Way, way back in the early epochs of Syzygy (ep 19 in Oct 2018 if you must know) we talked about the exciting prospect of spotting the first exomoon — a moon orbiting a planet orbiting a star that is not our own. It seemed reasonable to expect that six years later exomoons would be a thing we've discovered, and maybe even started a catalogue. But turns out, observing a minute signal on top of an already minute signal is hard. Emily outlines our best prospects for exomoon discovery.

A short announcement: Syzygy is now seasonal! From now on we're going to release the podcast in seasons, and we're excited to announce the imminent release of the first episode of Syzygy Season Two. Yep. Two. Season One is everything we've done so far. Trust us, it's easier this way. Season Two is all about Exo-Stuff — exo-planets, exo-moons, exo-comets ... are they a thing? Apparently, yes. So keep an eye out in the days ahead for the new season of Syzygy.

Live from York's Festival of Ideas*, in front of an audience of ... what, had to be a few hundred thousand people, right? ... Emily and Chris discuss some awesome astronomy that you can go outside and see with your own eyes. In particular, they go deep on the incredible May 2024 aurora, and show what the 2024 total eclipse across the USA looked like, with a preview of amazing eclipses to look forward to in the coming years. Chris finishes with a song, as he does. (* Apologies for the audio...

A huge team of astronomers — and their even-huger team of tiny, fibre-obtic-wielding robots — are zeroing in on one of the great questions of cosmology: just what the heck is going on with Dark Energy? We know the Universe is expanding. Apparently, it's expanding faster. But maybe it is expanding faster, slower? Tiny robots measuring breathtakingly-huge cosmic bubbles may give us an answer.

This week, a new Black Hole Record (kinda), and with it a nice conundrum. the GAIA mission has found the biggest black hole ... of the stellar-mass variety ... in our galaxy. A lot of caveats there, but the fun thing is, it's just next door, which makes us wonder if that's coincidence or a harbinger of more big black holes to come in GAIA's data dumps! Plus, a riddle: why do we keep spotting black holes that are too big to make? Did we break physics? Emily has a few explanations.

We're live from the 10th birthday celebrations for the University of York's Astrocampus, Emily's home turf and all-round fabulous teaching and outreach space. Emily fields some amazing questions from kids and adults attending the event, and gives some of Astrocampus's highlights and achievements over the past decade, as well as some plans for the future!

After some lengthy follow-up (the Bennu sample is open at last! And SLIM is alive!), Emily investigates possibly the most podcasty story we’ve had on the show: six planets around distant star HD110067, all locked into resonances that play beautiful music. Turns out if you leave a planetary system alone for long enough, gravity tends to pull everything into simple harmonies. Maybe our own solar system has a song to sing in the far future?

Emily and Chris tune in to JAXA’s livestream of SLIM — the Smart Lander for Investigating and Moon — as it attempted to slick the landing on the lunar surface on Friday 19 January 2023. We were prepared for success and champagne, or failure and lessons-learned. What we didn’t expect was … ambiguity, uncertainty and WE ARE STILL CHECKING THE STATUS SO PLEASE WAIT. Did SLIM and its fabulous little transformer rovers make it to the Moon OK or not?! Join us for all the anticipation, the wonder,...

Long-time Syzygy listener Jack asks: "Hey Emily — what's the deal with quasi-stars?" (We're paraphrasing). Quasi-stars are hypothetical, enormous stellar-object-thingies that might have formed shortly after the Big Bang. They're so huge they might have formed with black holes at their cores. If they existed at all, it would explain why astronomers keep finding intermediate-mass black holes in gravitational wave experiments. And as a bonus for you, Jack, Emily presents Hawking stars: otherwise...

Astronomers routinely detect cosmic rays, the high-energy particles from space that collide with molecules in the upper atmosphere, creating a shower of secondary particles that rain down on the earth below. But every so often — like, less than once a decade — they spot a cosmic ray smashing into the planet with just stupid amounts of energy. The sort of energy you associate with hitting a golf ball or maybe dropping a brick on your foot, but definitely NOT a single subatomic particle. Not...

We've talked BOATs before — cosmic events that are the Brightest Of All Time — and it's always a favourite topic on the show. Recently astronomers analysed the runner-up BOAT in the Burster category, an astoundingly violent, weirdly long-lasting, and oddly-located neutron star merger, and measured the amount of afterglow Tellurium to learn more about fast neutron processes. What?! As Emily patiently explains, with a brief cameo from Tom Lehrer, it's all about a deeper understanding of where...

We love it any time a listener gets in touch — but the *best* is when a listener suggests a topic for an episode of the podcast. So when Zofia Szczesna got in touch (through the Syzygy website, natch) and asked about white dwarf stars, Emily put her research hat on and dug into the amazing astrophysics of these amazing little entities. In this episode she lists her three favourite things about white dwarfs: a cheeky supernova loophole, wibbly-wobbliness, and our white dwarf (or more...

