Astronauts in Limbo, Lunar Wonders, and the Discovery of New Moons: S04E62

Episode Transcript

Hello space enthusiasts! Today's headlines are packed with some big developments in astronomy and space exploration. We've got quite a line-up for you, from mission complications that affects the International Space Station to ground-breaking discoveries that are reshaping our understanding of the cosmos. We'll dive into the latest about a crucial NASA-SpaceX mission delay that's affecting two astronauts who've been waiting months to return home. Then, we'll explore an intriguing debate, or would that be a developing spat, over potential interstellar artifacts and what they might tell us about our cosmic neighborhood. Get ready for an enlightening discussion about tonight's lunar eclipse and its scientific significance, plus an absolutely stunning announcement about Saturn - our ringed giant has just gotten a lot more crowded with the discovery of over a hundred new moons. We'll also unravel the mystery behind a peculiar deep space radio signal and take a fascinating look at the powerful jets emanating from supermassive black holes. There's a lot to cover, so let's get started.

A critical NASA-SpaceX mission has hit an unexpected snag at Florida's Cape Canaveral Space Force Station, where a hydraulic ground issue forced controllers to postpone the much-anticipated Falcon 9 launch. This delay has particularly significant implications for two NASA astronauts, Suni Williams and Butch Wilmore, who have been stationed aboard the International Space Station far longer than originally planned. These veteran astronauts launched into space on June 5th, 2024, expecting an eight-day mission. However, as we well know, their stay has stretched to more than nine months after their Boeing spacecraft was deemed unsafe for return travel. The postponed SpaceX mission was meant to be their ticket home, potentially allowing them to return to Earth as early as Sunday.

The specific issue involved one of the launch pad's clamp arms, with engineers expressing concerns that it wouldn't open fully during launch. While there's another potential launch window available tomorrow, SpaceX hasn't yet confirmed whether the equipment will be ready in time. Despite their extended stay, both Williams and Wilmore have maintained remarkable composure about their situation. During a September news conference from the ISS, they emphasized their training to "expect the unexpected." Williams, age 58, even referred to the space station as her "happy place," though she admitted to missing her family and two dogs back on Earth.
Wilmore, 61, acknowledged their decision not to return on the Starliner spacecraft they arrived in, noting they weren't "comfortable" with that option given the technical issues. He highlighted that 90% of their training focused on preparing for unexpected situations, and they're willing to remain in orbit for as long as necessary to ensure a safe return. The extended mission has given Williams additional perspective on our home planet. As she poignantly noted, being in space has opened her mind to thinking differently about Earth, emphasizing that "It's the one planet we have and we should be taking care of it."

Now, an update to a story we brought you yesterday. An intriguing scientific debate has erupted in the astronomical community, centered around Harvard physicist Avi Loeb's bold claims about metallic spherules recovered from the seafloor near Papua New Guinea. Loeb suggests these tiny fragments might not just be from space, but potentially from an interstellar source – and more controversially, could be evidence of an alien civilization from another star system.

As we reported yesterday, the story begins with a meteor that blazed across the South Pacific Ocean on January 8th, 2014, tracked by the US Department of Defense. Last year, Loeb led a mission to recover fragments from this object, but his findings have met with significant skepticism from the scientific community. A team led by Johns Hopkins University researchers has particularly challenged the evidence, suggesting that what was thought to be seismic data from the meteorite's impact was actually caused by something far more mundane – a truck passing by the seismic station on Manus Island. However, Loeb maintains that the expedition's location was determined primarily by NASA's Center for Near Earth Object Studies' calculations of the meteor's trajectory, not the seismic data.

The controversy deepens when it comes to the composition of these recovered spherules. While Loeb's team argues that their chemical analysis rules out Earth-based contamination, other physicists contend that the only definitive proof of interstellar origin would come from dating the material and finding it to be older than our Sun. This debate highlights a fundamental tension in the search for extraterrestrial evidence – the challenge of distinguishing truly exotic materials from more conventional explanations. The scientific community continues to scrutinize these findings, emphasizing the importance of rigorous verification before making extraordinary claims about potential alien artifacts.

