The first IYA2009 Cornerstone Project brings the stars to Liverpool

05-June-2008, Liverpool: A prototype exhibit of astronomy images called From Earth to the Universe is a precursor of the wide range of events planned in celebration of the International Year of Astronomy in 2009. The dazzling display of images will take viewers deep into the Universe from 7-29 June 2008 and will be held at the Albert Dock in Liverpool, UK.

Original content here. With the International Astronomical Union (IAU) and UNESCO’s International Year of Astronomy 2009 (IYA2009) nearly upon us, the Albert Dock in Liverpool will host the first event displaying breathtaking images from an IYA2009 Cornerstone project, From Earth to the Universe. This majestic photographic display, which is planned for 7-29 June 2008, takes viewers on a colourful visual journey through the wonders of the Universe and allows them to travel back through 13 billion years across the evolving Universe. The 48 images were created by some of the world’s best astrophotographers — professionals as well as hobbyists, while the display was generated by a collaborative task group that includes members from the European Southern Observatory and NASA’s Chandra X-ray Center. Liverpool was chosen to host the exhibit because it is the European Capital of Culture during 2008 and will also play host to a major European astronomy meeting this month. “We are delighted to be displaying such magnificent pieces of photography at the Albert Dock,” said Joe Edge, director of Albert Dock. “As 2008 marks such a huge year for Liverpool, people from all around the world will be visiting the Dock and this display gives them the chance to see something unique in an unusual setting.” As stunning as the current display is, it is merely a prototype for the exhibit that will be shown in non-traditional public venues such as parks and gardens, shopping malls, metro stations and airports in major cities across the world next year. The goal in the IYA2009 is to engage individuals who might normally ignore or even dislike astronomy or science in general. The exhibition is sponsored by the world’s leading specialist picture agency, the Science Photo Library, and co-sponsored by ASTRONET. The exhibition manager for the Liverpool IYA2009 From Earth to the Universe exhibition, Gary Evans from the Science Photo Library, says: “This exhibition is probably the first real IYA2009 event and we are very proud to be hosting it in the UK. We simply could not wait for 2009 and took advantage of Liverpool’s status as the European Capital of Culture during 2008.” Jean-Marie Hameury, the ASTRONET Project Coordinator says “The timing of the exhibition was also set to coincide with the large ASTRONET Infrastructure Roadmap. Here a concise European plan for the next 15-20 years of astronomy will be presented — an important milestone for astronomy in Europe. The public will be thrilled to know that, as they marvel at what astronomy has achieved so far, its future in Europe is being decided right next door”. With eleven Cornerstone projects well underway, the IAU has many more plans for 2009. The Union aims to celebrate astronomy’s contributions to society and culture and to stimulate worldwide interest in astronomy through the creation of interactive networks. The vision is to help the citizens of the world rediscover their place in the Universe through the day and night time sky – and thereby engage a personal sense of wonder and discovery. Everyone should realise the impact of astronomy and basic sciences on our daily lives, and understand better how scientific knowledge can contribute to a more equitable and peaceful society. Events and activities held throughout the year will further promote a greater appreciation of the inspirational aspects of astronomy that embody an invaluable shared resource for all nations. The IYA2009 Cornerstone projects will engage individuals through multiple media forms, from hands-on observations of the night sky in the Galileoscope project to virtual blog interactions with practicing astronomers through the Cosmic Diary project. Projects like She is an Astronomer will also address diversity problems within the astronomical community, such as the continued role of gender inequality, while projects like Universe Awareness will focus on sharing the wonders of astronomy with young, disadvantaged children. With all of the preparations underway for next year’s events, IYA2009 is shaping up to be an incredible experience for individuals around the globe.

FETTU Exhibition in Liverpool.Credit: IYA2009 and FETTU. [TIF 13.87MB] Panel: Hercules Globular Cluster and the Pleiades. Credit: IYA2009, FETTU and Robert Gendler. [TIF 1.07MB] Panel: Solar Corona and Coronal Loops. Credit: IYA2009, FETTU, SOHO/EIT consortium of NASA and ESA, Trace Team of the Stanford-Lockheed Institute for Space Research, NASA. [TIF 878 KB] Panel: Antennae Galaxies, Cartwheel Galaxy and Fornax A. Credit: IYA2009, FETTU, NASA/ESA, P. Appleton, JPL-Caltech, J. Uson, NRAO/AUI and Palomar Sky Survey. [TIF 790 KB]

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Notes for editors

 

• • To learn more about IYA2009 and the Cornerstone projects, please visit: http://www.astronomy2009.org/