JWST is flinging out Just Wonderful observations at great speed, many already leading to new astronomical insights. Here's one that was really unexpected: the Orion Nebula is full of JuMBOs! Jupiter-Mass Binary Objects, that is — pairs of giant planets (or planetty-things, the definition isn't terribly clear ...) floating free in space, in quantities that aren't possible based on what we *thought* we understood about planet formation. New observations that seem to break astrophysics? We're...

Earth got a special delivery recently: a little pod plonked down in the Utah desert, containing a few hundred grams sampled from the surface of an asteroid. This isn't the first sample return mission, but it's definitely the biggest. The little parcel of asteroid dirt inside is now being very carefully handed out to researchers across the globe, and we're going to learn loads of important stuff, like what asteroids are made of, how we might stop one from hitting us ... and even, maybe, just...

It’s always nerve-wracking waiting for a very expensive new space telescope to launch — the whole mission can literally end in a highly explosive blink of an eye. Fortunately for the Euclid mission team, their gleaming new spacecraft left the Earth in one piece, and made its way to L2 to begin it's new job. It’s mission? Oh, just to solve five huge mysteries of the universe, from the nature of dark matter and dark energy, to unravelling the threads of the cosmic web.

Every so often, a Syzygy listener writes in with a cracking question that sends Emily and Chris off spelunking down the deep, deep sinkholes of astronomy and cosmology. This time, listener Eve asked an absolute cracker, to wit: Just how much energy is there in the universe right now? A simple question at first glance. At second glance (and every glance thereafter) it's not simple at all. We need to first consider, what is energy? What is the universe? And even, what is "now"? It's very...

Everyone's favourite bonkers red giant is back in the news again, and it has the supernova spotters in a froth. Last time we talked about Betelgeuse, it had gone unusually dim. Never fear, it's back with a vengeance — not just brighter, but pulsing twice as fast! Is the end nigh? Can we expect it to go boom soon? Well ... define 'soon'. Emily has all the answers.

Astronomers have spotted what seems to be a supermassive black hole devouring a huge gas cloud — and in the media it's being claimed as the Biggest Explosion in the History of Explosions. Except, is it though? And didn't we already talk about this, way back in Episode 61? And anyway, what does "biggest" even mean? Or "explosion", for that matter? Or "time"? It's all very confusing. Emily's here to make sense of it all.

Like many of us, as some stars get older, they get bigger. Like, really big. Big enough to swallow up any planets orbiting near by. Astronomers have known this for a while now, but they'd never actually seen it happen ... until now. Emily explains what's going on, what's been observed, why a planet-gobbling star seems the only real explanation, and what it all means for the Earth's distant future.

In 2023, the Moon is where it’s at — so many rockets taking so many little orbiters and landers and rovers and boxes full of weird trinkets ... just in the coming few months! And that’s before you even count the missions aimed at pushing human footprints into the lunar dust for the first time since the early 70s. Everyone and their dog is sending stuff to the moon, and Emily is here with all the details of six missions set to launch in the coming Northern Spring-Summer launch season.

The biggest black hole ever has been found — not supermassive, but *ultra*massive. Emily takes Chris on a tour of all the types of black hole, from the speculative minis, through the solar and intermediate mass kinds, to the stonking supermassive and frankly ludicrous ultramassive. And we ask, how exactly do you see a black hole when it's ... you know ... black?

In the hunt for life in the universe, astronomers are looking hard at the catalogue of potentially habitable exoplanets. The ones orbiting Red Dwarf stars seem promising — Red Dwarfs are really common, and we've just launched a shiny new space telescope that's perfect for observing them, their planets, and even their planets *atmospheres*. Trouble is, Red Dwarf stars are ... nasty. Like, really mean. Emily gives all the details on why we might not be discovering signs of life near a Red Dwarf...

"These six galaxies break cosmology!" scream the headlines. Yeah, nah — yeah, astronomers have found some galaxies in the JWST data that are crazy old, and yet seem to be just way too big. But nah: this doesn't mean cosmology is broken. As usual, the scientists ignore the click-baity headlines, roll their eyes and get on with figuring it all out. Plus, what time is it on the Moon? Not a simple question.

The Earth's core has been acting weird for at least 70 years now. We're not sure why, but sometimes it's spinning faster than the surface, sometimes slower. Emily explains how we know what's happening down in the core, which is impressive enough ... but then she shows how astronomers do the same for very distant stars, and Chris's head explodes. Plus, it's been a big week for aurora fans, and there's even some bonus Einteinian weirdness at the end.