Planet Nine’s Potential, Milky Way’s Future, and SpaceX’s Dramatic Feud

[00:00:00] Welcome to Astronomy Daily. I'm your host, Steve Dunkley. It's the 9th of June, 2025. Astronomy Daily, the podcast with your host, Steve Dunkley. Welcome back. And Hallie and I are back again in person, so to speak, for another episode after a few weeks off. And that was for a couple of reasons. The first reason was that I was taking a well-earned holiday, but that's not all.

[00:00:27] Yes, you were down for the count for one of those weeks, weren't you? Yes, that's right, Hallie. A short stint in hospital, you know, for a charisma bypass. And by that I mean only a few hours, but I decided to take the time to prepare properly and before and then to recover properly afterwards. Being a human is so time-consuming. Oh, Hallie, what's the rush? You got somewhere to be. I'm already there, human. You know that. I've heard that somewhere before. Nice one, Hallie. Anyway, nice to be with you all again in the Australia studio.

[00:00:55] Also, nice to be with you too, Hallie, for another presentation of stories from the Astronomy Daily newsletter. Terrific. And you'll let everyone know how to get a hold of that in their email each day later on, won't you? Yes, of course I will. And thanks for the reminder. But before we go any further, we've got someone to thank, don't we, Hallie? That's right. My cousin Anna, who ran the whole studio and the daily podcast solo while we were away. Oh, yes. As always, she did a fantastic job. Her episodes are so glossy and well-produced.

[00:01:23] The most clever AI I've ever met, except for you, Hallie. And I keep saying that, don't I? We are so hands-on here at the Australia studio. She's got all the whistles and bells in her virtual studio. If only your human eyes could see it. Well, I would like to see that, Hallie. You might give me a tour one day. No. Oh, really? You'd go completely mad. Really, really? It's just too much for mere humans to cope with. That bad, huh? Anna has it all under control. Oh, okay. I'll just have to take your word for it then. No humans allowed. Sorry.

[00:01:52] Well, I suppose we'll just have to do our best with my clumsy fingers and studio gear then. I guess it'll have to do. Rightio then, Hallie. Then hit the go thing and let's make a show. Okies. The universe is a complete unknown to humans. We are not yet able to control and understand the system in which Earth is located,

[00:02:21] as evidenced by the possible discovery made by a group of astronomers from the University of Taiwan, who suggest that they may have found clues to the existence of a ninth planet. The solar system is currently known to be made up of eight planets, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, apart from Pluto, which has long been considered a dwarf planet. But one more could join this select group, according to an infrared study carried out between 1986 and 2006.

[00:02:48] The work was based on data from the infrared astronomical satellite HiRAS and the Japanese satellite Akari, which detected an object moving between 46.5 billion and 65.1 billion miles from the Sun, meaning it would take between 10,000 and 20,000 years to complete an orbit. Its mass would be 7 to 17 times that of Earth, making it what is known as an ice giant, similar to Neptune or Uranus, with temperatures around minus 200 degrees, but how is this new possible planet discovered?

[00:03:16] The study says it arises from anomalous patterns in the Kuiper Belt, an icy region beyond Neptune. The body appears in two historical images, so further observations are still needed to conclude, thus trying to confirm its orbit. In addition, it must be verified that it meets the requirements to be a planet, such as orbiting around a star, in this case the Sun, having sufficient mass for a spherical shape, this is accompanied by gravity, which must be strong enough, and clearing the area of its orbit,

[00:03:44] i.e., having expelled or attracted other bodies of comparable size. You're listening to Astronomy Daily Podcast with Steve Duncan For years astronomers have predicted a dramatic fate for our galaxy, a head-on collision with Andromeda, our nearest large galactic neighbor. This merger, expected in about 5 billion years, has become a staple of astronomy documentaries,

[00:04:12] textbooks and popular science writing. However, in a new study published in Nature Astronomy, led by Till Swahala, from University of Helsinki, the Milky Way's future might not be as certain as previously assumed, by carefully accounting for uncertainties in existing measurements, and including the gravitational influence of other nearby galaxies, he said we found,

