Artemis II: Homeward Bound and The Lost Mars Mission

Hello, and welcome to Astronomy Daily. I'm Anna and I'm Avery. It is Wednesday, April eighth, twenty twenty six, and what a week it has been. We are deep into what might be the most extraordinary few days in human spaceflight since nineteen seventy two. Artemis two is heading home, and we are going to walk you through exactly where the crew is right now, what happened on flight day seven, and what to expect as they come screaming back through the atmosphere on Friday. Screaming is right. We are talking twenty five thousand miles per hour, the fastest crude re entry in history. But more on that in a moment. We have also got a cargo launch delay that has created one of the most beautifully poetic scheduling coincidences we have ever seen in spaceflight. Some planet shaking new science about how Earth actually formed, fresh data from an alien comet courtesy of a spacecraft designed for Jupiter's mood uns. A new comic for skywatchers to get excited about after last week's spectacular disappointment, and then. To close the show today, something a little different, A mystery, a space mystery that is thirty years old and has never been solved. I have been looking forward to this one all day. I won't lie. Doh of I let's get into it. This is Astronomy Daily, season five, episode eighty four. Right, so let's set the scene. Artemis two launched on April first, Yes, April Fool's Day, and no it was not a joke. And the crew of four have already done the most extraordinary thing. On Monday, Flight Day six, they flew around the far side of the Moon. They set a new record for the furthest humans have ever been two hundred and fifty two thousand, seven hundred and fifty six miles. Nobody in human history has ever been that far. And Flight Day seven, which was yesterday Tuesday, was the day after all drama, the science debrief day, the comedown day, well sort of. They woke up to Tokyo drifting by glass animals and Denzel Curry and I genuinely love whoever selects these wake up songs is having an absolute blast. The playlist creation on Artemis two has been exceptional. Somebody at NASA is doing their best work. They woke up thirty six thousand miles from the moon, two hundred thirty six thousand miles from Earth, and the big item on the agenda was a fifteen minute audio call ship to ship with the crew aboard the International Space Station. So you have four astronauts who have just been further from Earth than any human in over fifty years calling up the International Space Station, which from where O'Ryan was sitting must have felt practically next. Door, right relatively speaking. They spoke with NASA astronauts Jessica Mere, Jack Hathaway, Chris Williams, and ESA's Sophie Adenaut. Just imagine that conversation. So, how was the Moon, you know, bit far? And after that the science debrief. The Artemis two lunar science team had a full debrief session with the crew to capture everything they observed during the flyby while the memories were still sharp. Which makes complete sense, right, These four people have just seen parts of the Moon no human eye has ever seen directly, the far side, craters like Vavlov and the Oriental Basin, an ancient lava field on the border of the Moon's near and far side that's almost impossible to see from Earth. You want those impressions captured immediately. And then in the evening at about nine pm Eastern, Orion fired the first of three trajectory correction burns to begin fine tuning the return path to Earth. Though we are officially in the home stretch. And Flight day eight, which is today, the crew has two key tasks. First, a radiation shelter construction demonstration. Which sounds alarming but is actually a plan drill. The practice assembling a makeshift radiation shelter inside Orion using available materials in case of a solar event during a deep space mission, exactly the kind of emergency preparedness you need locked in before Artemis three heads to the lunar surface. And second manual piloting tests. The crew gets to hand fly Orion directly, which, given that computers handled basically everything on this mission, must feel a bit like being handed the wheel. And then, Friday, April tenth, splash down. Flight day ten, Orion re enters the atmosphere at twenty five thousand miles per hour. That is the fastest crude re entry ever attempted. The heat shields, which caused so much concern and engineering work before this mission, will be put to its ultimate. Test, and collecting data from that re entry is actually one of the core mission objectives, so NASA will be watching those heat shield readings very closely. Blashdown is scheduled for about eight pm Eastern off the coast of San Diego. The USS John P. Murtha, a Navy amphibious transport docship, will be waiting. The crew will be