Speaker 1: Welcome to Astronomy Daily.
Speaker 2: I'm excited to bring you another fascinating day of space
Speaker 2: and astronomy news. There's quite a bit to cover today,
Speaker 2: from orbital drama to seasonal changes on the Red planet.
Speaker 2: We'll start with a concerning development in Earth orbit, where
Speaker 2: a retired military weather satellite has broken up into dozens
Speaker 2: of pieces, adding to a pattern of similar incidents with
Speaker 2: these particular spacecraft. Then we'll look ahead to SpaceX's upcoming
Speaker 2: Bandwagon two mission, which will carry an impressive array of
Speaker 2: thirty different payloads into orbit, including an advanced.
Speaker 1: Radar satellite for South Korea.
Speaker 2: We'll also take a journey to Mars, where NASA's Mars
Speaker 2: Reconnaissance Orbiter has been capturing some incredible seasonal phenomena. Unlike
Speaker 2: Earth's gentle seasonal transitions, Mars experiences some remarkably explosive changes
Speaker 2: during its spring thaw, and I can't wait to tell
Speaker 2: you all about them. Plus, we've got to look at
Speaker 2: a new theory about that mysterious dark energy, and we'll
Speaker 2: revisit an age old debate with some new research.
Speaker 1: So let's get started.
Speaker 2: In a concerning development, the US Space Force has reported
Speaker 2: that a defunct military weather satellite experienced what they're calling
Speaker 2: a low velocity fragmentation event on December eighteenth. The incident
Speaker 2: occurred at an altitude of about eight hundred and forty kilometers,
Speaker 2: creating more than fifty pieces of trackable debris, according to
Speaker 2: radar observations from commercial space monitoring company Leo Labs. The
Speaker 2: satellite in question, known as DMSP five D two F fourteen,
Speaker 2: was launched back in nineteen ninety seven as part of
Speaker 2: the Defense Meteorological Satellite Program. After serving its purpose for
Speaker 2: over two decades, it was retired in twenty twenty, but
Speaker 2: remained in its Sun synchronous orbit. Weighing about seven hundred
Speaker 2: and fifty kilograms, this spacecraft is now the latest in
Speaker 2: a series of similar satellites to meet this unfortunate fate.
Speaker 2: What's particularly concerning is that this isn't an isolated incident.
Speaker 2: Several other satellites from the same family have experienced similar
Speaker 2: breaks make ups over the years. In October twenty sixteen,
Speaker 2: the F twelve satellite broke apart, following the fragmentation of
Speaker 2: F thirteen. In February twenty fifteen, going back even further,
Speaker 2: the F eleven spacecraft created fifty six pieces of tracked
Speaker 2: debris when it broke up in two thousand four. The
Speaker 2: root cause appears to be a known design flaw in
Speaker 2: these satellites battery assemblies that makes them vulnerable to explosion.
Speaker 2: This issue isn't limited to military satellites either. Similar civilian
Speaker 2: weather satellites operated by Noah have suffered the same fate,
Speaker 2: with Noah sixteen breaking up in twenty fifteen and Noah
Speaker 2: seventeen following suit in twenty twenty one. Most troubling is
Speaker 2: that these breakups occurred despite attempts to prevent them through
Speaker 2: a process called passivation, where satellites are prepared for decommissioning
Speaker 2: by draining their batteries and venting fuel tanks.
Speaker 1: Industry experts note.
Speaker 2: That this process may not be fully effective on older
Speaker 2: satellites that were designed before modern orbital debris mitigation practices
Speaker 2: were established. Next up, SpaceX is gearing up for an
Speaker 2: exciting ride share mission from Vandenberg Space for Space in California.
Speaker 2: The Bandwagon two mission, scheduled for a three thirty four
Speaker 2: am Pacific launch on December twenty first, will carry an
Speaker 2: impressive array of thirty different payloads to orbit the Star
Speaker 2: of this mission is a sophisticated radar satellite for South Korea,
Speaker 2: capable of seeing through clouds and darkness to capture detailed
Speaker 2: images of Earth. This spacecraft is part of South Korea's
Speaker 2: four hundred and twenty five project, a constellation of military
Speaker 2: Earth observation satellites that combines both optical and radar imaging capabilities.
Speaker 2: Among the other fascinating payloads are two satellites from Ice
Speaker 2: that will join their radar imaging constellation, and a trio
Speaker 2: of satellites from Hawkeye three hundred and sixty that will
Speaker 2: work together to pinpoint radio frequency transmissions from orbit. Two
Speaker 2: compact weather satellites from tomorrow dot Io will collect valuable
Speaker 2: atmospheric data, while LIZZISATI will test out new imaging and
Speaker 2: computing technologies in space. The mission will use Falcon nine
Speaker 2: booster B one THY seventy one, making its twenty first flight.