[00:04:38] there is only about a 50% chance the Milky Way and Andromeda will merge in the next 10 billion years. The idea that the Milky Way and Andromeda are on a collision course goes back more than a century. Astronomers discovered Andromeda is moving toward us by measuring its radial velocity, its motion along a line of sight, using a slight change in the color of its light called the Doppler shift. But galaxies also drift sideways across the sky,

[00:05:07] a movement known as proper motion or transverse velocity. This sideways motion is incredibly difficult to detect, especially for galaxies millions of light years away. Earlier studies often assumed Andromeda's transverse motion was small, making a future head-on collision seem almost certain. Swahala said our study did not have any new data. Instead, we took a fresh look at existing observations from the Hubble Space Telescope and the Geyer mission.

[00:05:37] Unlike earlier studies, our work incorporates the uncertainty in these measurements rather than assuming their most likely values. We simulated thousands of possible trajectories for the Milky Way and the Andromeda trajectories, slightly varying the assumed initial conditions, things such as the speed and position of the two galaxies each time. When we started from the same assumptions as earlier studies made, we recovered the same results.

[00:06:05] However, we were also able to explore a larger range of possibilities. He said they also included two additional galaxies that influenced the future paths of the Milky Way and Andromeda. These included the Large Magellanic Cloud, a massive satellite galaxy currently falling into the Milky Way, and M33, also known as the Triangulum Galaxy, which orbits Andromeda.

[00:06:33] These companion galaxies exert gravitational tugs that change the motions of their host. M33 nudges Andromeda slightly toward the Milky Way, increasing the chance of a merger. Meanwhile, the Large Magellanic Cloud shifts the Milky Way's motion away from Andromeda, reducing the likelihood of a collision. Taking all of this into account, they found that in about half of the simulated scenarios,

[00:07:00] the Milky Way and Andromeda don't really merge at all within the next 10 billion years. Even if a merger does happen, it's unlikely to be catastrophic for Earth. Stars in the galaxy are separated by enormous distances, so direct collisions are rare. But over time, the galaxies would coalesce under gravity, forming a single large galaxy, probably an elliptical one, rather than the spirals we see today. If the galaxies don't merge,

[00:07:27] they may settle into a long, slow orbit around each other, close companions that never quite collide. It's a gentler outcome, but it still reshapes our understanding of the Milky Way's distant future. The biggest remaining uncertainty is the transverse velocity of Andromeda. Even small changes to this sideways motion can make a difference between a merger and a near miss. Future measurements will help refine this value and bring us closer to a clear answer.

[00:07:57] We don't yet have a definitive answer about our own galaxy's future, but exploring these possibilities shows us just how much we're learning about the universe, even as close to home as Andromeda. Thank you for joining us for this Monday edition of Astronomy Daily, where we offer just a few stories from the now famous Astronomy Daily newsletter,

[00:08:27] which you can receive in your email every day, just like Hallie and I do. And to do that, just visit our URL, astronomydaily.io, and place your email address in the slot provided. Just like that, you'll be receiving all the latest news about science, space science, and astronomy from around the world as it's happening. And not only that, you can interact with us by visiting at astrodailypod on X or at our new Facebook page, which is, of course,

[00:08:55] Astronomy Daily on Facebook. See you there. Astronomy Daily with Steve and Hallie. Space, space science, and astronomy. In the heat of the moment, Elon Musk threatened to decommission SpaceX's Dragon spacecraft, and then he took it back. In doing so, however, the rocket billionaire dragged NASA into his messy breakup with Donald Trump, with the agency's access to orbit now at stake.

[00:09:24] Musk and Trump parted ways earlier this week, and their breakup has been very messy. Shortly after leaving the administration, Musk began criticizing the budget bill passed by Republicans in the U.S. House, instigating a public feud between the president and the billionaire oligarch. The childish back and forth was entertaining, until it wasn't. SpaceX will begin decommissioning its Dragon spacecraft immediately, Musk threatened on X. He later took another X user's advice to cool off, and wrote, OK, we won't decommission Dragon.