recovered by helicopter, taking a board for medical evaluation, then flown back to Houston, and. That will be it the first time humans have returned from beyond Earth orbit since Apollo seventeen in nineteen seventy two. Mission complete, but. Right now Reid Wiseman, Victor Glover, Christina Koch, and Jeremy Hansen are heading home and we could not be more excited for them. All right, from the crew heading back to Earth to a cargo ship heading up to the space station with a slight detour through the weather forecast. Yes So, as we reported yesterday, Northrop Grumman's Signus CRS twenty four mission was supposed to launch today Wednesday morning from Cape Canaveral on SpaceX Falcon nine, carrying about eleven thousand pounds of cargo to the International Space Station, but. The weather at Space Launch Complex forty had other ideas and teams have pushed the launch to Friday, April tenth, targeting eight oh three in the morning Eastern backup opportunity on Saturday the eleventh if needed. Now here's why this matters beyond just a weather delay. Friday April tenth is also the day Artemis two splashdowns, so. On the same day, four astronauts returned from the Moon, the furthest humans have been from Earth in over fifty years. A fresh cargo ship launches towards the space station simultaneously. Cape Canaveral is going to be having quite a Friday. The spacecraft itself is the Signus Excel, the larger configuration carrying about eleven thousand pounds of pressurized cargo. Northrop Grumman has named this one the SS Stephen R. Nagel, in honor of the NASA astronaut who flew four Shuttle missions and longed over seven hundred and twenty hours in space. Beautiful tradition. Naming these cargo ships and the science aboard CRS twenty four is genuinely interesting. There's a new module for the Cold Atom Lab on the station, NASA's quantum Science facility to help investigate dark matter and potentially improve computing technology. There's also hardware to produce greater numbers of therapeutic stem cells for blood diseases and cancer, model organisms for a gut microbiome study, and a receiver to improve space weather models that protect GPS and radar infrastructure. Though it's not just food and equipment, this is a proper science delivery. Once it arrives, Signus doesn't dock automatically the way Dragon does. Astronauts Chris Williams and Jack Hathaway will use the Canid Arm two robotic arm to grab it and bring it in. They've been practicing. There was a report last week of them running simulations together in the cupola. And Signus is scheduled to stay at the station until October before undocking with several thousand pounds of trash and burning up on re entry. A rather unglamorous end, but a useful one. Weather permitting. Friday should be quite the day. Okay. Story three, and this one is a genuine rewrite of something we thought we understood. Where did Earth come from? We know the broad answer. Four and a half billion years ago, a cloud of gas and dust collapsed, the Sun formed, and the leftover material clumped into planets, but where exactly did the specific material that became Earth come from. For decades, the accepted model was that Earth got a significant chunk of its building material from the outer Solar System from beyond Jupiter. Estimates ranged from six percent to as much as forty percent of Earth's mass, and the reason this mattered is water pliantists needed that outer Solar System contribution to explain where Earth's oceans came from, because the Inner Solar System was thought to be too dry. But a new study from Eth Zurich, published in the journal Nature Astronomy, has just turned that on its head. Planetary scientists Paulososi and Dan Bauer analyze isotopic ratios of meteorites from across the Solar System and compare them to Earth's composition. Their conclusion, Earth formed almost entirely from Inner Solar System material, the outer Solar System contribution less than two percent, and possibly nothing at all. Now, isotopes are essentially atomic fingerprints. Different regions of the Solar System produce slightly different ratios of the same elements, and you can use those signatures to trace where material originated. Previous studies mostly looked at one or two isotopic systems. Saucy and Bauer looked at ten. Ten different isotopic systems analyzed with statistical methods rarely used in geochemistry, and when you look at all ten together, the picture is unambiguous. Earth is built of non carbonaceous material. Inner Solar System stuff through went through. Which immediately raises an enormous question. If Earth didn't get its water from the outer Solar System from comets and water rich asteroids drifting inward, where did the water come from? And the answer, according to this study is it was already here. Water and volatile elements must have