Speaker 2: After sending its passengers on their way, the booster will
Speaker 2: return to land at landing Zone four, right next to
Speaker 2: its launch pad. The second stage will perform a carefully
Speaker 2: choreographed series of burns to deploy the satellites at two
Speaker 2: different altitudes, most at five hundred and ten kilometers and
Speaker 2: the South Korean satellite at five hundred and seventy kilometers.
Speaker 2: This launch represents SpaceX's one hundred thirty first Falcon mission
Speaker 2: of the year, marking an incredibly busy period for the company.
Speaker 2: It's also their second dedicated ride share mission to a
Speaker 2: mid inclination orbit, specifically chosen to keep these satellites positioned
Speaker 2: over more populated areas of our planet rather than following
Speaker 2: the polar orbits typically used for Earth observation missions. After deployment,
Speaker 2: these satellites will begin their diverse missions from Earth imaging
Speaker 2: and weather monitoring, to testing new space technologies and providing
Speaker 2: communications serve vises. Together, they represent a remarkable snapshot of
Speaker 2: the increasing variety and capability of small satellites being launched today.
Speaker 2: Ever thought about the concept of seasons on other planets.
Speaker 2: While we're celebrating the approaching new year here on Earth,
Speaker 2: Mars has already completed its journey around the Sun, marking
Speaker 2: the end of its six hundred and eighty seven Earth
Speaker 2: Day year this past November. But unlike Earth's northern winter
Speaker 2: wonderland or southern hemispheres summer, Mars is experiencing a spectacular
Speaker 2: spring awakening that's far more dramatic than anything we see
Speaker 2: here at home. Instead of gentle snow melt and trickling streams,
Speaker 2: Mars puts on an explosive show. The red planet's thin
Speaker 2: atmosphere means ice doesn't gradually melt into liquid. It transforms
Speaker 2: directly into gas in a process called sublimation. This creates
Speaker 2: some truly remarkable phenomena that NASA's Mars Reconnaissance orbiter has
Speaker 2: been tracking for nearly two decades. One of the most
Speaker 2: dramatic events are the frost avalanche. Imagine witnessing a massive
Speaker 2: chunk of carbon dioxide frost wider than a house, breaking
Speaker 2: free and tumbling down Martian cliffs. The orbiter's high resolution
Speaker 2: cameras actually captured one of these spectacular events, showing a
Speaker 2: sixty six foot wide block of dry ice in freefall.
Speaker 2: But that's just the beginning. As spring temperatures rise, pressurized
Speaker 2: carbon dioxide gas builds up beneath the surface ice until
Speaker 2: it literally explodes upward, creating powerful geysers that blast dark
Speaker 2: fans of sand and dust into the Martian sky. These
Speaker 2: explosive jets leave behind distinctive patterns in the soil that
Speaker 2: when viewed from orbit, look remarkably like giant spider legs
Speaker 2: etched into the surface. Perhaps most impressive is the planet's
Speaker 2: northern ice cap, a structure as large as Texas that
Speaker 2: features enormous spiral troughs carved by powerful seasonal winds. Some
Speaker 2: of these troughs stretch as long as California, dwarfing similar
Speaker 2: features found in Antarctica. As the spring thaw begins, these
Speaker 2: channels become super highways for warm wind gusts that gain
Speaker 2: speed and heat as they race downhill. These same winds
Speaker 2: are constantly reshaping Mars's landscape, particularly its sand dunes. During winter,
Speaker 2: carbon dioxide frost locks these dunes in place, but once
Speaker 2: spring arrives and the frost sublimates, they begin their slow
Speaker 2: migration across the Martian surface. It's a seasonal dance that's
Speaker 2: been ongoing for eons, sculpting and reshaping the face of
Speaker 2: our neighboring planet. What makes this even more fascinating is
Speaker 2: that each Martian spring is unique, with subtle variations in
Speaker 2: temperature and timing creating different patterns of sublimation and surface activity.
Speaker 2: It's a reminder that Mars, despite its apparent desolation, is
Speaker 2: a dynamically changing world with its own distinctive seasonal rhythm. Now,
Speaker 2: let's dive into a topic that's been puzzling scientists for
Speaker 2: decades dark energy. For years, the term dark energy has
Speaker 2: been used to describe the mysterious force believed to drive
Speaker 2: the accelerated expansion of our universe. It's thought to make
Speaker 2: up about two thirds of the universe's total mass energy content. However,
Speaker 2: recent research from the University of Canterbury in christ Church,
Speaker 2: New Zealand challenges this long standing concept. Led by Professor
Speaker 2: David Wiltshire, the team analyzed supernova light curves with enhanced precision.
