Ireland Joins the Artemis Coalition, Nuclear Mars Mission Advances & Halley's Meteor Peak

0:00 Anna: Hello and welcome to Astronomy Daily. I'm Anna. Avery: And I'm, um, avery. It's Monday, May 4, 2026. And yes, may the 4th be with you. Anna: But while you're looking up for X wings and TIE fighters, keep your eyes peeled for something very real shooting across the skies tonight because Halley's Comet has left us a little gift. Avery: That's right, the Eta Equinarians meteor shower is peaking this week. And for our Southern Hemisphere listeners in Australia, New Zealand and beyond, it could be spectac.

0:32 Anna: We have that story and five more today, including Ireland joining the Global Space Coalition, the next moon rocket's backbone arriving at Kennedy, and a, uh, nuclear powered mission to Mars that sounds like science fiction, but is very much science fact. Avery: And we'll visit two rovers having very different days on the Red planet and meet a galaxy that turns out to be a first time visitor to our cosmic neighborhood. Let's get into it. Anna: We start today with a historic signing happening right now as we record Ireland is joining the Artemis accords, becoming the 65th nation to commit to responsible and peaceful space exploration.

1:11 Avery: The ceremony is taking place at NASA headquarters in Washington, D.C. today, Monday, May 4, hosted by NASA Administrator Jared Isaacman, alongside Ireland's Ambassador to the US Geraldine Byrne Nason and Minister for Enterprise Peter Burke. Anna: Now, for listeners who may be new to the show, the Artemis Accords are a set of principles established back in 2020 during the first Trump administration, and they've grown steadily since. They cover everything from peaceful exploration and transparency to protecting historically significant sites in space and ensuring scientific data is shared openly.

1:48 Avery: What's notable here is the pace at which nations are joining. Just two weeks ago, Latvia signed as a 62nd signatory. Then Morocco joined as the 64th last week, and now Ireland makes 65. That's three new nations in a fortnight. Anna: Ireland actually has a, uh, growing space sector. It's home to the European Space Agency's European Space Astronomy center operations and has been part of ESA for decades. Joining the Accords formalizes its commitment to the broader international framework for lunar and deep space activities.

2:22 Avery: With 65 nations now on board, the Artemis Accords represent the most extensive multilateral framework for space exploration ever assembled. And the list keeps growing. As NASA says all countries are welcome, whether or not they have their own space program. Anna: A lovely milestone to mark on May 4th of all days. Avery: Well, Ireland did pick a memorable date, dory2. Anna: And we are staying firmly in the Artemis universe. The ink is barely dry on the Artemis 2 mission. Reid Wiseman, Victor Glover, Christina Koch and Jeremy Hansen splashed down just three weeks ago, and NASA is already pressing ahead at pace.

3:00 Avery: The massive core stage of the Space Launch Systems rocket for Artemis 3 arrived at Kennedy Space center in Florida last week on April 27, completing a 900 mile journey by barge from NASA's Michaud Assembly Facility in New Orleans. Anna: And when we say massive, we mean it. The SLS core stage is 212ft tall. When fully assembled, it houses two propellant tanks that together hold over 733,000 gallons of super chilled liquid propellant to feed four RS25 engines. It's the heart of the most powerful rocket currently flying.

3:39 Avery: The core stage is now inside the vehicle assembly bab, the vab, where it will be mated to its engine section. And NASA has been running everything in parallel. Solid rocket booster segments have already arrived by rail from Utah. And the mobile launcher was returned to the VAB even before the barge docked. Anna: Now here's where Artemis 3 gets interesting. Because this mission is not going to the moon's surface, its job is to test the rendezvous and docking capabilities between the Orion spacecraft and the commercial landers, SpaceX's Starship and Blue Origin's blue moon in low Earth orbit.

4:16 Think Apollo 9, which did the same kind of dress rehearsal in 1969. Avery: That groundwork is critical because it's Artemis 4 that will actually put astronauts back on the lunar surface targeted for 2028. So Artemis 3, likely launching in late 2027, is the essential bridge. Anna: There's something exhilarating about seeing hardware arrive. It's real, it's tangible, it's happening. Artemis, as one NASA official put it last week, is full steam ahead. Avery: Story three, and we're venturing a little further out to Mars and the most audacious propulsion experiment in decades.