been present in the Inner Solar System from the very beginning. We just didn't realize it. And why was so little Outer Solar System material reaching Earth in the first place? Jupiter. Jupiter formed extremely quickly and grew enormous, and its gravity carved gap in the young protoplanetary disc, essentially a barrier between the inner and outer Solar System. This study suggests that barrier was almost completely impermeable. Almost nothing got through. Jupiter, the bouncer of the Solar system. Sorry, outer Solar system material not tonight. One of the researchers, Dan Bauer, said, we were truly astonished to find that Earth is composed entirely from Inner Solar System material, distinct from any combination of existing meteorites. Even they didn't expect this result. The implications are genuinely big. If water was already present in the Inner Solar System, that changes how we think about the conditions that made life possible here, and it has implications for other planetary systems. Rocky planets around Sun like stars might be wetter than we assumed. It's the kind of result that makes you look at the ground beneath your feet differently. This material formed locally billions of years ago without much help from the wider Solar System. Jupiter kept the neighborhood tidy. And Earth's water was here from the starts, which is kind of beautiful. Actually digging with space science, and this one involves an alien comet, a spacecraft on its way to Jupiter's moons, and an instrument that was never designed to do what it ended up doing. We have followed three iatls closely on the show Quick Catchup. Three IATLS is an interstellar comment, only the third object ever confirmed to have entered our Solar System from interstellar space. Discovered in July twenty twenty five, reached its closest approach to the Sun on October twenty ninth. And when I say it was moving fast two hundred and fifty thousand kilometers per hour, nothing that forms in our solar system moves like that. It is genuinely a visitor from another star system. We have no idea which one. In November twenty twenty five, isa's Juice spacecraft, the Jupiter icy Moons Explorer, currently en route to Jupiter, was in a fortunate position to observe three iatls from deep space just four days after Perihelium. The observations were difficult. It took until February twenty twenty six for the data to reach Earth. And Issa has now published the findings and the headline number is extraordinary. Juice's Magis spectrometer detected two thousand kilograms of water vapor being expelled by three iatls every single second. Two thousand kilograms per second. To give you a sense of scale, that is the equivalent of approximately seventy Olympic swimming pools of water every single day, just evaporating off the surface of this comet into space, which. Tells you This is a very active comment. Water rich at least on the surface, though there's an interesting wrinkle. Its carbon dioxide to water ratio is higher than you typically expect from a Solar System commet, which either means the nucleus is genuinely CO two rich or there's a thick insulating crust hiding ice underneath. Either of which we can determine from here. Three iatls has now passed Jupiter and is heading out of the Solar System. It will never return. And here's the part I find most extraordinary. ESIS navigation camera, designed for navigating near Jupiter's moons looking at surfaces a few hundred kilometers below, also contributed to the science. It provided a unique vantage point from deep space that helped ESA's planetary Defense team refine a comet's orbital path to ten times better accuracy than Earth based observations alone. Could achieve an instrument designed for one job unexpectedly doing something completely different and doing it brilliantly. That is science at its best. What I keep coming back to is the age of three iatls. Based on his trajectory, this commet may be billions of years older than the Solar System itself. It's not just from another star. It may be older than our Sun. It has been traveling through interstellar space for longer than Earth has existed. And it spent about a year passing through our backyard, and we watched it as carefully as we could. And now it's gone. Everything we will ever know about three iatls we know. Already everything we will ever know. I love that and find it completely haunting an equal measure. Right after last week's heartbreak with Comet Maps the sun grazer that did not survive its close pass with the Sun, which we covered yesterday's episode, the good news is that April is not done with comets, not even close. Comet C twenty twenty five are three discovered by the Pan Stars survey is now the prime target for April skywatching, and it's looking genuinely promising. Where Maps was unpredictable and dramatic, Akretz