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

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Anna: Hello and welcome to Astronomy Daily.

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I'm Anna.

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Avery: And I'm, um, avery. It's Monday, May 4,

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2026. And yes, may the 4th be with

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you.

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Anna: But while you're looking up for X wings and

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TIE fighters, keep your eyes peeled for

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something very real shooting across the skies

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tonight because Halley's Comet has left us

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a little gift.

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Avery: That's right, the Eta Equinarians meteor

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shower is peaking this week. And for our

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Southern Hemisphere listeners in Australia,

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New Zealand and beyond, it could be spectac.

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Anna: We have that story and five more today,

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including Ireland joining the Global Space

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Coalition, the next moon rocket's backbone

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arriving at Kennedy, and a, uh, nuclear

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powered mission to Mars that sounds like

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science fiction, but is very much science

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fact.

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Avery: And we'll visit two rovers having very

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different days on the Red planet and meet a

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galaxy that turns out to be a first time

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visitor to our cosmic neighborhood. Let's get

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into it.

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Anna: We start today with a historic signing

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happening right now as we record Ireland

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is joining the Artemis accords, becoming the

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65th nation to commit to responsible and

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peaceful space exploration.

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Avery: The ceremony is taking place at NASA

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headquarters in Washington, D.C. today,

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Monday, May 4, hosted by NASA

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Administrator Jared Isaacman, alongside

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Ireland's Ambassador to the US Geraldine

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Byrne Nason and Minister for Enterprise Peter

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Burke.

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Anna: Now, for listeners who may be new to the

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show, the Artemis Accords are a set of

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principles established back in 2020

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during the first Trump administration, and

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they've grown steadily since. They cover

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everything from peaceful exploration and

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transparency to protecting historically

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significant sites in space and ensuring

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scientific data is shared openly.

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Avery: What's notable here is the pace at which

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nations are joining. Just two weeks ago,

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Latvia signed as a 62nd signatory.

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Then Morocco joined as the 64th last week,

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and now Ireland makes 65. That's

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three new nations in a fortnight.

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Anna: Ireland actually has a, uh, growing space

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sector. It's home to the European Space

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Agency's European Space Astronomy center

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operations and has been part of ESA for

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decades. Joining the Accords formalizes

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its commitment to the broader international

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framework for lunar and deep space

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activities.

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Avery: With 65 nations now on board, the Artemis

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Accords represent the most extensive

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multilateral framework for space exploration

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ever assembled. And the list keeps growing.

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As NASA says all countries are welcome,

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whether or not they have their own space

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program.

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Anna: A lovely milestone to mark on May 4th of

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all days.

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Avery: Well, Ireland did pick a memorable date,

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dory2.

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Anna: And we are staying firmly in the Artemis

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universe. The ink is barely dry on the

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Artemis 2 mission. Reid Wiseman, Victor

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Glover, Christina Koch and Jeremy Hansen

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splashed down just three weeks ago, and

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NASA is already pressing ahead at pace.

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Avery: The massive core stage of the Space Launch

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Systems rocket for Artemis 3 arrived at

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Kennedy Space center in Florida last week on

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April 27, completing a 900 mile

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journey by barge from NASA's Michaud Assembly

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Facility in New Orleans.

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Anna: And when we say massive, we mean it.

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The SLS core stage is

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212ft tall. When fully

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assembled, it houses two propellant tanks

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that together hold over

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733,000 gallons

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of super chilled liquid propellant to feed

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four RS25 engines. It's the

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heart of the most powerful rocket currently

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flying.

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Avery: The core stage is now inside the vehicle

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assembly bab, the vab, where it will be mated

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to its engine section. And NASA has been

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running everything in parallel. Solid rocket

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booster segments have already arrived by rail

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from Utah. And the mobile launcher was

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returned to the VAB even before the barge

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docked.

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Anna: Now here's where Artemis 3 gets interesting.

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Because this mission is not going to the

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moon's surface, its job is to test the

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rendezvous and docking capabilities between

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the Orion spacecraft and the commercial

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landers, SpaceX's Starship and Blue

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Origin's blue moon in low Earth orbit.

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Think Apollo 9, which did the same kind of

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dress rehearsal in 1969.

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Avery: That groundwork is critical because it's

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Artemis 4 that will actually put astronauts

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back on the lunar surface targeted for

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2028. So Artemis 3,

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likely launching in late 2027, is

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the essential bridge.

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Anna: There's something exhilarating about seeing

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hardware arrive. It's real, it's

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tangible, it's happening. Artemis,

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as one NASA official put it last week, is

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full steam ahead.

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Avery: Story three, and we're venturing a little

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further out to Mars and the most audacious

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propulsion experiment in decades. NASA

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is pressing ahead with plans to launch the

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world's first nuclear electric powered

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interplanetary spacecraft in December

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2028.