• • The IYA2009 activities will take place at global and regional levels, and especially at the national and local levels. National Nodes in each country have been formed to prepare activities for 2009. These Nodes establish collaborations between professional and amateur astronomers, science centres, educators and science communicators in preparing activities for 2009. The International Year of Astronomy (IYA2009) was proclaimed by the United Nations on 20 December 2007.
• • The IAU is the international astronomical organisation that brings together almost 10 000 professional astronomers from all nations of the world. Its mission is to promote and safeguard the science of astronomy in all its aspects through international cooperation. The IAU also serves as the internationally recognised authority for assigning designations to celestial bodies and the surface features on them. Founded in 1919, the IAU is the world’s largest professional body for astronomers. To learn more about IAU, please visit: www.iau.org
• • A public lecture, “How Astronomers Image the Sky,” will be given by­ Robert Fosbury of the Space Telescope-European Coordinating Facility in association with the exhibit. The lecture will be held at the Chadwick Lecture Theatre at the University of Liverpool at 18:30 on 19 June and is being co-sponsored by the Institute of Physics and the Royal Astronomical Society. For more information, please visit: http://www.astro.ljmu.ac.uk/~airs2008/PublicEvents.html
• • A selection of images from exhibition can be downloaded at www.fromearthtotheuniverse.org/liverpool.php and can be used free of charge.
• • Prints of all images in this exhibition are available to purchase from www.sciencephotogallery.co.uk from 9 June 2008 onwards.
• • Science Photo Library (SPL) is the world’s leading specialist picture agency with a collection of more than 250,000 images. Although SPL covers all areas of science, from aerodynamics to zoology, the company is particularly proud of its very long history of working closely with astronomers and astrophotographers. SPL represents several of the most prestigious multinational observatories in the world, and works alongside the scientists of NASA and the European Space Agency. To learn more about Science Photo Library, please visit www.sciencephoto.com
• • ASTRONET was created by a group of European funding agencies in order to establish comprehensive long-term planning for the development of European astronomy. The objective of this effort is to consolidate and reinforce the world-leading position that European astronomy attained at the beginning of the 21st century. The ASTRONET Symposium is being held 16-19 June and is hosted by Liverpool John Moores University. To learn more, please visit www.astronet-eu.org
• • The Albert Dock in Liverpool is the largest grouping of Grade I listed buildings in Britain. With around four million visitors each year, the Dock is the most visited, multi-user attraction in the UK outside London. Today the Albert Dock consists of over 25 retail shops and has several unique visitor attractions, such as: Tate Liverpool, the Beatles Story, and Merseyside Maritime Museum. To learn more, please visit www.albertdock.com
• • To learn more about Liverpool, the European Capital of Culture 2008, please visit www.liverpool08.com

For more information, please contact:

 

Liverpool From Earth to the Universe Exhibition manager
Gary Evans
Manager, Scientific Relations, Science Photo Library, London, UK
Tel: +44-(0)20-7432-1100
Cellular: +44-(0)-7970-287923
E-mail:  gary.evans@sciencephoto.com

 

From Earth to the Universe Co-Chair
Megan Watzke
Public Information Officer, Chandra X-ray Observatory, Cambridge, USA
Tel: +1- 617-496-7998
E-mail:  mwatzke@cfa.harvard.edu

 

IAU Press Officer/Secretary of IAU IYA2009 Executive Committee Working Group
Lars Lindberg Christensen
ESA/Hubble & IAU, Garching, Germany
Tel: +49-89-32-00-63-06
Cellular: +49-173-3872-621
E-mail:  lars@eso.org

 

IYA 2009 Secretariat
Pedro Russo
IAU & ESA/Hubble, Garching, Germany
Tel: +49-89-320-06-195
Cell: +49-176-61100211
E-mail:  prusso@eso.org

UNESCO Contact
Yolanda Berenguer
Space Education Programme Coordinator
UNESCO HQ, Paris
Tel: +33-1-45684171
E-mail:  y.berenguer@unesco.org

Astronomers Predict Nearby Stellar Fireworks by Mid-Century

Astronomers are announcing today the prediction that the bright northern star called epsilon Aurigae is headed for a “doomsday event” within a few decades. The report is being presented by Dr. Robert Stencel, of the University of Denver Observatories in a press conference today at the American Astronomical Society meeting in St. Louis, Missouri. Observations over the coming three years, when the mysterious star undergoes a once-per-generation eclipse event, may hold the secret to the extreme changes detected during the past few decades.

Contact information: Dr. Robert Stencel, Professor of Astronomy, University of Denver 303-871-2135 – rstencel@du.edu – http://www.du.edu/~rstencel

The Science Case: What could be simpler than an eclipsing binary star? As they orbit each other, it is relatively easy to measure brightness change and the duration of change, and, from simple geometric arguments, to obtain size and temperatures for each star in the binary. With the addition of Doppler spectroscopy, which measures orbital velocities, one can solve for mass of each star, using Kepler’s third law.

