Astronomy To Africa - June 2016
The School of Physics and Astronomy is leading a new novel project to bring radio astronomy to developing countries in Africa. Prof Melvin Hoare has won a grant worth upwards of £650k, from a new government funding system called the Newton Fund. This utilises the government's Overseas Development Assistance (ODA) money to enable new scientific collaborations with developing countries.
Astronomy has long been known as a subject that inspires young people to take an interest in science and technology, which the project hopes to exploit to drive economic development. South Afruca is hosting its first big science project in the form of the Square Kilometre Array (SKA)- the world's next generation radio telescope. This is a project that Leeds astronomers are interested in due to the leap forward in potential scientific discovery it represents.Read More...
Expanding our view
As part of the first phase of this major international project over 200 dishes will be constructed in South Africa, which will be completed by 2023. The second phase is planned to extend the networkd of advanced radio antennas into eight African partner countries by around 2030. In the run ip to the full SKA South African engineers are currently constructing a network of more traditional radio dishes in the eight African partner countries called the African Very-Long-Baseline-Interferometry Network (AVN). These will be linked together to simulate a telescope the size of the continent and will deliver very high spatial resolution radio images.
In addition, students receive training in science outreach so they can go into schools in the partner countries to bring the excitement of astronomy to a large number of young people. These activities have the aim of increasing STEM take-up at all levels, which will, consequently, help grow the fraction of the population who are equipped to use this knowledge for economic development.
As well as providing in-country training the scheme is also funding PhD and MSc places in the UK. The first Kenyan student is about to start a PhD in radio astronomy at Leeds this year. These activities will enhance the international outlook of the School and could provide opportunities for undergradtuate involvement in Africa in related projects. Our industrial partners in this scheme include Goonhilly Earth Station Ltd., with whom Leeds is already collaborating on a related project. This joint project will see the repurposing of large 30m dishes on the ex-BT site in Cornwall for research and undergraduate training.
You can see Prof Hoare talking about his international research collaborations in Africa in the video below:
LSR Heart of Science: The Milky Way by Prof Rene Oudmaijer - April 2016
This week's guest on Leeds Student Radio's science discussion show was Prof. Oudmaijer discussing the Milky Way.
Leeds Researchers the First to Find a Keplerian-Like Disc around a Forming O-Star - October 2015
Observations led by astronomers at the University of Leeds have shown for the first time that a massive star, 25 times the mass of the Sun, is forming in a similar way to low-mass stars.
The discovery, made using a new state-of-the-art telescope called the Atacama Large Millimeter/submillimeter Array (ALMA), which is based in Chile, South America, is published online today by The Astrophysical Journal Letters.
Lead author Dr Katharine Johnston said: "Our groundbreaking observations show that not only does this still-forming massive star feed from a disk of material that surrounds it, like young Sun-like stars do, but it also mirrors low-mass star formation in the way the disk spins around the star."
See the full press release here.
LSR Heart of Science: The Life Cycle of a Star by Dr Stuart Lumsden - October 2015
Leeds Student Radio provides a weekly science programme discussing some of the biggest topics in science with academics from the university. This week it featured our very own Dr. Stuart Lumsden discussing the life cycle of a star.
Probing the Early Life of Planet-Hosting Stars - September 2015
Astronomers have successfully peered through the 'amniotic sac' of a star that is still forming to observe the innermost region of a burgeoning solar system for the first time.
Lead author Dr Ignacio Mendigutía from the School of Physics and Astronomy at the University of Leeds, said: "Nobody has ever been able to probe this close to a star that is still forming and which also has at least one planet so close in.
"We have been able to detect for the first time emission from the innermost part of the disk of gas that surrounds the central star. Unexpectedly, this emission is similar to that of 'barren' young stars that do not show any signs of active planet formation."See the original press release here.
Mining the Milky Way - May 2015
Leed Astronomers Release Results of New Radio Astronomy Survey
Astronomers have released the results from a new survey of the contents of the Milky Way as seen at radio wavelengths. The survey, led by Prof Melvin Hoare at the University of Leeds, was conducted with the Very Large Array in New Mexico and is the most detailed done to date. Radio waves have the advantage that they can be used to look right through the plane of our Galaxy without any obscuration from the clouds of interstellar material that affects other forms of radiation.
From the outset, the radio survey was conceived to compliment surveys being conducted at other wavebands. In particular, it matched the area covered by NASA's Spitzer satellite, which had already produced images an order of magnitude better than any previous ones in the infrared waveband. This co-ordinated approach was designed to give a comprehensive view of where all the stars much more massive than our Sun are being born in our Galaxy. Such stars form out of the gravitational collapse of large clouds of interstellar gas and dust that then gets heated to high temperatures by the newly formed star. The hot gas radiates strongly at radio wavelengths like a continuous hiss, whilst the hot dust emits in the infrared similar to the glow seen in thermal imaging cameras.Read More...
Given the multi-wavelength approach, the new survey is known as the Co-Ordinated Radio 'N' Infrared Survey for High-mass star formation or CORNISH survey. This also reflects the origins of Prof Hoare and fellow Cornishman and team member Prof Phil Diamond, who now heads the global team designing the world's next generation radio telescope, the Square Kilometre Array. The infrared satellite survey was led by Prof Ed Churchwell, of the University of Wisconsin, USA, who commented "Having matching radio data will really help us determine the nature of some of the tens of millions of infrared sources, whether or not they are detected in the radio".
A catalogue of over 3000 of the most reliable sources has been released online. About 10% of the sources are identified as the type of nebulae associated with the birth of massive stars similar to the famous nebula in Orion that can be seen with the naked eye. Prof Hoare says that "Having such a comprehensive sample of these objects across the Galaxy means that we can really start to test theories of how these stars form".
Understanding exactly how material accumulates onto these stars that can be a hundred times more massive than our Sun and put out a million times more radiation has challenged astronomers. Although these stars are rare their prodigious output of energy can drive the evolution of whole galaxies. In addition to studying the birth of massive stars, the combination of radio and infrared studies is also good for a systematic census of the death of stars similar to our Sun. When our star begins to run out of fuel in five billion years' time its outer layers of gas and dust will be ejected and heated by the hot core left behind. Newly discovered examples of these so-called planetary nebulae are also a significant population among the sources in the new radio survey. Other examples of radio emitting star-like objects have been found that are completely unknown. Mining this new resource will keep the thirty-strong international team from around the world busy for years to come.
The above image shows an example section of the Milky Way surveys in the infrared (image) and radio (green contours in insets) showing three very different types of sources. In the middle is a region where massive stars are being born where it appears that the pressure from an older, larger nebula has caused the formation of a younger, smaller radio source. On the left is an example of the other end of stellar life where a star like our Sun is ejecting its outer layers in a bipolar nebula and the hot stellar core is heating up the gases to give rise to the radio emission. The radio source on the right is not in the Milky Way at all, but a very distant radio galaxy powered by a super- massive black hole. Such objects are not seen in the infrared.
Links for more information: