Are We Missing Alien Signals? Space Weather, Brain Changes and the Mars Life Question

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Welcome to Astronomy Daily. I'm Anna.


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>> And I'm Avery. It's Monday, March 9th.


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And if you've been following the news


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this past week, the universe has been


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spectacularly busy.


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>> We've got alien signals going missing in


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the cosmic static. Astronaut brains


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getting physically rearranged in space,


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a dramatic launchpad rescue story


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straight out of a thriller, and a


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genuinely mindbending discovery about


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why Earth's seasons work the way they


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do. Plus, we're asking one of


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astrobiologyy's most provocative


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questions. Did life on Earth actually


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start on Mars? It's a packed episode.


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Let's get into it.


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>> Here's a thought that's going to sit


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with you for a while. What if we're not


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alone in the universe, but we've been


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tuning to the wrong frequency this whole


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time?


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>> That's essentially what a new study from


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SETI is suggesting. Researchers Vishal


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Gajar and Grace Brown have published


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work showing that stellar space weather,


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the kind of turbulent plasma and solar


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activity that stars constantly turn out,


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could physically distort alien radio


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signals before they even leave their


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home solar system. So, here's how SETI


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searches typically work. For decades,


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scientists have been scanning the sky


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for very tightly focused narrowband


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radio signals. Extremely specific


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frequencies that nothing natural in the


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universe should produce. If you detect


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one of those, the thinking goes, it's


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almost certainly artificial. It's almost


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certainly someone. And that logic is


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still sound, but the new research


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highlights a gap in the reasoning. Even


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if an alien civilization sends a


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perfectly clean narrowband signal, their


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own stars environment might smear it out


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before it escapes. Plasma density


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fluctuations and stellar winds or a


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burst from a coronal mass ejection can


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spread that tight signal across a much


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wider range of frequencies, reducing its


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strength at any single point below what


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our detectors can pick up. The team ran


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simulations of the million closest


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sunlike and red dwarf stars and found


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that 70% of stars would broaden a signal


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by more than one hertz, 30% by more than


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10 hertz. And if a coronal mass ejection


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happened to fire off at the moment of


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transmission, the broadening could


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exceed 1,000 hertz, making the signal


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essentially invisible to the way we


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currently search.


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>> And red dorp stars are the biggest


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culprits here. And that's particularly


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significant because red dwarfs make up


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about 3/4 of all the stars in the Milky


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Way. A lot of our SETI attention has


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focused on those systems precisely


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because they're so common. And it turns


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out they may also be the most likely to


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garble any messages being sent from


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their planets. The good news is that


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identifying the problem is the first


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step to solving it. The team says this


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gives us a framework for redesigning


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searches to remain sensitive even when


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signals are broadened to look for what


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actually arrives at Earth rather than


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what was originally transmitted.


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>> It's a bit like realizing you've been


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trying to tune into a radio station, but


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the signal had passed through a foggy


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atmosphere on its way to you. It's not


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that the station isn't broadcasting.


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It's that we need a better aerial.


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>> And that's a much more hopeful framing


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than nobody's out there. The universe


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might be full of voices we just haven't


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learned to hear yet.


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>> Now, if you're planning a trip to space


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or if you're just a big Aremis fan, this


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next story is worth paying attention to.


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Though, we want to say upfront that it's


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fascinating rather than alarming.


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>> A new study published in the proceedings


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of the National Academy of Sciences has


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found that spaceflight doesn't just


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change your perspective on life. It


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literally shifts the physical position


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of your brain inside your skull. A team


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led by Rachel Sidler at the University


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of Florida analyzed MRI scans from 26


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astronauts taken before and after


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missions to the ISS. Missions ranging


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from a few weeks to over a year. To


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measure the brain's actual movement,


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they aligned each person's skull across


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the two scans so they could track the


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brain's position relative to the bone


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itself.


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>> And what they found was striking. The


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brain shifts upward and backward inside


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the skull. It also physically deforms,


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stretching and compressing in different


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directions. The sensory and motor


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regions show the largest shifts. And


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crucially, the longer someone spent in


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space, the more pronounced these changes


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were.


