1. COSMOS 2017: 31 March to 02 April. Shamrock Lodge Hotel, Athlone. Programme
details are at http://www.cosmosstarparty.ie/
NB. If anyone wants a lift from the greater Belfast / Lagan Valley area, Danny Collins will be leaving from the Lisburn area on Friday morning.
Also, if anyone needs accommodation he has a twin room in the Shamrock Lodge Hotel, and as someone else has had to cancel, there is a bed available for anyone who is happy to share. If you are interested, contact Danny directly right away on +44(0)7799533731 or firstname.lastname@example.org
2. NEWS ITEM update after yesterday's lecture. I just had to include this!
Explaining the accelerating expansion of the universe without dark energy. Royal Astronomical Society press release: 30 March 2017
Enigmatic dark energy, thought to make up 68% of the universe, may not exist at all, according to a Hungarian-American team. The researchers believe that standard models of the universe fail to take account of its changing structure, but that once this is done the need for dark energy disappears. The team publish their results in a paper in Monthly Notices of the Royal Astronomical Society.
Our universe was formed in the Big Bang, 13.8 billion years ago, and has been expanding ever since. The key piece of evidence for this expansion is Hubble's law, based on observations of galaxies, which states that on average, the speed with which a galaxy moves away from us is proportional to its distance.
Astronomers measure this velocity of recession by looking at lines in the spectrum of a galaxy, which shift more towards red the faster the galaxy is moving away. From the 1920s, mapping the velocities of galaxies led scientists to conclude that the whole universe is expanding, and that it began life as a vanishingly small point.
In the second half of the twentieth century, astronomers found evidence for unseen 'dark' matter by observing that something extra was needed to explain the motion of stars within galaxies. Dark matter is now thought to make up 27% of the content of universe (in contrast 'ordinary' matter amounts to only 5%).
Observations of the explosions of white dwarf stars in binary systems, so-called Type Ia supernovae, in the 1990s then led scientists to the conclusion that a third component, dark energy, made up 68% of the cosmos, and is responsible for driving an acceleration in the expansion of the universe.
In the new work, the researchers, led by PhD student Gábor Rácz of Eötvös Loránd University in Hungary, question the existence of dark energy and suggest an alternative explanation. They argue that conventional models of cosmology (the study of the origin and evolution of the universe), rely on approximations that ignore its structure, and where matter is assumed to have a uniform density.
"Einstein's equations of general relativity that describe the expansion of the universe are so complex mathematically that for a hundred years no solutions accounting for the effect of cosmic structures have been found. We know from very precise supernova observations that the universe is accelerating, but at the same time we rely on coarse approximations to Einstein's equations which may introduce serious side-effects, such as the need for dark energy, in the models designed to fit the observational data." explains Dr László Dobos, co-author of the paper, also at Eötvös Loránd University.
In practice, normal and dark matter appear to fill the universe with a foam-like structure, where galaxies are located on the thin walls between bubbles, and are grouped into superclusters. The insides of the bubbles are in contrast almost empty of both kinds of matter.
Using a computer simulation to model the effect of gravity on the distribution of millions of particles of dark matter, the scientists reconstructed the evolution of the universe, including the early clumping of matter, and the formation of large scale structure. Unlike conventional simulations with a smoothly expanding universe, taking the structure into account led to a model where different regions of the cosmos expand at different rate. The average expansion rate though is consistent with present observations, which suggest an overall acceleration.
Dr Dobos adds: "The theory of general relativity is fundamental in understanding the way the universe evolves. We do not question its validity; we question the validity of the approximate solutions. Our findings rely on a mathematical conjecture which permits the differential expansion of space, consistent with general relativity, and they show how the formation of complex structures of matter affects the expansion. These issues were previously swept under the rug but taking them into account can explain the acceleration without the need for dark energy."