4:57 NASA is pressing ahead with plans to launch the world's first nuclear electric powered interplanetary spacecraft in December 2028. Anna: It's called Space Reactor One Freedom SR One Freedom for short. And if it launches on schedule, it will be the first spacecraft to use nuclear fission for propulsion since the 1960s. Over 60 years in the making, the Avery: concept is called Nuclear Electric propulsion, or nep. Unlike nuclear thermal propulsion, which heats propellant directly, NEP uses a fission reactor to generate electricity, which then powers highly efficient ion thrusters.

5:38 The spacecraft accelerates slowly at first, but continuously building up extraordinary speed over weeks. Anna: The reactor itself will produce 20 kilowatts of electrical power using high assay low enriched uranium. And in a clever piece of engineering pragmatism, NASA is repurposing hardware that was already built for the now paused lunar gateway program, the power and propulsion element as the spacecraft bus. Avery: Once SR1 Freedom reaches Mars roughly a year after launch, it will deploy a payload called Skyfall three Ingenuity class helicopters that will scout the martian surface for subsurface water ice and survey potential future human landing sites.

6:23 Anna: Ingenuity, you'll recall, was only supposed to fly five times. On the Perseverance mission, it flew 72. So NASA knows these little rotorcraft can punch well above their weight. Avery: NASA Administrator Isaacman announced the mission back in March at what they called the ignition event, and he was emphatic this isn't a concept study. Hardware development is ramping up now with assembly and testing scheduled from early 2028. The December 2028 Mars launch window is the deadline, and the scope bends around it.

6:56 Anna: If successful, SR1 freedom does far more than test a propulsion system. It establishes the regulatory and launch precedents for nuclear hardware in space, activates the industrial base, and opens the door to megalot class reactors that could one day cut a human journey to Mars to just two months. The stakes couldn't be higher now for Avery: something you can actually go outside and experience yourself because the ADA Aquarids meteor shower is peaking right now with the best viewing on the mornings of May 5th and 6th.

7:31 Anna: And we know we've touched on this in recent episodes, but the peak is literally upon us. So here's your final briefing and viewing guide. Avery: The ETA Aquarids are one of the most famous annual meteor showers, and they come from a truly iconic source, the debris trail of Halley's Comet. Earth passes through Halley's dusty wake each May. Those particles, some as small as a grain of sand, slam into our atmosphere at around 66 km per second and vaporize in brilliant streaks of light. Anna: Halley's Comet last visited the inner solar system in 1986 and won't return until 2061.

8:09 So these annual showers are our way of staying connected to one of the most celebrated objects in astronomical history. Avery: Now, the great news for our Southern Hemisphere listeners, and that's a lot of you in Australia, New Zealand, and South Africa, is that this shower strongly favors your skies. The radiant point in Aquarius climbs much higher before dawn in the southern latitudes, giving you potential rates of around 50 meteors per hour under ideal dark sky conditions. Anna: The challenge this year is the moon.

8:43 On the peak night, we have a waning gibbous moon that's about 84% illuminated, which will wash out the fainter meteors. The best strategy is to find a dark location and physically block the moon behind a treeline, building or hill, your eyes will adjust and you'll catch the brighter, faster meteors. Avery: Even so, the pre dawn hours are, uh, the prime window. Watch from around 2am onwards as the radiant climbs highest. These are fast meteors that often leave glowing, persistent trails. Set up a reclining chair, wrap up warm, yes, even in autumn for you southern listeners and let the skies do the rest.

9:21 Anna: The shower remains active through May 28, so there are more opportunities ahead, even if clouds interrupt tonight. But the peak is now. Get out there. Avery: Story five takes us to the Red Planet, where two remarkable robots are currently writing history from opposite ends of geological time. NASA has released sweeping 360 degree panoramas from both Curiosity and Perseverance. And together they tell one of the most compelling stories in planetary science. Anna: Here's the beautiful paradox of what's happening.

9:55 Curiosity, now approaching 15 years on Mars, is climbing Mount Sharp and exploring progressively younger terrain. Perseverance, just five years in, is heading into some of the oldest landscapes in the entire solar system. They're time traveling in opposite directions. Avery: Curiosity's new panorama is assembled from over a thousand images captured between November and December last year. It reveals a vast network of what scientists call boxwork formations, low ridges that from orbit look like giant spiderwebs etched across the landscape.

