Solving the mystery of nitrogen throughout the Universe

Researchers in the E.A. Milne Centre for Astrophysics at the University of Hull have made a breakthrough in solving the mystery of the origin of nitrogen, one of the most important elements for life in the Universe.

The study, led by Dr Marco Pignatari with Professor Brad Gibson, PhD student Chris Jordan and scientists from across the world, analysed fossils of stars that died before the Sun was formed, to discover how nitrogen was produced.

The research is published in the leading academic journal, Astrophysical Journal Letters.

Dr Pignatari said, “Nitrogen is an element fundamental for our life, but we do not yet have a good understanding of how it was made in stars in different epochs of the Galaxy.”

“Furthermore, its isotopic composition observed in the solar system does not match with what theoretical stellar models have predicted so far. We were clearly missing something, it was a mystery.”

The work of the research team may have finally solved this unknown.

Over the last 30 years, a huge number of different types of anomalous dust particles have been identified in old pristine meteorites. Their chemical composition, analysed in a laboratory, found that it does not belong to the solar system.

The analysis of the unknown particles suggested that the small grains originate from a time before the Sun (presolar), and condensed around old stars that died.

A presolar silicon carbide grain mounted on a gold foil. Credit: R. Trappitsch, Chicago Center for Cosmochemistry, The University of Chicago

Because of their peculiar abundance, some of this dust has been identified as relics of ancient massive supernovae – massive explosions of stars.

The interpretation of their signatures can provide the most direct information about how these spectacular explosions work.

The analysis of the presolar dust not only gave the researchers insight into supernova explosions, but also what happened to their parent star before the explosion.

The conditions in these stars were found to be more extreme and complicated than what was expected, with mixtures of hot stellar matter with colder material coming from the outside.

Pignatari said, “It is like dropping cold water on a frying pan just out from the cooking plate. Something similar happened in stars, allowing nuclear reactions to make a lot more nitrogen, including its more elusive and rare stable isotope. This is exactly what is needed to explain observations, in the early galaxy and in the solar system.”

Dr Pignatari believes these exciting first results are just the beginning, and more research and new discoveries will continue at the E.A. Milne Centre.

Dr Pignatari said, “Presolar grains have much more to tell about supernovae and what elements they made. They gave us a lead to follow, and at the Milne Centre we will pursue that lead until the end of the trail.”

Top image: Hubble sees a spiral galaxy’s brights and darks. Image credit: ESA/Hubble & NASA and S. Smartt (Queen’s University Belfast); Acknowledgement: Robert Gendler

Launch of new astrophysics centre at University of Hull

This article was originally published by the University of Hull’s press office.

Cutting-edge research in astrophysics has been given a major boost with the opening of a dedicated centre at the University.

The E.A. Milne Centre for Astrophysics, named in honour of the Hull-born physicist and mathematician Edward Arthur Milne, will officially open this week.

Around a dozen members of the astrophysicist’s family have travelled from across the world to be in Hull for the opening, on Friday.

The centre’s aim is to take a fresh and dynamic approach to the big questions that have fascinated humankind for thousands of years.

Arthur Milne aged around 30

Professor Brad Gibson, director of the centre, said: “Astrophysics is one of the most exciting and powerful enablers of science, technology, engineering, and maths, and that grass-roots attraction is what has led the University to invest strategically and significantly in this area.

“We wanted the research, teaching, and public engagement activities in astrophysics to have a focal point around which to rally, and the realisation that one of the great scientists of the 20^th century – Arthur Milne – was born, raised, and schooled in Hull, at Hymers College, provided a unique opportunity.

“Working closely with Milne’s family, we laid out a plan to establish a strong regional presence in the field.  In a very brief period of time, we have grown from nil, to now have 14 staff and postgraduate students.”

Current research spans the physics of the sun through to the origin of the largest structures in the universe, as well as an investigation into the locations within the Milky Way galaxy most likely to harbour complex biological life.

Prof Gibson said: “The Milne Centre’s staff have been drawn from across the globe, cementing its international flavour and reputation, including the Ukraine, Australia, Italy, Germany, Thailand, and of course, the United Kingdom.”

Family members of Arthur Milne, including daughter Meg Weston Smith, grandchildren and cousins are travelling from as far away as Australia to be at the launch of the Centre on Friday, which will be held at the Art Gallery of the University of Hull’s Brynmor Jones Library.

Amongst the 70 guests will be the Deputy Lord Major of Hull, Hull East MP Karl Turner, representatives from the Royal Navy, and the President of the Royal Astronomical Society – a post that Milne himself held during World War II.

Physics courses at the University have a 100 per cent student satisfaction rate, according to the to the 2015 National Student Survey. The department also topped the Guardian University Guide 2016 when it comes to ‘Added Value’, which compares students’ degree results with their entry qualifications, scoring a maximum 10 out of 10.

Graduates are in high demand across a variety of industries, with many establishing successful careers in some of the world’s best-known laboratories and research facilities.

For more information about the E.A Milne Centre for Astrophysics, visit www.hull.ac.uk/milne

Professor Appointed to Joint Institute for Nuclear Astrophysics Advisory Committee

Professor Brad Gibson, Director of Research in the Department of Physics and Mathematics, has been appointed to the international advisory committee of the Joint Institute for Nuclear Astrophysics (JINA).

JINA brings together diverse physicists’ expertise from around the world to address open scientific questions in nuclear physics and astrophysics.

Professor Brad Gibson‘s role on the committee will utilise his unique and specialist knowledge in the field of galaxy physics and the chemical evolution of galaxies.

Professor Brad Gibson

Professor Gibson’s work in the field of galactic chemical evolution led to his development of an advanced suite of software which is now an industry-standard tool.

Using this software, Professor Gibson determined the likely locations in the Milky Way harbouring complex biological life, research that was acknowledged by National Geographic magazine as one of the top news stories of the year.

Professor Gibson said, “JINA is the driving force behind the world-wide effort aimed at pinpointing the origins of all the chemical elements. To be appointed to their International Advisory Committee and share responsibility for shaping the research priorities for the community is a truly surprising honour.”

Professor Gibson’s appointment comes ahead of the official opening of the University of Hull’s new E.A. Milne Centre for Astrophysics on 16^th October, of which Professor Gibson is Director.

Professor Dan Parsons, Associate Dean for Research in the Faculty of Science and Engineering said, “This is fantastic news for the Faculty and the University and great recognition for the dynamic astrophysics grouping at Hull led by Professor Gibson.”