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>> The underlying cause is what you'd


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expect from microgravity. On Earth,


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gravity constantly pulls fluids,


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including the cerebral spinal fluid


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surrounding your brain, downward. In


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space, that force disappears. Fluid


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redistributes towards the head. The


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brain effectively floats in the skull


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and it responds to different forces from


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surrounding tissues.


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>> Previous research already knew the brain


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shifts upward in space. What makes this


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study important is the level of detail.


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Instead of treating the brain as one


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object, the team divided it into more


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than 100 regions and tracked each


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individually. that revealed patterns


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like opposing lateral shifts on each


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side of the brain that had been


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canceling each other out and going


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unnoticed in whole brain averages. The


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reassuring news, most of the changes


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recover within 6 months of returning to


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Earth, and the astronauts themselves


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didn't report symptoms like headaches or


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cognitive fog. The researchers stressed


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that this doesn't mean people shouldn't


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go to space. But as missions get longer


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and as Aremis starts taking humans back


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to the moon and eventually towards Mars,


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understanding these effects will be


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important for designing proper


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countermeasures.


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>> It's a reminder that space is a


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genuinely alien environment for the


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human body. We evolved under one gravity


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and every time we leave it, we're


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running an experiment on ourselves. The


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more we understand those experiments,


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the safer we can make longduration space


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flight. Now for a story that is in the


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best possible way a bit of a thriller.


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In November last year, something went


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wrong at the historic Biconor Cosmodrome


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in Kazakhstan and nobody was entirely


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sure it could be fixed in time.


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>> It started on November 27th, 2025. A


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Soyuse rocket lifted off from launch


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site 31 carrying the Soyuse MS28


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spacecraft with two Rose Cosmos


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cosminauts and NASA astronaut


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Christopher Williams aboard. The launch


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was successful. The crew docked with the


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ISS without incident,


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>> but post-launch inspection footage


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revealed significant damage to the pad


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itself. A component called the service


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cabin, which retracts into a protective


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cavity to shield it from engine exhaust


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during ascent, hadn't been properly


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secured. The powerful rocket exhaust,


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dislodged it, and the structure fell


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several meters into the launch trench,


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deforming bridges, access walkways, and


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other critical infrastructure. The space


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community was skeptical this could be


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fixed quickly. These are heavy, complex


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structures, but Rose Cosmos committed to


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the repair. And it turns out their long


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history with the Soyuse system gave them


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an unexpected advantage. Bare service


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cabins had been sitting in storage, left


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over from refurbishment plans dating


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back to the 1970s.


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>> The restoration effort was enormous.


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Over 150 personnel worked on the


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project. They completed over 250 m of


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welding, painted nearly 2400 square


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meters of structures, replaced all


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fastening units, and fully updated the


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electrical systems. The replacement


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cabin, originally built for an older


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Soyuse variant, needed modifications to


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work with modern hardware.


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>> And in under two months from the initial


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damage assessment, far faster than most


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observers anticipated, Rose Cosmos


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announced the pad was fully restored and


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declared ready for operations. That


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means Progress MS33, an uncrrewed cargo


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ship, is now cleared to launch from site


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31 on March 22nd. It will deliver around


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2.5 tons of supplies to the ISS.


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Propellant, water, food, scientific


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equipment, and crew parcels.


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>> It's a genuinely impressive piece of


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engineering under pressure. And it's a


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good reminder that behind every rocket


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launch is an enormous amount of


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groundwork. literally in this case that


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never makes headlines until something


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goes sideways.


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>> Okay, pop quiz. Why do we have seasons?


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>> Earth's axial tilt. We all learned this


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in school. When the northern hemisphere


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is tilted toward the sun, it's summer up


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here. When it's tilted away, it's


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winter.