Speaker 2: Their findings suggest that the universe's expansion isn't uniform, but
Speaker 2: rather lumpy, varying in different regions. This challenges the conventional
Speaker 2: lambda cold dark matter model, which relies on dark energy
Speaker 2: to explain the universe's accelerating expansion. The researchers propose an alternative,
Speaker 2: the timescape model. This model considers that gravity affects time,
Speaker 2: causing clocks and regions with different gravitational strengths to tick
Speaker 2: at varying rates. For instance, a clock in the emptiness
Speaker 2: of space would run faster than one within a galaxy.
Speaker 2: These time differences could lead to the perception of an
Speaker 2: accelerating universe without invoking dark energy. Professor Wiltshire explains our
Speaker 2: findings show that we do not need dark energy to
Speaker 2: explain why the universe appears to expand at an accelerating rate.
Speaker 2: He suggests that what we've been interpreting as dark energy
Speaker 2: might actually be variations in the kinetic energy of expansion
Speaker 2: influenced by the universe's lumpy structure. This perspective also offers
Speaker 2: insights into the Hubble tension, the discrepancy between the current
Speaker 2: expansion rate of the universe and predictions based on early
Speaker 2: universe observations. By accounting for regional variations and expansion, the
Speaker 2: Timescape model could bridge this gap. While these findings are compelling,
Speaker 2: they don't entirely dismiss the existence of dark energy. Instead,
Speaker 2: they encourage a reevaluation of our cosmological models and highlight
Speaker 2: the importance of considering the universe's complex structure in our calculations.
Speaker 2: As we continue to explore these cosmic mysteries, each discovery
Speaker 2: brings us closer to understanding the true nature of our universe.
Speaker 2: It's a thrilling reminder of how much there is yet
Speaker 2: to learn. Finally, today, let's revisit a classic debate, what
Speaker 2: really caused the extinction of the dinosaurs. For decades, scientists
Speaker 2: have pondered whether massive volcanic eruptions or a catastrophic meteorite
Speaker 2: impact led to the dinosaur's demise. Recent research from utrect
Speaker 2: University and the University of Manchester sheds new light on
Speaker 2: this mystery. The study focuses on the Deccan Traps in India,
Speaker 2: where colossal volcanic eruptions occurred around sixty six million years ago.
Speaker 2: These eruptions released vast amounts of sulfur and carbon dioxide,
Speaker 2: potentially altering the global climate. By analyzing fossil molecules from
Speaker 2: ancient peats in the United States, scientists reconstructed air temperatures
Speaker 2: during this period. They discovered that a significant volcanic eruption
Speaker 2: about thirty thousand years before the meteorite impact caused a
Speaker 2: global cooling of approximately five degrees celsius. However, temperatures rebounded
Speaker 2: twenty thousand years before the impact, likely due to volcanic
Speaker 2: CO two emissions. This timeline suggests that while these volcanic
Speaker 2: events had drastic consequences, for life on Earth. Their climatic
Speaker 2: effects had dissipated thousands of years before the chi Salub
Speaker 2: meteorite struck. Therefore, the meteorite impact remains the primary culprit
Speaker 2: behind the mass extinction event that wiped out the dinosaurs.
Speaker 2: Lauren O'Connor of Utrecht University notes these volcanic eruptions and
Speaker 2: associated CO two and sulfur releases would have had drastic
Speaker 2: consequences for life on Earth, but these events occurred millennia
Speaker 2: before the meteorite impact and probably played only a small
Speaker 2: part in the extinction of dinosaurs. This research underscores the
Speaker 2: catastrophic impact of the Chisalub meteorite, which unleashed wildfires, earthquakes, tsunamis,
Speaker 2: and an impact winter that blocked sunlight and devastated ecosystems.
Speaker 2: Understanding these events helps us piece together Earth's complex history
Speaker 2: and the factors that have shaped life on our planet.
Speaker 2: It's a fascinating reminder of the dynamic forces at play
Speaker 2: over geological timescales, and that wraps up today's fascinating journey
Speaker 2: through space, from Earth orbiting satellite breakups to SpaceX's ambitious
Speaker 2: ride share mission and the dramatic spring spectacle unfolding on Mars.
Speaker 2: I'm Anna and I hope you've enjoyed this episode of
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Speaker 2: We'd love to hear your thoughts on today's stories and
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Speaker 2: spending time with us today exploring the wonders of space.
Speaker 2: Until next time, keep looking up and stay curious about
Speaker 2: our cosmic neighborhood.
Speaker 1: Sunny Day Star is so.
Speaker 2: Star is Star