Category Archives: Radio

Pythagorean Astronomy: The Astronomer Royal and Potatoes on Mars


[Cross-posted from the Cardiff Physics Outreach blog]

April’s edition of our monthly astronomy podcast, presented by Chris North and Edward Gomez.

Earlier this month we were treated to a talk in Cardiff by Lord Martin Rees, the Astronomer Royal and Professor of Astrophysics at University of Cambridge. This afforded us the opportunity to speak to Professor Rees about the subject of his talk: “The World in 2015 – and beyond”. After discussing the challenges facing the long-term survival of humanity, and possible solutions, we also discussed Lord Rees’ role in the House of Lords, and recent developments in astronomy and cosmology. Continue reading

Pythagorean Astronomy: TRAPPIST-1 and other stories

TRAPPIST-1 artist impression

At the end of last month, there was a lot of interest in the discovery of seven roughly Earth-sized planets in the TRAPPIST-1 system. One month on, Chris North and Edward Gomez discuss the implications of this discovery. We also get an update from the Amaury Triaud, of the University of Cambridge, about TRAPPIST and its successor, SPECULOOS.

Here in our own Solar System, there’s the discovery of a cometary landslide from Rosetta, a milestone in wheel-wear on the Mars Curiosity Rover, and an update on some of Saturn’s darker rings from Japan. Further afield, a study of the rotation of galaxies in the distant Universe came under some scrutiny, shedding a bit of light on the process of scientific discovery.

An extended edition of the an original broadcast on 27th March 2017 as part of Pythagoras’ Trousers on Radio Cardiff.

For an archive of Pythagorean Astronomy, visit

Pythagorean Astronomy: Backyard Worlds


Artist’s impression of the proposed Planet Nine. Image Credit: Caltech/R,. Hurt (IPAC)

[Cross-posted from]

February saw the first launch of SpaceX’s Falcon Rocket from Launchpad 39A – the same launchpad used by the Apollo missions and the Space Shuttle. In this month’s Pythagorean Astronomy, Edward Gomez and Chris North discuss these impressive structures along with the study of a supernova (the explosive death of a massive star) just hours after it exploded, providing crucial insights into the very early stages of these extreme events.

A new Zooniverse project, Backyard Worlds: Planet 9, was also announced designed to let “citizen scientists” (i.e. you!) help track down Planet Nine – whose existence was seriously proposed a year ago. Project leader Marc Kuchner told us about that project.

For those wondering, we recorded this before the announcement of both TRAPPIST-1 and the SpaceX announcement of their planned lunar missions – but they’re pretty safe bets for discussion next month!

An extended edition of the an original broadcast on 27th January 2017 as part of Pythagoras’ Trousers on Radio Cardiff.

For an archive of Pythagorean Astronomy, visit

Pythagorean Astronomy: Star Attractions

Star Attractions. Image courtesy of National Museum, Cardiff

Image courtesy of National Museum Cardiff

Join Chris North and Edward Gomez as they discuss the month’s astronomy news. Not only were there two new NASA missions announced this month, but Space-X successfully returned to flight with their Falcon 9 rocket. Further afield, there are predictions of a pair of stars that are set to explode in a few years.

Being January, the National Museum in Cardiff hosted its annual public event celebrating all things space. With exhibits, demonstrations and shows for all ages, several thousand people attended “Star Attractions” and get to learn a bit more about astronomy and space. While we were there with a stand from the School of Physics and Astronomy, Chris spoke to a few people who were there to find out what they got out of it.

Originally broadcast on 30th January 2017 as part of Pythagoras’ Trousers on Radio Cardiff.

Pythagorean Astronomy: Assassin Supernova

artist's impression

Close-up of star near a supermassive black hole (artist’s impression) Image credit: ESO, ESA/Hubble, M. Kornmesser

When is a supernova not a supernova? The brightest supernova on record was discovered in 2015 by the All Sky Automated Survey for Supernovae (ASAS-SN). Named ASASSN-15lh, this remarkable event – what looked like a huge brightening of a star in a distant galaxy – was observed by many other telescopes, including the Hubble Space Telescope and the Las Cumbres Observatory network. With careful study, it became apparent that ASASSN-15lh was not quite what it seemed. Rather than being the explosion of a massive star, it is now thought that it was the final flash as a star was swallowed by a supermassive black hole.

This month, Morgan Fraser, from University College Dublin, and Las Cumbres Observatory’s Edward Gomez explain the story of this discovery – and rediscovery! We finish with a brief recap of 2016, and a look forward to 2017.

Originally broadcast on 19th December 2016 as part of Pythagoras’ Trousers on Radio Cardiff.