sungrazer diving to within one hundred thousand miles of the Sun's surface, pand Stars is a more conventional comment predictable orbit, manageable approach, the reliable act that shows up when the headliner cancels. And its timing is good. Perry Helion closest approach to the Sun is around April twentieth. Closest approach to Earth is April twenty seventh, when it comes within about forty four million miles of US. At peak brightness, it's expected to reach approximately magnitude eight. Now magnitude eight means you will not see it with the naked eye under normal skies, but binoculars will absolutely do the job. Any small telescope will give you a lovely view. You're looking for a fuzzy smudge, possibly with a fan tail extending away from the Sun. For Northern Hemisphere listeners, look east in the pre dawn sky from mid April through the end of the month. It will be in the constellations Pegasus and Pisces. A good star app Delarium sky Safari star Walk two will give you exact positioning, and for our. Listeners in Australia and New Zealand, your window is actually in early May. In the evening sky. Look west after sunset. Dark skies will significantly help get away from city lights if you can. Coomet brightness predictions can shift. They famously don't always behave, so keep checking sky and Telescope or Universe today. As we get closer to perihelion. But right now the forecast looks encouraging. Think of it as the universe offering a constellation prize after maps. It's a perfectly lovely comment and it deserves our attention. One commet destroyed, one comet in coming April is very on brand for the Solar System. All right, story six, And today we're doing something a little different to close the show. We are going back thirty years, back to one of the strangest and most overlooked stories in the history of space exploration. A mission that was built with extraordinary ambition, launched into tragedy, and then vanished, and nobody has ever found it. This is the story of Mars ninety six. Let's set the scene. It's nineteen ninety six. The Cold War has been over for five years. Russia and the United States are, for the first time in decades, not rivals in space. They're partners. Juttle Mirror is underway, the International Space Station is being designed. There is genuine optimism about what a post Cold War space age could look like. And in that spirit of optimism, an extraordinary mission is being assembled. Russia is leading it, but it is genuinely Thai National science payloads from Germany, France, Italy, Poland, Spain, Belgium, Finland, Austria, and the United States, dasa's Jet Propulsion Lab contributing two instruments. This is what cooperation looks like when people choose it. The spacecraft itself is remarkable. At over six thousan five hundred kilograms, it is the largest interplanetary spacecraft humans had ever launched more than forty science instruments aboard, and its ambition is staggering. It would study Mars simultaneously from orbit, from the surface and from below it, from below it, from below it. Mars ninety six was carrying two surface penetrators, hardened cylindrical probe specifically engineered to strike the Martian ground at seventy to eighty meters per second and bury themselves several meters underground, where they would measure seismic activity and heat flow for up to a year. That is actually extraordinary a networked subsurface Mars science station. In nineteen ninety six. It was also carrying two surface landers, small autonomous stations that would descend using an air bag system to cushion their landing, an airbag landing concept that NASA's Mars Pathfinder would use to enormous public acclaim just months later. So the technology was there, the ambition was there, the international partnership was there, and on the night of November sixteenth, nineteen ninety six, the proton K rocket lifted off from Bikanor Cosmodrome. And then almost immediately something went catastrophically wrong. The spacecraft entered its parking orbit successfully. The upper stage was supposed to fire and push Mars ninety six toward interplanetary velocity. It didn't. It either failed to ignite properly or shut down almost immediately. And here's a detail that stays with me. The onboard autopilot kept executing its program sequence. It had no way of knowing the mission had already failed. So it separated from the upper stage. It fired its own engine, It unfolded its solar panels, it began transmitting toelemetry. For a brief moment, controllers in Crimea thought it had worked. The signals were there, the spacecraft was doing everything it was supposed to. Until the orbital data arrived and the realization set in. Mars ninety six had never left Earth orbit. It was trapped, and it was about to come back down very rapidly. Early assessments suggested