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Anna: It's called Space Reactor One Freedom

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SR One Freedom for short. And if it

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launches on schedule, it will be the first

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spacecraft to use nuclear fission for

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propulsion since the 1960s.

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Over 60 years in the making,

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the

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Avery: concept is called Nuclear Electric

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propulsion, or nep.

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Unlike nuclear thermal propulsion, which

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heats propellant directly, NEP uses

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a fission reactor to generate electricity,

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which then powers highly efficient ion

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thrusters. The spacecraft accelerates slowly

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at first, but continuously building up

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extraordinary speed over weeks.

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Anna: The reactor itself will produce 20

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kilowatts of electrical power using high

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assay low enriched uranium. And in

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a clever piece of engineering pragmatism,

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NASA is repurposing hardware that was already

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built for the now paused lunar gateway

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program, the power and propulsion element

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as the spacecraft bus.

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Avery: Once SR1 Freedom reaches Mars roughly a

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year after launch, it will deploy a payload

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called Skyfall three Ingenuity class

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helicopters that will scout the martian

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surface for subsurface water ice and

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survey potential future human landing sites.

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Anna: Ingenuity, you'll recall, was only supposed

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to fly five times. On the Perseverance

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mission, it flew 72. So

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NASA knows these little rotorcraft can punch

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well above their weight.

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Avery: NASA Administrator Isaacman announced the

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mission back in March at what they called the

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ignition event, and he was emphatic this

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isn't a concept study. Hardware development

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is ramping up now with assembly and testing

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scheduled from early 2028. The December

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2028 Mars launch window is the deadline, and

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the scope bends around it.

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Anna: If successful, SR1 freedom does

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far more than test a propulsion system. It

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establishes the regulatory and launch

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precedents for nuclear hardware in space,

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activates the industrial base, and opens the

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door to megalot class reactors that could one

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day cut a human journey to Mars to just

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two months.

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The stakes couldn't be higher now for

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Avery: something you can actually go outside and

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experience yourself because the ADA

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Aquarids meteor shower is peaking right now

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with the best viewing on the mornings of May

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5th and 6th.

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Anna: And we know we've touched on this in recent

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episodes, but the peak is literally upon us.

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So here's your final briefing and viewing

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guide.

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Avery: The ETA Aquarids are one of the most famous

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annual meteor showers, and they come from a

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truly iconic source, the debris trail of

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Halley's Comet. Earth passes through

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Halley's dusty wake each May. Those

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particles, some as small as a grain of sand,

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slam into our atmosphere at around 66

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km per second and vaporize in

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brilliant streaks of light.

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Anna: Halley's Comet last visited the inner solar

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system in 1986 and won't return

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until 2061. So these annual

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showers are our way of staying connected to

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one of the most celebrated objects in

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astronomical history.

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Avery: Now, the great news for our Southern

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Hemisphere listeners, and that's a lot of you

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in Australia, New Zealand, and South Africa,

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is that this shower strongly favors your

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skies. The radiant point in Aquarius

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climbs much higher before dawn in the

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southern latitudes, giving you potential

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rates of around 50 meteors per hour under

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ideal dark sky conditions.

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Anna: The challenge this year is the moon. On the

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peak night, we have a waning gibbous moon

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that's about 84% illuminated, which will wash

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out the fainter meteors. The best strategy is

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to find a dark location and physically block

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the moon behind a treeline, building or hill,

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your eyes will adjust and you'll catch the

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brighter, faster meteors.

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Avery: Even so, the pre dawn hours are, uh, the

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prime window. Watch from around 2am

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onwards as the radiant climbs highest. These

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are fast meteors that often leave glowing,

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persistent trails. Set up a reclining

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chair, wrap up warm, yes, even in

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autumn for you southern listeners and let the

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skies do the rest.

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Anna: The shower remains active through May 28,

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so there are more opportunities ahead, even

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if clouds interrupt tonight. But the peak is

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now. Get out there.

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Avery: Story five takes us to the Red Planet, where

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two remarkable robots are currently writing

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history from opposite ends of geological

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time. NASA has released sweeping

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360 degree panoramas from both Curiosity

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and Perseverance. And together they tell

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one of the most compelling stories in

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planetary science.

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Anna: Here's the beautiful paradox of what's

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happening. Curiosity, now approaching 15

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years on Mars, is climbing Mount Sharp

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and exploring progressively younger terrain.

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Perseverance, just five years in, is heading

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into some of the oldest landscapes in the

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entire solar system. They're time traveling

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in opposite directions.

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Avery: Curiosity's new panorama is assembled from

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over a thousand images captured between

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November and December last year. It reveals

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a vast network of what scientists call

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boxwork formations, low ridges that

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from orbit look like giant spiderwebs etched

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across the landscape. These ridges formed

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billions of years ago when groundwater flowed

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through fractures in the bedrock, depositing

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minerals that hardened everything around them

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eroded away. What's left is essentially

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a fossil of ancient water activity.