And here's another update...and reminder. Get ready for a spectacular celestial show coming up tonight, March 13th into the early morning hours of March 14th, as we'll witness a total lunar eclipse. During this event, our Moon will pass through Earth's shadow, transforming from its usual bright white glow to an eerie reddish hue – earning it the popular nickname "blood moon." But this isn't just a pretty light show in the sky. These eclipses have been teaching us about our world since ancient times. In fact, it was ancient Greek philosophers who first realized Earth must be round by observing the curved shadow it cast on the Moon during eclipses – one of humanity's earliest scientific breakthroughs from watching these events.

Today, lunar eclipses continue to be valuable scientific tools, particularly for studying Earth's atmosphere. That distinctive red color we see during totality happens because sunlight bends through our atmosphere before reaching the Moon. Our atmosphere filters out blues and greens, letting mostly red light through – the same process that gives us those gorgeous sunset colors. The Moon's appearance during eclipses can actually tell us about what's happening in our atmosphere. Sometimes it appears bright red, while other times it takes on a darker brownish-gray color, especially after major volcanic eruptions that have added particles to our atmosphere.

These events are also providing insights about the Moon itself. NASA's Lunar Reconnaissance Orbiter has made fascinating discoveries during previous eclipses, revealing that the lunar surface doesn't cool uniformly when it enters Earth's shadow. These temperature variations tell us about differences in the Moon's surface properties that we might otherwise miss. What makes lunar eclipses particularly special is their accessibility. Unlike solar eclipses that are only visible along a narrow path, lunar eclipses can be seen by everyone on the night side of Earth. This upcoming eclipse will be visible to more than a billion people. And if you're watching, keep your eyes peeled – during a 2019 eclipse, observers even caught glimpse of a meteor impact on the lunar surface.

In an extraordinary astronomical discovery, an international team of researchers has found 128 new moons orbiting Saturn, dramatically expanding our understanding of the ringed planet's satellite system. This breakthrough, confirmed by the Minor Planet Center just days ago, makes Saturn the undisputed champion of moons in our solar system, with a total of 274 known natural satellites. The team made these discoveries using the Canada France Hawaii Telescope, conducting observations between 2019 and 2021. They employed an innovative technique of combining multiple images to reduce noise and strengthen the signals from these previously undetected moons. Initially, they found 64 new moons, but follow-up observations in 2023 revealed even more.

What's particularly fascinating about these new moons is that they're all irregular moons, following wide, elliptical orbits that are often highly inclined. Unlike regular moons, such as our own Moon, which formed alongside their parent planet, these irregular moons were likely captured by Saturn's gravity. Even more intriguingly, scientists believe these moons are actually fragments from violent collisions that occurred in Saturn's past. The majority of these newly discovered moons are clustered near what's known as the Mundilfari group, suggesting this region was the site of a significant collision within the last 100 million years. This finding adds weight to the theory that Saturn's complex system of moons and rings is constantly evolving through a series of cosmic crashes and gravitational interactions.

Dr. Edward Ashton, who led the research, suggests that Jupiter, which currently has 95 confirmed moons, will likely never catch up to Saturn's impressive count. This discovery not only cements Saturn's position as the planet with the most moons but also provides valuable insights into how planetary systems evolve and interact over millions of years. For now, these new moons are identified by number sequences, but they'll eventually receive proper names following the tradition of naming Saturn's moons after Norse, Gallic, and Canadian Inuit gods. With this discovery, Saturn now hosts almost twice as many moons as all other planets in our solar system combined, truly making it the king of moons in our cosmic neighborhood.