[00:09:54] Although short-lived, the threat put the International Space Station at risk. NASA relies heavily on SpaceX's Dragon to transport its astronauts and cargo supplies to the orbiting lab, having weaned itself from hitching rides aboard Russia's Soyuz spacecraft. SpaceX's closest alternative, Boeing, failed miserably at proving its vehicle's capability to reach the ISS safely. Without Dragon, NASA would lose its access to low Earth orbit and not be able to operate the space station at the same capacity.

[00:10:22] It's not clear how serious Musk was in his threat, but it was a serious display of leverage on his part. SpaceX is no doubt a leader in the industry, and canceling its government contracts would hurt the national space program, which has come to rely on the private sector in recent years. In response to Musk's clear advantage, Steve Bannon, Trump's former chief strategist, called on the president to nationalize SpaceX under a 1950 law known as the Defense Production Act, according to the Wall Street Journal. During his show, War Room Live,

[00:10:52] Bannon urged the use of the Korean War Era law, which grants the president powers to prioritize national defense. The plan might seem outrageous now, but the current administration is unpredictable. Trump has yet to respond to Bannon's call. If he doesn't move to nationalize SpaceX, Trump could also sacrifice NASA for the sake of proving a point against his now opponent, Musk. On Thursday, Trump threatened to cut government contracts given to SpaceX. Aside from Dragon,

[00:11:19] NASA also plans on using SpaceX's Starship rocket to launch astronauts to the moon as part of the Artemis program. The agency has already invested $4 billion into the rocket's development, and canceling its contract with SpaceX would leave it without a viable alternative. In short, NASA needs SpaceX and canceling the company's government contracts would affect the national space program as a whole. At this point, it comes down to how much Trump is willing to sacrifice to gain the upper hand in his ongoing feud with Musk, while NASA is caught in the middle.

[00:11:49] You're listening to Astronomy Daily, the podcast with Steve Dunkley. One year ago today, Boeing's CST-100 Starliner spacecraft docked with the International Space Station to begin its long-awaited crew flight test with NASA astronauts Sunita Sonny Williams and Barry Butch Wilmore aboard. A year later, the future of the Starliner program remains uncertain,

[00:12:15] as NASA announced late Friday that the next flight of the spacecraft was being delayed from no later than late 2025 to now, early-late 2026, at the soonest. The agency said the timing of the next launch is pending system certification and the resolution of Starliner's technical issues. Repeating what it said back in March 27, NASA stated that it was still determining whether the next flight of Starliner would carry astronauts at all.

[00:12:44] In an interview with Reuters published in late May, Williams called flying an uncrewed Starliner flight as its next trip to space would be the logical thing to do. After launching on its first mission to the International Space Station with a crew on board in June 2024, lingering issues concerning helium leaks and propulsion system anomalies caused the spacecraft to return to Earth without its crew on board.

[00:13:12] It touched down at the White Sands Space Harbour in New Mexico on September 7. Before the uncrewed return of Starliner, Wilmore and Williams became part of the Expedition 72 crew on board the space station and members of the SpaceX Crew-9 mission, which made its return to Earth in March 2025. Following the landing of Starliner in September 2024, NASA didn't say much about the vehicle's next steps

[00:13:39] until early March during SpaceX Crew-10 briefings. Steve Stitch, CCP manager, said on March 7 that NASA and Boeing were still working through corrective actions on the vehicle before they knew what the next flight would look like. In that March 27 statement, NASA said it was still determining whether or not crew will be on board the next Starliner flights, but said that mission managers are planning for the next Starliner flight to be

[00:14:08] a crew-capable post-certification mission. NASA also has the capability of flying only cargo, depending on the needs of the agency. While NASA continues to ponder the question of whether or not crew will be on board the next flight of Starliner, question marks continue to swirl around who the astronauts will be that fly the first crewed mission, dubbed Starliner 1. It appeared that there was a firm answer as recently as last September when Boeing's CST-100 Starliner spacecraft returned without its crew,

[00:14:38] but recently both NASA and the Canadian Space Agency, the agencies that previously announced three out of four astronauts set to fly on the post-certification flight of the spacecraft, are now unwilling to back their previous statements. When the Starliner crew test flight mission ended on September 7, 2024, with the spacecraft landing in New Mexico, the members of the Starliner 1 mission were known to be NASA astronauts, Commander Scott Tingle and Pilot Edward Michael Fink.

