: The Midlands Astronomy Club have finalised the programme for their very popular annual star party, at Annaharvey Farm, just outside Tullamore, Co Offaly, on the W/E of 13-15 April. Speakers include:
- Thierry Legault, world-renowned French astrophotographer
- Girvan McKay, Midlands Astronomy Club
- Eamon Ansbro, Kingsland Observatory, Roscommon
- Kevin Berwick, Dublin
- Dermot Gannon, Midlands Astronomy Club
- Apostolos Christou, Armagh Observatory
- Lawrence Rigney, Midlands Astronomy Club
More details are available on the website
6. Armagh Observatory Public Astronomy Event, 17 March.
AO's next public event will be a pair of back-to-back public lectures in St. Patrick's Trian on the morning of St. Patrick's Day, Saturday 17th March, followed by tours of the Observatory Grounds and Astropark, as its contribution to Armagh City and District's Saint Patrick's Day festivities on Saturday, 17th March 2012 

The programme of fascinating astronomical talks, "Discovering the Universe", begins with light refreshments at 10:30 am in St. Patrick's Trian, Armagh. Two public lectures are being provided, one on the risk to Earth posed by comet and asteroid impacts with our planet, the other a review of efforts during the eighteenth century to measure the size of our solar system and the role played by very rare planetary transits across the face of our Sun. The next Transit of Venus, the last for more than a hundred years, will be visible from Europe on 6th June this year.

   The free public lectures will take place in the Rotunda Theatre, St. Patrick's Trian, each lasting an hour and with time for questions, ending at 1:00 pm.
The first talk, beginning at 11:00, is by Mr Jay Tate, Director of the Spaceguard Centre, Knighton,
Wales. His presentation, "The Science of Armageddon: an Update", will explain how the Earth has a long
and violent history of collisions with extraterrestrial bodies such as asteroids and comets, and how some
of these impacts have been large enough to cause huge environmental upheavals, mass extinctions of life
and severe changes to global climate and geography. Massively more destructive than the most powerful
nuclear weapons, such impacts represent the most damaging natural hazard likely to end civilization as
we know it. The talk will review the nature and extent of the Near-Earth Object (NEO) impact hazard and
bring us up to date with the latest understanding in the field: how the risk can be dealt with and what is
currently being done.
   Jay Tate is one of the world's leading authorities in this subject, having led efforts over the past fifteen years to highlight the risk to civilization posed by these extreme events and improve public understanding of
natural events about which, fortunately, we have no direct experience.
The second talk, at 12:00, will be given by Armagh Astronomer Dr John Butler. He will provide a
contrasting historical talk, "Measuring the Solar System: The Eighteenth Century Transits of Venus".
The eighteenth century was a "Golden Age" for science, and many new and important discoveries were
made in astronomy. The two eighteenth-century Transits of Venus, in 1761 and 1769, provided a rare
opportunity to determine the fundamental unit of astronomical distance: the distance from the Earth to the
Sun. The talk will describe how astronomers across the world united in this, the first great international
scientific project. It will explain the difficulties they faced in carrying out their observations and their
eventual success and the scientific legacy of their efforts.
   John Butler has worked at Armagh for nearly all his astronomical career. He was instrumental in the design and construction of the Astropark, and has led efforts during the past twenty years to conserve and preserve the built heritage of the Armagh Observatory and to calibrate the unique meteorological record, the longest daily climate series in the UK and Ireland. His research interests encompass cool stars, the effects of solar variability on climate, and the history of astronomy, and he is well known for his active involvement in the community of Armagh and for discovering an exceptional flare on the star HD 6090, called "Butler's star".

   Everyone is welcome to these events. Free tickets for the "Discovering the Universe" presentations are available from Mrs Aileen McKee, Armagh Observatory, College Hill, Armagh; Tel. 028-3752-2928; E-mail: No booking is necessary to join the guided tour "Bringing Heaven Down to Earth" or the Observatory tour and exhibition. Meet outside the Observatory at 2.30 pm and 4.00 pm respectively.

    FOR FURTHER INFORMATION PLEASE CONTACT: John McFarland at the Armagh Observatory, College Hill, Armagh, BT61 9DG. Tel. 028-3752-2928; FAX: 028-3752-7174

7. Lectures in RDS, Dublin: In celebration of Dublin's status as European City of Science 2012, UCD School of Physics has teamed up with the RDS to bring some of the world's leading physicists to speak in Dublin about the latest developments in their fields of research. Please note these lectures are aimed at a public audience. Full details of these lectures and booking information can be found on the UCD website:

Titan - The Moon that thinks it's a Planet - Prof. John Zarnecki. Tuesday March 20, 2012

Minerva Suite; 6.00pm – 7.30pm.