The classic example of this is the so-called Demon Star, Algol, which exhibits 2 hour eclipses every 2.87 days. With such eclipsing binary stars, astronomers can calibrate important parameters that describe a star’s structure. The Vogt-Russell theorem says the mass, composition and age uniquely determine the stellar structure, when normal laws of physics are applied. This theorem appears largely true, except for epsilon Aurigae – the real “Demon star”. It’s behavior has “bedeviled” astronomers for centuries.

The spectrum of epsilon Aurigae looks like a normal F supergiant star, estimated at about 12 to 15 times the mass of the Sun. The orbit data implies that the mass ratio in the binary is close to one, implying that the companion is about 12 to 14 solar masses as well. Epsilon Aurigae exhibits Algol-like eclipses every 27 years, which last for nearly 2 years. The next one starts in August 2009, and should run through May 2011.

The problem? The 12 to 14 solar mass second “star” is largely INVISIBLE! The best model (Huang, 1965) says the secondary is a huge dark disk, not a sphere. Such a shape needs a massive central object(s) to stabilize it.

Normal eclipsing binary star analysis suggests that the secondary is about 10 A.U. across (10 times the distance from the Earth to the Sun, or 930 million miles). It does not emit anywhere near the amount of light expected from a star of its size. Scientists are confident that it is not a black hole, because it hasn’t been detected with X-ray observations (Einstein, Swift).

Epsilon Aurigae shows low amplitude quasi-periodic light variations, similar to Cepheid variable stars. Cepheid variable stars are close relatives of epsilon Aurigae, being high mass yellow stars prone to pulsation – a useful property in terms of their Period-Luminosity relationship. Currently the light variations in epsilon Aurigae are on a 67 day cycle, but -KEY POINT- these were nearer to 95 days during the last two decades. Something is accelerating in this system! At this rate, variations will become very rapid within six decades, perhaps cataclysmically so. Much of the relevant photometric data has been obtained by Jeff Hopkins of Phoenix Observatory, Arizona (here), Il-Seong Nha of the Yonsei University Observatory, Korea and other observers (see here).

But wait—there’s more. Observations made during the last eclipse suggest that the F supergiant star may be shrinking by about 1/2 percent per year (noted in 1986 by Mamuro Saito and Masatoshi Kitamura at Tokyo Astronomical Observatory – here). The duration of total eclipse (during which the F star is partially covered by the disk shaped companion) has increased by about 25 percent between the 1956 and 1983 eclipses. Despite this, the overall length of the total plus partial phases of eclipse – especially the time where the F star moves out from the cover of its partner – has gotten shorter!

If these trends continue, the F star will come out of eclipse (from totality) in only 1 or 2 weeks during 2011. BUT, it will still take 140 days or so to move from the beginning of the eclipse to totality next year, autumn. What is changing, and what do the variations mean? Is this binary system preparing for an energetic event?

Is the light variation due to changes in the F supergiant star’s radius or temperature? Using the well-known correlation among stellar luminosity, radius and temperature, a ten percent change in Luminosity can result from a 5 percent change in Radius, or a 2.5 percent change in Temperature. At an estimated distance of 625 pc, and assuming the F supergiant star is close to the nominal 100 solar diameters appropriate for its type, then the implied angular diameter is 3 milli-arcseconds. Modern interferometers, like the Palomar Testbed Interferometer (PTI, San Diego County, CA), are capable of measuring down to fractions of one milli-arcsecond, close to that 5 percent change anticipated, and these measurements are underway. These measurements would help confirm that the F star could be causing the accelerating light changes.

What’s a milli-arcsecond? Astronomers use angular measures much finer than degrees on a protractor. The arc-second is 1/3600 part of one degree, and a milli-arcsecond is 1000 times finer. A 25 cent US coin seen at a distance of 6,500 miles (10,000 km) subtends about one milli- arcsecond.

The best model for the eclipsing object makes a clear, testable prediction that is suitable for interferometry: the F supergiant star shoulc be BIFURCATED (cut in half) by the eclipse-causing disk, if indeed it is a disk. Next generation imaging interferometers like CHARA at Mt.Wilson and MROI at Socorro, should be easily able to monitor this set of changes. If the disk is causing all of the changes in the system, that should be detected with these measurements.

In summary, the bright northern star, epsilon Aurigae, is exhibiting rapid changes suggestive of dramatic events within one or two eclipse cycles, later this century. As Stencel says, “These changes offer a chance to examine the dynamics of rapidly changing stellar disks on a human timescale, and an opportunity for the public to see for themselves that stars change.”