If this finding is upheld, it could have a significant impact on models of the universe and the direction of research in physics. For the past 20 years, astronomers and theoretical physicists have speculated on the nature of dark energy, but it remains an unsolved mystery. With the new model, the team expect at the very least to start a lively debate.
3. Mercury well presented in evening sky. The innermost planet in our SS continues it's favourable elongation in the W sky for another week or so. (Sorry, I accidentally edited out this item from previous bulletin.) Look low in the W to NW from about 30 minutes after sunset.It's still quite bright, but will be fading noticeably during the first week in April, so look as soon as you get a clear sky. www.heavens-above.com will give details for your own location.
4. IAA AGM + Telescope Auction + Bring & Buy + Fix my 'scope! 12 April
The IAA AGM will be held in the usual venue at QUB at 7.30 p.m. Details are in an insert with the latest Stardust, which you should have got. After the official business we will be having -
* An auction of surplus IAA telescopes, of all sizes up to a 200mm equatorial reflector. Also lots of ancillary equipment. No reasonable offer will be refused, so this is your chance to pick up a real bargain.
* A bring and buy sale - bring along any of your own surplus gear, DVD's, books & magazines etc, and sell at whatever price you'll accept. For buyers, there are usually some good bargains here too.
So bring plenty of cash and change in notes, £1, £2, 50p's etc.
* If you already have a telescope, but are not sure how to use it, or you think something may be wrong with it, bring it along (if it's portable) and ask our experts for help.
FREE REFRESHMENTS in the form of the usual biccies, tea and coffee. All welcome!
TIME: 7.30 p.m., Bell Lecture Theatre, Physics Building, QUB.
Free admission. Free parking on QUB campus after 5.30 p.m. http://irishastro.org.uk/
5. IAA Observing nights, Delamont Country Park, Killyleagh Co Down:
6. RGO Astrophotography contest.
With a week left until submissions close for the Insight Astronomy Photographer of the Year contest, the Royal Observatory Greenwich has released images of some of the entries.
7. Heavens Above: AstroPhoto Exhibition in Downpatrick.
The superb exhibition of locally taken astro-photographs, which had very successful runs in the Linenhall Library In Belfast, and Clotworthy Arts Centre in Antrim, and the Island Arts Centre in Lisburn has transferred to the St Patrick's centre, Downpatrick, and runs there until 31 March.
After that, it will open in Bangor in July.
There are also 5 movies, covering solar eclipse, auroras and conjunctions, playing on a loop all day and now also viewing in the Centre reception.
Thanks again to Bernie Brown for setting this up.
8. ISS. The ISS commenced a series of evening passes over Ireland on 28 March, just in time for COSMOS. Details as always on the excellent free site www.heavens-above.com. This site also has general information on most things visible in the night sky, including comets, and now solar eclipses.
9. BBC Stargazing Live, from Australia. 8 p.m., 28 - 30 March. Presented by B COX, presumably because his name is the same upside down!
10. Light Pollution Campaign Survey: Sinead Allen, a student in at the Crawford College of Art and Design in Cork and a member of the Cork Astronomy Club, is developing an exhibition to educate the public on the issue of light pollution as part of her college project. She is collecting relevant data, regarding historical, environmental and societal impact. The aim is to include contributions from individuals and groups with particular interest in the topic. It would be greatly appreciated if the short survey accessible at the following link could be filled out by recipients of this bulletin.. https://goo.gl/forms/
11. AstroCamp 2017 The European Southern Observatory (ESO) and the Centre for Astrophysics of the University of Porto (CAUP) are collaborating to support AstroCamp 2017, an astronomy-focused summer academic programme for secondary school students. The Summer AstroCamp 2017 will be held from 6 to 20 August in northern Portugal, at the Centre for Environmental Education and Interpretation of the Corno de Bico Protected Landscape. The applicant with the best application from one of ESO's Member States who is eligible to apply will win a bursary offered by ESO that will cover the camp fee.