Lasers in the Fast Lane - Prof. Wilson Sibbett. Tuesday May 15, 2012. RDS Concert Hall

6.00pm - 7.30pm

8. Venus closes on Jupiter, Mercury still visible: Venus is now exceptionally prominent in the evening twilight as the brilliant 'evening star'. It is now much closer to Jupiter, which is noticeably fainter than Venus, but still much brighter than any of the stars. On this (8th) and following evenings the separation will be: 5 deg 23'; 9th = 4 deg 42'; 10th = 4 deg 1'; 11th = 3 deg 30'; 12th 3 deg 8'; 13th 2 deg 59', 14th 3 deg 5'.
   And you can use these two planets as finders for the most elusive of the other naked-eye planets: Mercury, the innermost planet. It can be quite bright, as at present, but is always close to the Sun in the sky, so we can only see it low down in fairly bright twilight. At the moment it's still well placed for viewing from Ireland, but is getting fainter and closer to the Sun, so after the weekend it will be quite hard to see.
   At about 30 minutes after local sunset, follow the line from Jupiter and Venus down towards the horizon at an angle of about 45 degrees, and then look a bit to the left of that line, and about 5 - 10 degrees above the horizon. 5 degrees is about the width of your clenched fist, across the knuckles, when held out at arm's length in front of you. Mercury will look like a twinkling star glimmering through the twilight. It's still almost as bright as the brightest stars, but is quite hard to see because of the bright sky background. If you don't see it at first, keep looking up until about 50 minutes after sunset, a bit closer to the horizon after every 5 minutes or so, after which time it will be too low to be visible.
  Use binoculars if you have them, but DO NOT look while the Sun is above the horizon in case you accidentally get it in the field of view and blind yourself!
9. Record Close Moon 'could have sunk' the Titanic.
An article in 'Sky & Telescope' explores the idea that the moon's closest approach to Earth for 1,400 years, combined with Earth's perihelion and a spring tide, may have indirectly contributed to the disaster, which occurred on 14 April 1912. All these factors contributed to abnormally high sea levels which may have helped dislodge grounded icebergs and sent them into the shipping lanes of the North Atlantic. "Of course, the ultimate cause of the accident was that the ship struck an iceberg," said lead researcher Dr Donald Olson at Texas State University.
    Titanic's fate might have been sealed four months earlier on 4 January when there was a very close Full Moon and resulting spring tide. During a spring tide the Sun and Moon line up and the combined effect of their gravity causes sea level to rise exceptionally high. On 4 January, 1912, the tug of gravity was stronger than usual. The Moon's perigee - its closest approach to the Earth - was closer than it had been for 1,400 years and came within six minutes of the full Moon. In addition, the Earth's perihelion, the point at which its orbit brings it closest to the Sun, had occurred just the day before. 
   "It was the closest approach of the Moon to the Earth in more than 1,400 years and this configuration maximised the Moon's tide-raising forces on Earth's oceans," said Dr Olson. "That's remarkable. The full Moon could be any time of the month. The perigee could be any time of the month." The scientists explain how a freak high tide would have dislodged many of the stranded icebergs and released them into the southbound ocean currents. They would have had just enough time to congregate in the shipping lanes for their fateful encounter with the Titanic.
   Dr Olson explained: "As icebergs travel south, they often drift into shallow water and pause along the coasts of Labrador and Newfoundland. But an extremely high spring tide could refloat them, and the ebb tide would carry them back out into the Labrador Current where the icebergs would resume drifting southward. "That could explain the abundant icebergs in the spring of 1912. We don't claim to know exactly where the Titanic iceberg was in January 1912 - nobody can know that - but this is a plausible scenario intended to be scientifically reasonable."
10. ANOTHER ASTEROID CLOSE MISS: A 150-foot asteroid called 2012 DA14 will pass so close to Earth next year it will fly UNDER man-made satellites orbiting our planet. This body is a good bit bigger than other recent near-miss objects! Nasa's Impact Risk report said that the odds of the space rock actually hitting Earth are very low indeed - but on 2013 February 15 it will pass just 17,000 miles from Earth, just a bit more than twice the Earth's diameter!
   If an asteroid of that size hit our our planet, it would cause an explosion similar to a major nuclear blast. Astronomers from the Observatory Astronómico de La Sagra in Spain spotted 2012 DA14 in late February and its orbit has been calculated to be very similar to Earth's. 
   17,000 miles is much closer than many of our own orbiting satellites. This is believed to be the closest pass of a reasonable-sized asteroid ever seen before the actual pass itself.
   In astronomical terms, 17,000 miles is pretty close, but in practical terms it's a clear miss.  After next year, 2012 DA14's closest brush with Earth will come in 2020, but even then the odds of an impact will be less than the chance of being hit by lightning in your lifetime – 1 in 100,000.
   I'll update you closer to the time on how to observe this asteroid during its flyby
11: Earth Hour 2012 March 31, 20:30 - 21:30. Switch off all unnecessary lights, see the sky, and save the planet! Take part in a global call to action to highlight concerns about climate change and the way we are wasting the worlds limited resources
12. TWITTER: the IAA now has a twitter account. twitter@IaaAstro
13. BBC THINGS TO DO WEBSITE: See the forthcoming IAA events on  
14. JOINING the IRISH ASTRONOMICAL ASSOCIATION is now even easier: This link downloads a Word document to join the IAA.  See also
Clear skies,
Terry Moseley

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