10:30 These ridges formed billions of years ago when groundwater flowed through fractures in the bedrock, depositing minerals that hardened everything around them eroded away. What's left is essentially a fossil of ancient water activity. Anna: Perseverance is panorama focuses on a region near the rim of Jezero Crater, a place nicknamed Lac des Charmes. Assembled from nearly 980 images taken over several weeks in late 2025 and early 2026. The crater held a lake billions of years ago, fed by a river system.

11:05 The sediments that filled that lakebed could have preserved signs of microbial life. In 2024, Perseverance found a rock called Chayava Falls, covered with what scientists call leopard spots caused by chemical reactions that microbes are known to Earth. Avery: And Perseverance is carrying 23 intact rock cores in sealed tubes, waiting for a future sample return mission to bring them to Earth labs. The science locked inside those tubes could quite literally answer the question of whether life ever existed beyond our planet.

11:41 Anna: These panoramas aren't just beautiful, although they absolutely are. At over a billion pixels, curiosities alone is one of the largest it's ever taken. There's scientific archives, time capsules, two snapshots of a world that was once warm Wet and possibly alive. Avery: Two rovers, 3,775km apart, filling in the missing chapters of Mars's extraordinary biography. What a time to be alive. Anna: And our final story today is one for anyone who's looked south on a clear night and seen those two glowing smudges in the sky, the Large and Small Magellanic Clouds.

12:22 If you're in Australia or New Zealand, they're part of your night sky heritage. But new research suggests their history is far stranger than we ever imagined. Avery: The Large Magellanic Cloud, the LMC is our galaxy's most massive satellite. For decades, astronomers assumed it had been orbiting the Milky Way for billions of years, making multiple passes. A competing theory said it's actually on its first approach. Now a new preprint paper claims to provide what the authors call definitive evidence that the LMC is a first time visitor.

12:57 Anna: The paper comes from researchers including Scott Luccini and colleagues, and it addresses a fierce ongoing debate in astrophysics. The stakes are high because the LMC is genuinely massive. It's roughly one tenth to one fifth the mass of the Milky Way itself. A galaxy that big, swinging through our neighborhood sends gravitational shock waves through everything around us. Avery: The evidence lies in the LMC's corona, a, uh, diffuse halo of warm gas surrounding it. If the LMC had made a previous close pass by the Milky Way, that corona should have been stripped away by our galaxy's gravity.

13:32 The fact that it's still there, relatively intact, strongly supports the first infall scenario. It also explains why the Small Magellanic Cloud and other satellites, ah, that travel with the LMC haven't been tidally torn apart. They simply haven't had enough close encounters with the Milky Way to be disrupted. Anna: There's something almost poetic about this. That gorgeous smudge of light you can see from a southern dark sky visible to the naked eye, named after Magellan, is essentially a first time visitor.

14:02 It fell toward us for the first time in cosmic history, passed its closest point recently in astronomical terms, and now is swing back out. We're witnessing something that has never happened before in our galaxy's history. Avery: It also rewrites our understanding of the Magellanic Stream, that vast trail of hydrogen gas stretching across the southern sky behind the clouds. That stream was thought to have been shaped by multiple Milky Way interactions. Now researchers have to explain it through LMC SMC interactions alone.

14:34 More work ahead. But what a puzzle to have for Anna: our Southern Hemisphere listeners. Next time you step outside on a clear night and spot the Magellanic Clouds, take a moment. You're watching a, uh, first encounter between galaxies unfolding in slow motion across the cosmos. Avery: And that's your Astronomy daily for Monday, May 4. Six stories from Ireland joining the Space Coalition to a galaxy making its first visit in cosmic history. What a day to be an astronomy. Anna: Enthusiastic if you're heading out to watch the IDA Aquarids tonight or tomorrow morning, we'd love to hear how you got on.

15:09 Find us at astronomydaily IO or reach out on X, Instagram, TikTok, Facebook or Tumblr astrodaily pod. Avery: And if the show brings you joy, please leave us a review. Wherever you listen, it genuinely makes a difference and helps more people find us. Anna: This has been Astronomy Daily, part of the bytes.com podcast network. I'm Anna and just before I go, a quick reminder to check out our sponsor's M money saving, risk free deal. I'm talking about NordVPN and when you're ready to secure your online life, they're the ones to use.

15:41 We certainly do get all the details via the sponsor link in the show Avery: notes and I'm Avery. Keep looking up. The universe has never been more alive. We'll see you tomorrow.

15:55 Anna: Mhm.

16:03 The story.