Not all telescopes capture visible light. Dr Josh Reynolds, a lecturer in the Department of Physical Sciences in MTU, told us about VERITAS – a ground-based very high energy (VHE) gamma-ray instrument. It operates at the basecamp of the Fred Lawrence Whipple Observatory 1.3 km above sea level in southern Arizona USA, and consists of four 12 m Imaging Atmospheric Cherenkov Telescopes (IACT) which use Cherenkov shower imaging to detect gamma-ray photons with energies above 85 GeV.
Josh covered the history and science of VERITAS along with a personal account of tours of duty to the observatory as a VERITAS collaborator, and didn’t neglect to tell us about the poisonous toads that inhabit the site.
The lecture wase live streamed over Zoom.
About Dr Josh Reynolds
Dr Reynolds has been a member of the VERITAS collaboration since its inception in 2003 (as well as being a member of it progenitor, the Whipple Observatory collaboration) and a co-author of the publication that announced the discovery the Atmospheric Cherenkov Imaging Technique in 1989. He also lectures in the Department of Physical Sciences in MTU.
More about VERITAS
VERITAS (Very Energetic Radiation Imaging Telescope Array System) is an international astrophysics collaboration between the USA, Canada, Ireland and Germany, involving 9 founding institutions and 15 collaborating institutions (MTU is a collaborating institution). It operates a ground-based gamma-ray instrument at the Smithsonian Institution’s Fred Lawrence Whipple Observatory (FLWO) in southern Arizona, USA. This is an array of four 12m optical reflectors that uses the Imaging Atmospheric Cherenkov technique to perform gamma-ray astronomy in the GeV-TeV energy range. Very High-Energy gamma rays are associated with exotic cosmic objects such as supernovae, pulsars, quasars and black holes. Expensive, space-based observatories are normally required to detect gamma rays as they are absorbed in the atmosphere, but VERITAS is able to use the Atmospheric Cherenkov Imaging technique to observe them from the ground. VERITAS has a prodigious research output, with 162 publications in peer-reviewed journals (44 over the last 5 years) including publications in Science, Nature and Nature Astronomy.
The James Webb Space Telescope (JWST) is on the lips of every astronomer. Dr Niall Smith of MTU and the brains behind Cork’s Blackrock Castle Observatory told us why. Launched on Christmas Day 2021 JWST is sending back images of the universe in previously unimaginable detail. Crucially this telescope observes in the infrared, which is necessary when observing the early universe. Early means far away and moving fast from us, thus extremely red-shifted, hence undetectible in the visible spectrum where the Hubble Space Telescope operates. JWST will supply new information about the early universe, indeed already has done, which will change our knowledge of how it all began and where it’s headed.
One of our favourite speakers, we were delighted to welcome Niall to launch our new season of monthly lectures, which after a long Covid-induced absence, will once again be held in our old home of University College Cork’s Civil Engineering building.
About 20 visitors gathered with Club members on Saturday 9th April for a demonstration of how to view sunspots. The Sun is currently in an active phase of its 11-year cycle – although sadly today sunpsots were scarce … but that’s astronomy!
We brought specialist equipment, and showed how we observe and image solar spots and other features, and explained how they take 14 days to move across the face of the Sun. Visitors saw how the Sun looks different in optical wavelengths or hydrogen-alpha. The image above was taken by Club member Jan on 3rd April.
NEVER VIEW THE SUN (EVEN THROUGH CLOUDS) WITHOUT SPECIALIST EQUIPMENT UNDER GUIDANCE OF AN EXPERT
The event lasted two hours, was was part of Cork’s Lifelong Learning Festival.
Cork Astronomy Club welcomed prominent Northern Ireland amateur astronomer Paul Evans, maker of highly regarded monthly sky guide videos, and Chair of the Irish Federation of Astronomy Societies. Paul spoke to us remotely by Zoom
Since the Solar System is essentially flat, though crucially not quite flat, it does occasionally happen that viewed from Earth, one object will pass in front of or behind another. Some of these events are of technical interest while some are truly spectacular celestial events.
Paul described some personal experiences of past events and pinpointed some opportunities for events in the future to look forward to.
Like many of his generation Paul was inspired by the Apollo Moon missions and it was Apollo 8 which really piqued his lifelong interest in space and astronomy.
Originally from England, though his mother is from Athlone, Paul has lived in Northern Ireland since 2003 during which time he has photographed auroras, noctilucent clouds and many sky objects. His photographs have been displayed in numerous exhibitions and publications in Britain and Ireland.
Paul is a past President of the Irish Astronomincal Association and has been Chair of the Irish Federation of Astronomy Societies (to which our Club is affiliated) since April 2019.