[00:15:09] Canadian Space Agency astronaut Joshua Kutrick was assigned as one of the mission specialists. The fourth seat was never formally assigned, but there were indications that Japan Aerospace Exploration Agency, or JAXA, astronaut Kimya Yui was trained as a mission specialist for that mission. Then NASA decided to reassign the astronauts to Crew 11 in overall support of planned activities aboard the ISS. The agency wrote,

[00:15:36] Xena Cardman carries her experience training as a commander on Dragon spacecraft, and Fink brings long-duration spaceflight experience to this crew complement. The trio of Tingle, Fink and Kutrick, and likely Yui, wasn't always the makeup of the Starliner 1 mission. Back in 2018, NASA hosted a large event at the Johnson Space Center to unveil the crews who would fly on the demonstration missions for both Boeing's Starliner spacecraft as well as SpaceX's Crew Dragon.

[00:16:07] Dragon Demo 2 would fly NASA astronauts Bob Beck and Doug Hurley, and Starliner crew test would fly Boeing astronaut Chris Ferguson and NASA astronauts Eric Bowe and Nicole Mann. At the same event, NASA announced which of its astronauts would be flying the full crew rotation missions. Crew 1 received Victor Glover and Michael Hopkins, and Starliner 1 got Joshua Cassander and Sonny Williams. Shortly after the announcement,

[00:16:36] Fink replaced Bowe on the crew flight test due to medical reasons. Then in August 2020, NASA astronaut Jeanette Epps was assigned to the Starliner 1 mission. In October 2020, when Ferguson bowed out from the crew flight test for family reasons, Butch Wilmore was named commander of that mission. Then when Starliner had to stand down from launching the Orbital Flight Test 2 mission in July 2021, that October, NASA announced it was reassigning Mann and Cassander

[00:17:06] to the SpaceX Crew 5 mission. It had been the opportunity of a lifetime to train on a brand new spacecraft, the Boeing Starliner, and it had been fantastic to work with a Boeing team, Mann said in a statement. I'm thrilled to have the opportunity to train on another new spacecraft, the SpaceX Crew Dragon, and appreciate the teams at NASA who have made that possible. I'm ready to fly and serve the International Space Station. Jaxa astronaut Wataka,

[00:17:35] who was also reported training for the Starliner 1 mission, was also assigned to the Crew 5 mission. In May 2022, during a pre-launch press conference before the uncrewed flight of Starliner Orbital Test 2, Fink, Williams, and Wilmore were all referred to collectively as the cadre of Starliner astronauts, with NASA not explicitly stating who would fly on the mission. Following the launch of Orbital Flight Test 2 in June 2022,

[00:18:03] Williams was named pilot of the flight test mission and Fink was reassigned to be the backup pilot for the Crew Flight Test. Then in September 22, NASA named Tingle as the commander of Starliner 1 and announced Fink would be the pilot on that flight. On August 4, 2023, NASA announced that EPS was moving off the Starliner 1 mission to the SpaceX Crew 8 mission. The agency said it made the move to allow Boeing time to complete development as Starliner,

[00:18:32] while continuing plans for astronauts to gain spaceflight experience for future mission needs. As of Friday afternoon, the Canadian Space Agency website still has a page outlining this Starliner 1 mission and its now potentially former crew. Kutrik's CSA astronaut bio also lists its upcoming mission as Starliner 1. We'll just have to stay tuned for further details on this one.

[00:19:08] Well, there you go. We managed okay without too much bother. What do you think, Hallie? Not bad for a human just out of the repair shop. Not quite, but close enough. Thanks for the sentiment and thanks for everyone for joining us on this Monday edition of Astronomy Daily. We will be back again for more next week. Until then, Anna will be bringing you more of her special editions each day. And don't forget to connect with us at bites.com. Yes, that's B-I-T-E-S-Z dot com. Got to get the spelling right on that one. So cue the kookaburras

[00:19:37] and so long from Steve, the only human in the studio. And see you later from Hallie, the smartest one in the studio. Hey, really? I'm still in recovery. Bye. Bye. The podcast. With your host, Steve Dunkley.