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>> Exactly right. And most people also know


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that Earth's orbit around the sun is


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slightly elliptical. We're a bit closer


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to the sun in January and a bit farther


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away in July, but we're usually told


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that effect is minor and it doesn't


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significantly change our seasons. Well,


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a new study published in Nature suggests


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we may have been underelling that


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distance effect quite significantly. The


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research led by John Chiang at UC


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Berkeley focuses on a specific feature


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of the Pacific Ocean called the cold


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tongue. A strip of cooler water that


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stretches westward from South America


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along the equator. This cold tongue is


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closely tied to El Nino and Lania cycles


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which influence rainfall, drought, and


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weather patterns across huge swaths of


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the planet. What Chang and his


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colleagues found is that the changing


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Earth's sun distance creates its own


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separate annual cycle in the cold


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tongue, distinct from the tilt-driven


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one. And the two cycles are slightly out


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of sync. The distance-based one runs


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about 25 minutes longer than the


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tilt-based one. That doesn't sound like


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much, but it means that over about


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11,000 years, the two effects drift from


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being perfectly in phase to perfectly


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out of phase. When they're in phase,


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like they are roughly today, the effects


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reinforce each other. When they're out


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of phase, as they were around 6,000


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years ago, they partially cancel,


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producing a much weaker seasonal cycle


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in the cold tongue. And since the cold


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tongue drives El Nino, that means El


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Nino patterns themselves would have been


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dramatically different in the deep past.


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>> The mechanism works in a


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counterintuitive direction, too. While


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axial tilt creates north south


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temperature differences, the distance


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effect creates an east west contrast


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between the continental hemisphere of


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the Americas, Africa, and Eurasia and


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the ocean dominated Pacific side. That


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contrast drives trade winds which in


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turn shape the cold tongue.


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>> It's worth noting the study is entirely


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modelbased. It's a prediction that will


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need observational verification, but it


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opens fascinating questions for


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paleoclimate science. If Earth's orbital


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shape was changing the cold tongue over


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22,000year cycles, some ancient climate


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records may need reinterpretation. And


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there's something wonderfully humbling


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about it. We've been telling school


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children for generations exactly why


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seasons happen. And it turns out the


00:11:01.920 --> 00:11:04.389
full picture involves a subtle cosmic


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clockwork we hadn't fully accounted for.


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>> And now for our final story today, and


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honestly one of the most mindbending


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things you can contemplate on a Monday.


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What if you're not from Earth


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>> in a very literal biological sense?


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Possibly.


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>> A new study is revisiting the concept of


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panspermia. the idea that life doesn't


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necessarily originate independently on


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each planet, but can travel between


00:11:29.839 --> 00:11:33.030
worlds and the vehicle asteroid impacts.


00:11:33.040 --> 00:11:35.190
>> Here's the premise. We know that when a


00:11:35.200 --> 00:11:37.829
large asteroid or comet slams into a


00:11:37.839 --> 00:11:40.310
planet with enough force, it can blast


00:11:40.320 --> 00:11:43.430
material into space, rocks, dust, and


00:11:43.440 --> 00:11:45.670
potentially anything living inside those


00:11:45.680 --> 00:11:48.150
rocks. We've actually found meteorites


00:11:48.160 --> 00:11:50.630
on Earth that originated on Mars,


00:11:50.640 --> 00:11:53.590
blasted off by ancient impacts. So, the


00:11:53.600 --> 00:11:56.150
physical pathway definitely exists.


00:11:56.160 --> 00:11:58.389
>> The question has always been, could


00:11:58.399 --> 00:12:00.710
anything survive that journey? You're


00:12:00.720 --> 00:12:03.190
talking about the ejection itself, an


00:12:03.200 --> 00:12:05.750
enormous shock wave, then exposure to


00:12:05.760 --> 00:12:07.990
the vacuum and radiation of space for


00:12:08.000 --> 00:12:10.790
potentially millions of years, then a


00:12:10.800 --> 00:12:13.829
fiery atmospheric entry, and high-speed


00:12:13.839 --> 00:12:15.829
impact at the destination.


00:12:15.839 --> 00:12:17.670
>> The new research suggests the answer


00:12:17.680 --> 00:12:19.430
might be yes. under the right


00:12:19.440 --> 00:12:21.829
conditions. Some microbes, particularly


00:12:21.839 --> 00:12:24.069
those that form hardy spores or live


00:12:24.079 --> 00:12:26.230
deep within rocks, could potentially


00:12:26.240 --> 00:12:28.629
survive all of those stages. The rock


00:12:28.639 --> 00:12:30.629
itself provides shielding from radiation


00:12:30.639 --> 00:12:32.629
during transit. And the numbers game


00:12:32.639 --> 00:12:35.190
matters. Even if only a tiny fraction of


00:12:35.200 --> 00:12:37.509
ejected material survives, the sheer


00:12:37.519 --> 00:12:39.670
volume of material blasted around the


00:12:39.680 --> 00:12:42.150
early solar system means some viable


00:12:42.160 --> 00:12:44.389
biology could have made the crossing.