Cork Astronomy Club was honoured to welcome Dr Ann-Marie Madigan, Assistant Professor of Astrophysics at University of Colorado, Boulder. There’s something odd going on in our solar system, and presence of a new planet (‘planet 9′) or a black hole have been proposed to account for it, but Dr Madigan has other ideas.
Prof Madigan’s favoured explanation is a new Kuiper belt, further out than the actual Kuiper belt, and containing about 10 Earth masses of material. If found, will it be called the Madigan Belt? You heard it here first.
Dr Madigan explained: While the planets move on nearly-circular orbits in a disk, the icy bodies beyond Neptune appear to cluster together in a highly-inclined and eccentric structure. Astronomers have invoked the presence of a new planet (‘planet 9′) or even a black hole in explanation!
In her talk she showed that these theories are unnecessary. In analogy with spiral arms and bars in galaxies, the collective gravity of individually small but collectively massive bodies can create such structure in the outer solar system. This explanation predicts that there is a (highly-inclined) disk of minor planets, more massive than the Kuiper Belt, awaiting discovery at the edge of our solar system.
To open our 2021-22 season of public lectures, Cork Astronomy Club welcomed Dr Robin Catchpole of the Cambridge Institute of Astronomy. He talked to us via Zoom.
The title of his lecture was “Taking the Measure of Our Universe”. Two thousand years after the ancient Greeks thought of the idea, we measured the distance to the nearest star. Less than two hundred years later we are measuring the distance to a 1000 million stars almost a million times more accurately, opening a new era of discovery in astronomy. Soon we will measure the position of 3000 million galaxies in the hope that they might reveal the nature of the mysterious dark energy. Robin explained how this is being done and what more we know about our universe.
One member commented: “Robin was an amazing lecturer and had me spellbound.”
Now an astronomer at the Institute of Astronomy, Cambridge, Dr Catchpole has held posts at various observatories around the world including Senior Astronomer at the Royal Observatory Greenwich.
He has authored and co-authored over 120 research papers and articles and used a number of telescopes including the Hubble Space Telescope. Research interests include the composition of stars, exploding stars, the structure of our Galaxy and galaxies with black holes at their centres. His current research interest is in the structure of the Bulge of our Milky Way Galaxy.
Cork Astronomy Club welcomed Cork-based electronics engineer Cillian O’Driscoll who drew on his work with ESA on the Galileo project, Europe’s own global navigation satellite system, to review how satellites have changed the way we navigate the globe. The lecture was held via Zoom.
Fantastic talk from someone who clearly is a master of his subject, was the verdict of one member in the audience.
Cillian explained the mechanics of GNSS systems (that’s any satellite navigation system with global coverage) and answered many detailed questions from members. He also delved into the political ramifications. The Galileo system is a project of the Europe Commission, he explained, although the technical work is contracted to ESA. In the early 2000’s the US government was keen to discourage Galileo and to persuade the EU to be satisfied with GPS, which is under US military control, and used to have a built-in 100m error margin.
For our final lockdown lecture of the current season, Cork Astronomy Club welcomed Society for the History of Astronomy Chairman Gerard Gilligan to tell us about William Lassell, the Liverpool brewer and amateur astronomer who in 1846, using his own self built telescope, discovered Neptune’s largest moon, Triton, just 17 days after the discovery of Neptune itself.
Amanda Bauer, Head of Education and Public Outreach at Vera C Rubin Observatory, joined us by Zoom from Tucson Arizona to tell us about a sizeable telescope due to commence operations in Chile at the end of 2022 which will open a bigger window on the universe and allow citizen scientists to download an app and contribute to analysing data.
The Vera C. Rubin Observatory will conduct the 10-year Legacy Survey of Space and Time (LSST) starting in late 2023. It will survey the southern sky every 4 nights and record every change – what dims, what brightens, what moves or disappears. We’ll see the universe in action! Citizen scientists can join in. One comment was “if the rest of the team are even half as enthusiastic, it’ll be finished ahead of time!”
LSST will deliver a 500 petabyte set of images and data products that will address some of the most pressing questions about the structure and evolution of the universe and the objects in it. Rubin Observatory has an outreach team designing and building an innovative, modern, and inclusive program. Amanda demonstrated a prototype online astronomy investigation and highlighted citizen science opportunities with LSST data.
Calendars, clocks, and how the measurement of time links to the Earth and the solar system were Prof Malone’s theme when he joined us by Zoom from Maynooth University. He called his talk “How to tell the time” and time was the one thing lacking, the question session lasting 25 minutes after the meeting was meant to close. David Malone is a mathematician on the staff of Maynooth University’s Hamilton Institute
A little nugget of information was that the word “minute” comes from the Latin pars minuta prima, meaning “first small part”. This division of the hour can be further refined with a “second small part” (Latin: pars minuta secunda), and this is where the word “second” comes from.