Pythagorean Astronomy: the GLEAM Survey


The GLEAM Survey

We’ve got a lot of news items to discuss this month. In the outer Solar System, Edward Gomez and I discuss the Cassini spacecraft, which has made its final major orbital manoeuvre, and the Juno spacecraft, which has had a few issues getting into its main science orbit. Further from home, we’ve got the first “official” star names from the International Astronomical Union, and the discovery of the roundest known star.

Our main guest this month is Dr Natasha Hurley-Walker, based at the International Centre for Radio Astronomy Research (ICRAR) at Curtin University. Natasha works on the Murchison Widefield Array, and has produced GLEAM: an all-sky image of the sky at radio wavelengths at very high resolution and in a wide range of radio “colours”, or wavelengths. This gives us a better understanding of some of the most energetic processed taking place in the centres of nearby galaxies, but the end goal is somewhat further afield. Natasha tells me all about the MWA, the GLEAM project, and even how you can view it – on the interactive GLEAMoscope site (or using the GLEAM Android app)

Originally broadcast on 28th November 2016 as part of Pythagoras’ Trousers on Radio Cardiff.

Pythagorean-Astronomy: ExoMars and Galaxies

A lot has happened this month – ESA got a spacecraft into orbit around Mars, but sadly lost the Schiaparelli lander, China launched two new taikonauts to their space station, and the Swarm mission uncovered details from Earth depths. Edward Gomez and I discussed these, and more, this month (though before the full nature of the status of the Schiaparelli lander were available).

In other astronomy news, a scientific paper hit the headlines claiming to have worked out how many galaxies there are in the observable Universe. Cardiff colleague Professor Steve Eales told me quite what he thought of this latest result…

Originally broadcast on 24th October 2016 as part of Pythagoras’ Trousers on Radio Cardiff.

Pythagorean Astronomy: Rosetta and OSIRIS-REx

Rosetta_at_comet_67P_landscape_1280This month sees the start of one mission and the end of another. NASA’s OSIRIS-REx mission launched at the start of the month to go and study asteroid Bennu, and even bring back a sample to Earth.

Meanwhile, the end of the month sees the finale of ESA’s Rosetta mission, which has spent two years studying comet 67P/Churyumov-Gerasimenko. With stunning images accompanied by fascinating results from other instruments, not to mention the plucky little Philae lander, Rossetta has been one of the most exciting missions of recent years.

This month, the Open University’s Professor Monica Grady tells me about comets, asteroids, and these two exciting missions.

Originally broadcast on 26th September 2016 as part of Pythagoras’ Trousers on Radio Cardiff.

[Cross posted from our Cardiff University School of Physics and Astronomy engagement site]

Pythagorean Astronomy: Mission Juno


Artist’s Impression of a Juno and Jupiter. Credit: NASA

In July 2016 NASA’s Juno spacecraft completed its five year journey to the planet Jupiter. On board is a suite of instruments and experiments that will provide exquisite insight into the history of our Solar System’s largest planet.

The process of Jupiter’s formation is a long-standing mystery that planetary scientists have been trying to answer for decades. As the University of Leicester’s Dr Leigh Fletcher explains, Juno will make careful measurements of Jupiter’s gravitational field and yield crucial information about its interior.

Originally broadcast on 28th July 2016 as part of Pythagoras’ Trousers on Radio Cardiff.

Pythagorean Astronomy: the Origins of Black Holes

GRO J1655-40 is the second so-called 'microquasar' discovered in our Galaxy. Microquasars are black holes of about the same mass as a star. They behave as scaled-down versions of much more massive black holes that are at the cores of extremely active galaxies, called quasars. Astronomers have known about the existence of stellar-mass black holes since the early 1970s. Their masses can range from 3.5 to approximately 15 times the mass of our Sun. Using Hubble data, astronomers were able to describe the black-hole system. The companion star had apparently survived the original supernova explosion that created the black hole. It is an ageing star that completes an orbit around the black hole every 2.6 days. It is being slowly devoured by the black hole. Blowtorch-like jets (shown in blue) are streaming away from the black-hole system at 90% of the speed of light.

Artist’s Impression of a black hole in a binary star system. Credit: ESA/Hubble

[cross-posted from Cardiff Physics Outreach blog]

On 15th June 2016 the LIGO collaboration released more detections of gravitational waves. As with the first detection, announced back in February, these gravitational waves were emitted by pairs of black holes, spiralling together and merging,

But of course, those black holes need to come from somewhere, and in this case it’s thought to be the deaths of some of the most massive stars in the Universe. To understand more about the deaths of massive stars, and the formation of black holes, I talked to Professor Stephen Smartt, from Queen’s University Belfast, who’s been on the hunt for black holes.

Originally broadcast on 30th June 2016 as part of Pythagoras’ Trousers on Radio Cardiff.