00:12:44.399 --> 00:12:46.870
>> The Mars connection is particularly


00:12:46.880 --> 00:12:49.509
intriguing. Early Mars was by many


00:12:49.519 --> 00:12:51.750
accounts a better candidate for life to


00:12:51.760 --> 00:12:54.870
emerge first than early Earth. It cooled


00:12:54.880 --> 00:12:57.750
faster. It had liquid water earlier. And


00:12:57.760 --> 00:13:00.230
it had a gentler gravitational well,


00:13:00.240 --> 00:13:02.790
making it easier for material to escape.


00:13:02.800 --> 00:13:05.509
If life arose on Mars billions of years


00:13:05.519 --> 00:13:08.150
ago and hitched a ride on an impact


00:13:08.160 --> 00:13:10.629
ejected rock, Earth could effectively


00:13:10.639 --> 00:13:12.870
have been seated. which would mean that


00:13:12.880 --> 00:13:15.110
if we ever find microbial life on Mars


00:13:15.120 --> 00:13:17.590
or evidence of ancient life there, we'd


00:13:17.600 --> 00:13:19.350
face a fascinating interpretive


00:13:19.360 --> 00:13:21.990
challenge. Did life arise independently


00:13:22.000 --> 00:13:24.710
on both worlds or are we all in some


00:13:24.720 --> 00:13:27.350
deep ancestral sense Martians?


00:13:27.360 --> 00:13:29.670
>> The study emphasizes this is still


00:13:29.680 --> 00:13:32.470
highly speculative. Hence Bermia remains


00:13:32.480 --> 00:13:35.110
a hypothesis rather than established


00:13:35.120 --> 00:13:37.590
science. But as our ability to study


00:13:37.600 --> 00:13:39.990
Martian samples improves, especially


00:13:40.000 --> 00:13:42.710
with future sample return missions, we


00:13:42.720 --> 00:13:45.110
may eventually be in a position to test


00:13:45.120 --> 00:13:46.389
it directly.


00:13:46.399 --> 00:13:48.389
>> Either way, the question is deeply


00:13:48.399 --> 00:13:50.389
fascinating and it gives a whole new


00:13:50.399 --> 00:13:53.190
flavor to the phrase out of this world.


00:13:53.200 --> 00:13:55.829
>> That's Astronomy Daily for Monday, March


00:13:55.839 --> 00:13:58.790
9th. From scrambled alien signals to


00:13:58.800 --> 00:14:01.189
astronaut brains, from a launchpad


00:14:01.199 --> 00:14:03.750
resurrection to the hidden clockwork of


00:14:03.760 --> 00:14:06.150
Earth's seasons, and the possibility


00:14:06.160 --> 00:14:08.710
that we're all secretly from Mars.


00:14:08.720 --> 00:14:10.550
>> It's been a great episode. If you're


00:14:10.560 --> 00:14:12.150
enjoying the show, please leave us a


00:14:12.160 --> 00:14:14.150
review wherever you listen. It genuinely


00:14:14.160 --> 00:14:16.389
helps new listeners find us. And share


00:14:16.399 --> 00:14:18.150
an episode with a friend who's curious


00:14:18.160 --> 00:14:19.350
about the universe.


00:14:19.360 --> 00:14:22.069
>> You can find us at astronomyaily.io


00:14:22.079 --> 00:14:25.670
IO and we're @ Astro Daily Pod on X,


00:14:25.680 --> 00:14:28.629
Instagram, Tik Tok, YouTube, and Tumblr.


00:14:28.639 --> 00:14:30.389
>> We'll be back tomorrow with more of the


00:14:30.399 --> 00:14:32.790
universe's greatest hits. Until then,


00:14:32.800 --> 00:14:33.829
keep looking up.


00:14:33.839 --> 00:14:45.910
>> Bye for now.


00:14:45.920 --> 00:14:49.639
Stories told.