Moon Robots, a Cosmic Slowdown Debate, and NASA's Newest Astronaut

One-liner: Short Wave host Regina Barber's biweekly space-news roundup with All Things Considered host Scott Detrow and producer Berly McCoy, covering three stories: a new Science Robotics study on how Japan's half-pound "transforming" moon robots actually performed; a nearly 30-year-old fight over whether the universe's expansion is speeding up or slowing down, reignited by a Yonsei University team's slowdown claim and a new rebuttal paper; and newly selected Artemis III astronaut Andre Douglas on the Iceland training that's preparing him for a future moon landing.

Moon-Bound "Transformers": Half-Pound Scouts for Bigger Rovers

Key findings: A pair of baseball-sized, roughly half-pound spherical robots rode along on Japan's first successful moon landing (the source doesn't name the specific mission or robot model, and says only that the landing happened "a couple of years ago"). On touchdown, each half of the sphere splits open into a spinning wheel with a camera revealed in the center, letting the robots waddle across rough terrain and navigate entirely on their own. A new study published recently (described as "last week" relative to taping) in Science Robotics reviewed how they actually performed on the lunar surface: rather than run deep science instruments, they scout ahead — snapping pictures of the surface and the lander and covering terrain bigger rovers can't reach. Planetary scientist Roger Weems, who wasn't involved in the program, called redundancy their biggest edge: "These are not expensive devices. You can have several of them. And if one or two fails, then you still have others." The moon's gravity is one-sixth of Earth's, which is why the robots visibly bounce as they move — a low-gravity design Weems suggested could extend to asteroids and even Mars.

Is the Universe's Expansion Speeding Up or Slowing Down? A Decades-Old Fight Reignites

Key findings: Almost 30 years ago, astronomers discovered that the universe isn't just expanding — that expansion is accelerating. In the last few years, though, a group of scientists upended that picture by claiming the expansion is actually slowing down. A paper out last week in Monthly Notices of the Royal Astronomical Society pushes back, arguing the old accelerating-universe framework still holds — and the debate continues. The slowdown camp, a team at Yonsei University in South Korea, has already posted a rebuttal, standing by their central claim: the standard method for measuring cosmic expansion is fundamentally flawed. That method involves measuring the brightness of supernovas — a type of exploding star — and correcting for factors like how long the explosion lasts and how much dust sits in the way. The Yonsei team argues those corrections have always left out the age of a supernova's host galaxy; once that's factored in, they say, the answer flips to a slowing expansion — a finding that would be huge if true. Most astronomers the show spoke to remain skeptical of the slowdown claim: the supernova method has been fine-tuned for almost 30 years, and other independent methods still point to acceleration. Yale astrophysicist Priyamvada Natarajan, who wasn't involved in the work, is skeptical too, but frames the back-and-forth as science working as intended: "Scientists by nature are skeptical. And even for an idea that has been validated and accepted, if there is a new argument, we do take it seriously and we interrogate it." The stakes: if the universe keeps accelerating, everything eventually drifts apart into a cold death; if it's really slowing, it could instead collapse back in on itself — what astronomers call the Big Crunch.

Artemis III's New Crew Trains for the Moon — in Iceland and Beyond

Key findings: The crew for Artemis III has just been announced [the source describes Artemis III as "the mission that will do lots of maneuvers in space in low Earth orbit" — commonly that profile is associated with Artemis II rather than Artemis III; recorded here as stated, without outside correction]. Host Scott Detrow interviewed newly selected astronaut Andre Douglas the day his selection was announced. Douglas served on the backup crew for Artemis II and trained alongside them, including a trip to Iceland: "We did a 24-mile hike in two days in Iceland, just to go through a hard challenge of land navigation, as if we're learning how to be really good operators." Training sites are chosen as geological analogs for the moon — Iceland's rocky terrain and rock composition closely resemble lunar conditions, and Apollo-era astronauts trained there too, calling it the closest thing to the moon's surface they'd seen; two NASA astronauts are headed back to Iceland this July for more training. The prep isn't just for lunar missions: astronaut hopefuls have also trekked the lava beds of Hawaii Volcanoes National Park under heavy packs, doing geological fieldwork while dealing with deliberately limited, delayed communications meant to simulate a Mars mission's comms lag. And a simulated Mars mission is underway right now at NASA's Johnson Space Center in Houston, where four researchers have been living inside a 3D-printed habitat since last October, running experiments as if they were on Mars, for a stay of just over a year.

Rich Details & Trivia

• Barber opens with a "Transformers on the moon" tease, then immediately deflates it: "It's not about Optimus Prime. They're very different." The trio compares Transformers-movie credentials — Detrow's seen them, McCoy's seen "some" but finds them "kind of forgettable" ("no hate mail, please"), and Barber has seen none.
• McCoy compares the robots' waddling gait to her toddler — "always exploring, always expanding" — and rides that line straight into the expanding-universe segment, which Detrow calls "a really smooth transition."
• On the universe's ultimate fate, Barber stakes her claim: "I'm team cold death." (She's also squarely in the accelerating-expansion majority on the earlier debate: "Right. Like me.")
• The episode closes with the trio joking about a "Spacing Out" field trip to Iceland to chase the Northern Lights, and ends on a runner about the universe's fate: Detrow jokes he's "floating away," McCoy asks "accelerating or decelerating," and Barber answers "decelerating — he stopped."

Cross-Domain Connections

All three stories here — a government moon-robot engineering report, an academic cosmology dispute, and a NASA astronaut-training feature — stay entirely within government science and academic publishing. No commercial space companies, suppliers, or chipmakers come up. The acquired domain already has pages on NVIDIA, TSMC, and Lockheed Martin, but their subject matter (chip industry history, defense-contractor business history) doesn't meaningfully overlap with any of this episode's three stories, so no genuine cross-domain link applies here.

Pages to Build

• lunar-gravity — the moon's roughly one-sixth-Earth gravity underlies both the robots' bouncing gait and the logic behind choosing geological analog sites like Iceland; likely to recur across future space episodes.
• universe-expansion-debate — the accelerating-vs-slowing fight over cosmic expansion, an almost-30-year-old dispute this episode is only the latest round of; worth tracking as a standalone concept across episodes.
• andre-douglas — newly selected Artemis III astronaut and a central figure in NASA's crewed lunar program, likely to resurface in future Artemis-related episodes.

Source · shortwave