Read more http://www.eso.org/public/
12. Backyard Worlds: Planet Nine. Backyard Worlds is hoping to discover a large planet at the fringes of our solar system — a world astronomers call Planet Nine. But Backyard Worlds need your help! Finding such dim objects requires combing through images by eye, to distinguish moving celestial bodies from ghosts and other artifacts. So come and join the search — there are many images to look through. In the end you might discover a rogue world that's even nearer to the Sun than Proxima Centauri! Discover more about the project and how to contribute here: https://www.zooniverse.org/
13. Blackrock Castle Observatory Space Camps, July 10 - 21
Book your space camper in for a fun filled week of space and science activities.
Join us each day from 9:30 to 12:30.
Week 1 | July 10 - 14 | suitable for ages 7 to 9
Week 2 | July 17 - 21 | suitable for ages 10 to 12
The cost for each Space Camper is €95 per child which includes 1 week of Space Camp, Space Camp t-shirt & all activity materials.
Payment must be paid before your chosen Space Camp begins. 10% Discounts apply for members and siblings attending.
14. Heavens Above has new solar eclipse feature:
Heavens-above.com has a new feature on solar eclipses, from 1900 to 2100. They are grouped in thumbnail maps covering 3 year periods, thus the opening page lists those from 2017 to 2020. You can select other dates from the arrows beside the year date.
15. Total Solar Eclipse, USA, 21 August: Lots of people are asking about seeing this eclipse - the most accessible one for many years to come. See http://eclipsewise.com/solar/
For information about the eclipse see also 365 Days Of Astronomy: It's time for Totality 2017 | 365 Days of Astronomy and https://www.sciencedaily.com/
The weather prospects are much better on the West side of the Mississippi - see: http://eclipsophile.com/wp-
16: FUTURE EVENTS ALERT:
* Global Astronomy Month: April 2017. More information: http://www.
* Earth Day / March for Science, April 22: In view of the latest attacks on science, this would be an opportunity to stand up and show support for science and scientists. It is hoped that something will be organised locally, in both Belfast and Dublin. More later. https://www.facebook.com/
* Solar Day, Dunsink Observatory: 17 June.
* Starmus Festival IV: Life And The Universe: 18–23 June 2017. Location: Trondheim, Norway. More information: https://www.starmus.com/
* IAA Midsummer BBQ event. 24 June.
* European Week of Astronomy and Space Science (EWASS): 26–30 June 201,: Prague, Czech Republic. More information: http://eas.unige.ch/EWASS2017/
* Asteroid Day: 30 June 2017. Location: Around the world. More Information: http://asteroidday.org/
* ISSP: Major Event: The International Space Studies Programme (ISSP) will be coming to Ireland this year. It will be based at Cork Institute of Technology, running from 26 June to 25 August.
* International Symposium on Astronomy and Astrobiology Education: 3–8 July 2017; Utrecht, Netherlands. More Information: http://ise2a.uu.nl/
* IAA Solar Day, 6 August, WWT, Castle Espie, 2 - 5 p.m.
* 36th International Meteor Conference, in Petnica, Serbia, from September 21 to 24, 2017. For details contact the Local Organizing Committee at email@example.com
* International Observe the Moon Night, 28 October 2017. More Information: http://observethemoonnight.
18: Interesting Weblinks: (Disclaimer - Use of material herein from various sources does not imply approval or otherwise of the opinions, political or otherwise, of those sources). NB: If the title in the weblink does not indicate the subject matter, I give a brief simple intro before the link. I may also comment about the link afterwards.
20. JOINING the IRISH ASTRONOMICAL ASSOCIATION: This link downloads a Word document to join the IAA. http://documents.irishastro.
If you are a UK taxpayer, please tick the 'gift-aid' box, as that enables us to reclaim the standard rate of tax on your subscription, at no cost to you. You can also make a donation via Paypal if you wish: just click on the 'Donate' button. See also www.irishastro.org.