the debris might land over Australia, which prompted President Clinton to call Prime Minister John Howard directly to offer support for any recovery operation. As tracking data was refined, the projected impact zone shifted, eventually settling on a corridor across the Eastern Pacific and into northern Chile and Bolivia. And in the Andes. That same night, witnesses reported something unusual, a brilliant object moving slowly across the sky, not the sudden flash of a meteor, something that lasted nearly a minute, jetting glowing fragments that briefly lit the thin mountain air before fading. One of those witnesses was an electronic specialist at the European Southern Observatory, who later said he had no illusions that it was anything other than a piece of space debris. US Space Command later acknowledged in writing, we believe it is reasonable that the impact was in fact on land. And then nothing. A search was never performed, nobody went looking. Thirty years later, the final resting place of Mars ninety six is completely. Unknown, and here is where it gets genuinely strange. Those surface penetrators built to survive striking Mars at seventy to eighty meters per second, had thick compact casings engineered for violent impact. It is entirely possible that one or both of them survived reentry and are sitting in the Andes right now, largely intact. Hardware built for Mars in a Chilean valley that nobody has ever looked for. The spacecraft was also carrying eighteen radio isotope heater units, small plutonium powered heaters specifically engineered to survive catastrophic events, including atmospheric re entry. Similar units survived the uncontrolled crash of a Soviet satellite over northern Canada in nineteen seventy eight, so these two could still be out there. The Space Review published a beautiful retrospective on this story just this week, and they put it perfectly. A spacecraft engineer to be tracked from hundreds of millions of kilometers away may instead have vanished somewhere on Earth, a world mapped in exquisite detail by satellites, aircraft, and ordinary people carrying cameras in their pockets, somewhere in a dry valley across the wind swept Altiplano or among the salt flats and volcanic slopes of the High On. This hardware built for another planet may still be lying quietly under open sky. Could we find it today with modern satellite imagery, drone surveys, AI pattern recognition. Why has nobody gone looking in thirty years? That is a question I genuinely don't have an answer to. There is a coda to this story that I think deserves to be said. Many of Mars ninety six's science teams didn't give up. They went on to contribute to isa's Mars Express mission, launched in two thousand and three, which is still operating today. And one instrument, the Alpha Proton X ray Spectrometer, developed by the Universe City of Chicago for Mars ninety six, actually reached Mars. A closely related version of it flew aboard NASA's Mars Pathfinder, launched just months after the crash. It landed on Mars in nineteen ninety seven and began returning chemical readings from the surface. One instrument made it, carrying forward the work of the mission that never got there. Somewhere in the Andes, hardware built for another planet sits silent and unfound, and somewhere on Mars, a cousin of that same hardware did exactly what it was built to do. The mission failed, the science and part survived. Russia has never successfully sent an independent Mars mission since Mars ninety six. Worth sitting with, especially this week as we watch Artemis two completing one of the most successful crude missions in decades. Base is hard. Every mission we celebrate, every safe return, every trajectory burn that fires on top time is built on decades of missions that didn't make it. Mars ninety six is one of them. And if you're ever in the andes, keep your eyes open. And that is Astronomy Daily for Wednesday, April eighth, twenty twenty six. What a lineup today. We had Artemis two heading home, a cargo ship delayed into a spectacular Friday, the origin story of the ground beneath your feet rewritten, an alien comment saying it's final farewell, a new comment arriving just in time, and a thirty year old mystery that nobody has solved. If you enjoyed today's episode, please subscribe wherever you get your podcasts. It genuinely makes a difference in helping us reach more Space enthusiasts around the world. Leave us a review, If you have a moment, tell a friend. Find us on social media. We are at astro Daily Pod on Twitter and x, Instagram, TikTok and YouTube links and full show notes at Astronomy Daily dot io. We will be back tomorrow with the latest from space. Until then, for Avery, I'm Anna and for Anna, I'm Avery, keep clicking up. We'll see you tomorrow Sunday. Star is the. Star Is Star