In another fascinating breakthrough in space science, astronomers have finally cracked the case of a mysterious repeating radio signal that has puzzled researchers since its discovery last year. The signal, which pulses every two hours like clockwork, has been traced back to an unusual binary star system located about 1,600 light-years away in the direction of the Big Dipper. This cosmic duo consists of a white dwarf - the dense remnant of a dead star - and its companion, a red dwarf star. What makes this discovery particularly exciting is that it represents an entirely new source for these types of long-period radio bursts, which were previously only associated with neutron stars. The signal first appeared in data collected by the Low Frequency Array, or LOFAR, back in 2015. After its initial detection, researchers found six more pulses from the same source. These radio flashes can last anywhere from several seconds to a few minutes, but they maintain that precise two-hour regularity that caught astronomers' attention.
The team's detailed follow-up observations using the Multiple Mirror Telescope in Arizona and the McDonald Observatory in Texas revealed that these two stars are locked in an incredibly tight orbital dance, circling each other every 125.5 minutes. The interaction between their magnetic fields appears to be the source of these radio pulses, as they slam together during their cosmic waltz. What's particularly intriguing about this system is that while it shares some similarities with fast radio bursts, or FRBs, these pulses are distinctly different. They have lower energy levels and last much longer than typical FRBs, which usually flash for just milliseconds. This discovery opens up new possibilities for understanding the variety of radio signals we detect from space and suggests there might be many more such systems waiting to be found.

This breakthrough not only solves a compelling cosmic mystery but also provides astronomers with a new category of objects to study as they work to understand the complex interactions between stars in binary systems. The team is now planning to study the system's high-energy ultraviolet emissions, which could reveal even more details about this fascinating stellar partnership.

Next, let's dive into some groundbreaking research about supermassive black holes and their incredible cosmic fountains. Nearly every large galaxy in our universe harbors one of these cosmic giants at its center, including our own Milky Way with its black hole, Sagittarius A star. These objects are the densest known in the universe, with masses that can reach billions of times that of our sun.

What's particularly fascinating is what happens when these sleeping giants "wake up." When a neighboring galaxy supplies fresh gas and dust, these black holes spring into action, but it's far from a peaceful process. As they consume this cosmic material, it becomes superheated to temperatures millions of degrees hotter than our sun's surface. This superheated matter doesn't just disappear quietly – it gets ejected from the galaxy at speeds approaching that of light, creating spectacular jets that resemble enormous cosmic fountains.
These high-speed plasma jets produce radio signals that we can detect with powerful telescopes, earning their host galaxies the name "radio galaxies." But here's the thing – while black holes are common, radio galaxies are relatively rare, making up only about 10 to 20 percent of all galaxies. Even more exceptional are the giant radio galaxies, which represent just 5 percent of all radio galaxies. These cosmic behemoths can produce jets stretching an astounding 16 million light-years – that's nearly six times the distance between our galaxy and Andromeda. The largest known jet spans an incredible 22 million light-years. Recent research using sophisticated computer simulations has helped us understand how these massive structures form and evolve. By creating models that follow the fundamental laws of physics, scientists can now track how these jets develop over hundreds of millions of years – something we could never observe directly in real time. These simulations suggest that these cosmic fountains play a crucial role in maintaining the balance of our universe, preventing galaxy clusters from collapsing under their own gravity by heating the surrounding gas.

The most exciting part? Scientists believe there could be thousands more giant radio galaxies yet to be discovered. Thanks to powerful telescopes like MeerKAT and LOFAR, combined with advanced supercomputing capabilities, we're continuing to uncover new secrets about these fascinating cosmic phenomena.

And that brings us to the end of today's fascinating journey through space. I'm Anna, and thank you for joining me on Astronomy Daily. From so called stranded astronauts awaiting their return from the ISS, to Saturn's incredible new family of moons, and the mysterious binary system creating those puzzling radio signals, we've covered quite a bit of cosmic ground today.

If you'd like to dive deeper into any of these stories or stay up to date with the latest developments in space and astronomy, visit us at astronomydaily.io. There you can sign up for our free daily newsletter and access our constantly updating newsfeed. You'll also find all our previous episodes available for listening at your convenience. Want to join our growing community of space enthusiasts? You can find us across social media - just search for AstroDailyPod on Facebook, X, YouTube, YouTube Music, TikTok, and our new Instagram account. And speaking of our community, I want to extend a special thank you to all our early followers who've joined us on this cosmic journey. Your support means the world to us.

Until next time, keep looking up and wondering about the mysteries of our universe. This is Anna, signing off from Astronomy Daily.