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Anna: Perseverance is panorama focuses on a region

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near the rim of Jezero Crater, a place

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nicknamed Lac des Charmes. Assembled from

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nearly 980 images taken over

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several weeks in late 2025 and early

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2026. The crater held a lake

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billions of years ago, fed by a river system.

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The sediments that filled that lakebed could

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have preserved signs of microbial life. In

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2024, Perseverance found a rock called

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Chayava Falls, covered with what scientists

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call leopard spots caused by chemical

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reactions that microbes are known to

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Earth.

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Avery: And Perseverance is carrying 23

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intact rock cores in sealed tubes,

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waiting for a future sample return mission to

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bring them to Earth labs. The science

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locked inside those tubes could quite

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literally answer the question of whether life

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ever existed beyond our planet.

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Anna: These panoramas aren't just beautiful,

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although they absolutely are. At over a

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billion pixels, curiosities alone is one

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of the largest it's ever taken. There's

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scientific archives, time capsules,

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two snapshots of a world that was once warm

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Wet and possibly alive.

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Avery: Two rovers,

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3,775km

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apart, filling in the missing chapters of

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Mars's extraordinary biography.

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What a time to be alive.

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Anna: And our final story today is one for anyone

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who's looked south on a clear night and seen

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those two glowing smudges in the sky, the

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Large and Small Magellanic Clouds. If you're

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in Australia or New Zealand, they're part of

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your night sky heritage. But new research

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suggests their history is far stranger than

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we ever imagined.

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Avery: The Large Magellanic Cloud, the LMC

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is our galaxy's most massive satellite.

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For decades, astronomers assumed it had been

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orbiting the Milky Way for billions of years,

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making multiple passes. A competing theory

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said it's actually on its first approach.

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Now a new preprint paper claims to provide

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what the authors call definitive evidence

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that the LMC is a first time visitor.

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Anna: The paper comes from researchers including

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Scott Luccini and colleagues, and it

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addresses a fierce ongoing debate in

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astrophysics. The stakes are high because the

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LMC is genuinely massive. It's roughly

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one tenth to one fifth the mass of the Milky

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Way itself. A galaxy that big, swinging

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through our neighborhood sends gravitational

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shock waves through everything around us.

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Avery: The evidence lies in the LMC's corona, a, uh,

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diffuse halo of warm gas surrounding it. If

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the LMC had made a previous close pass by the

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Milky Way, that corona should have been

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stripped away by our galaxy's gravity. The

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fact that it's still there, relatively

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intact, strongly supports the first infall

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scenario. It also explains why the Small

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Magellanic Cloud and other satellites, ah,

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that travel with the LMC haven't been tidally

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torn apart. They simply haven't had enough

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close encounters with the Milky Way to be

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disrupted.

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Anna: There's something almost poetic about this.

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That gorgeous smudge of light you can see

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from a southern dark sky visible to the naked

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eye, named after Magellan, is essentially a

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first time visitor. It fell toward us for the

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first time in cosmic history, passed its

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closest point recently in astronomical terms,

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and now is swing back out. We're

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witnessing something that has never happened

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before in our galaxy's history.

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Avery: It also rewrites our understanding of the

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Magellanic Stream, that vast trail of

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hydrogen gas stretching across the southern

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sky behind the clouds. That stream was

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thought to have been shaped by multiple Milky

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Way interactions. Now researchers have to

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explain it through LMC SMC interactions

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alone. More work ahead. But what a puzzle to

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have for

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Anna: our Southern Hemisphere listeners. Next time

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you step outside on a clear night and spot

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the Magellanic Clouds, take a moment. You're

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watching a, uh, first encounter between

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galaxies unfolding in slow motion

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across the cosmos.

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Avery: And that's your Astronomy daily for Monday,

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May 4. Six stories from Ireland

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joining the Space Coalition to a galaxy

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making its first visit in cosmic history.

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What a day to be an astronomy.

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Anna: Enthusiastic if you're heading out to watch

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the IDA Aquarids tonight or tomorrow morning,

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we'd love to hear how you got on. Find us at

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astronomydaily IO or reach out on

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X, Instagram, TikTok, Facebook or

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Tumblr astrodaily pod.

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Avery: And if the show brings you joy, please leave

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us a review. Wherever you listen, it

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00:15:21.830 --> 00:15:23.790
genuinely makes a difference and helps more

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people find us.

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Anna: This has been Astronomy Daily, part of the

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bytes.com podcast network. I'm Anna

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and just before I go, a quick reminder to

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check out our sponsor's M money saving, risk

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free deal. I'm talking about NordVPN

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and when you're ready to secure your online

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life, they're the ones to use. We certainly

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do get all the details via the sponsor link

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in the show

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Avery: notes and I'm Avery. Keep looking up.

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The universe has never been more alive.

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We'll see you tomorrow.

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Anna: Mhm.

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The story.