[HN Gopher] Detection of triboelectric discharges during dust ev...
___________________________________________________________________
Detection of triboelectric discharges during dust events on Mars
Research paper: https://www.nature.com/articles/s41586-025-09736-y
Author : domofutu
Score : 92 points
Date : 2025-11-26 19:26 UTC (5 days ago)
(HTM) web link (gizmodo.com)
(TXT) w3m dump (gizmodo.com)
| Razengan wrote:
| Does that mean Mars' ground is electrically charged (positively
| or negatively) or what?
| saagarjha wrote:
| I assume it's earthe-wait.
| wongarsu wrote:
| This discovery is thanks to Perseverance having microphones. It's
| crazy to think about that 2021 was the first time we had working
| microphones on Mars.
|
| The first Mars Microphone was originally supposed to land in 1999
| on the Polar Lander, but that one didn't survive the landing. The
| next was in 2008 on Phoenix 's Mars Descent Imager, but in
| integration testing a bug was discovered that made the Descent
| Imager risky to use, so that was never activated. And on all the
| rovers since then a microphone wasn't deemed important enough
| compared to all the other possible payloads
| zokier wrote:
| > The next was in 2008 on Phoenix 's Mars Descent Imager, but
| in integration testing a bug was discovered that made the
| Descent Imager risky to use, so that was never activated. And
| on all the rovers since then a microphone wasn't deemed
| important enough compared to all the other possible payloads
|
| There was exactly one Mars rover, Curiosity, between 2008 and
| Percy.
| chistev wrote:
| How does this work in practice. If a microphone is up there,
| it's constantly listening for things right?
|
| So how do humans here on Earth go over it to know if a sound
| was picked up knowing there's hours of recording?
|
| Is it that the whole system is programmed to show a spike when
| sound is captured?
| KeplerBoy wrote:
| Listening to hours of recording doesn't even seem like a lot
| considering this is the only microphone we have on another
| planet. You would need like 4 people doing this full time,
| which is a drop in the bucket for a project on this scale.
|
| Of course this is not how it's done and almost all of the
| recording will just be wind or noise from the rover itself,
| which can easily be filtered out.
| henrebotha wrote:
| This doesn't require anything fancy. I haven't used my sound
| engineering qualification in 14 years and I could do it by
| hand. You can visually scan through the recorded waveform and
| look for shapes that stand out. Simple audio processing
| techniques like using a noise gate to shut off the volume
| whenever the input level is below some configured threshold
| can make this even easier.
| bobmcnamara wrote:
| If you have enough RAM, start with a ring buffer.
|
| On interesting event: compress and transfer the relevant
| chunk of audio from the ring buffer back to Earth.
|
| Interesting event trigger ideas:
|
| 1) loud sound after quiet time
|
| 2) manual timestamp request from control
|
| 3) video clip recording
|
| 4) midnight, sunrise, noon, sunset. These are mostly so you
| have some daily baseline.
|
| 5) science package running
|
| 6) rover moving
|
| 7) abrupt camera change
| TeMPOraL wrote:
| I'd add:
|
| 8) Quiet but above-noise sound persisting for some time
| (might be worth checking out and then adjusting the cutoff
| level up, if it turns out to be more wind)
|
| 9) Complete silence (possibly malfunction) or sound levels
| dropping far below expected background (weird).
| Sharlin wrote:
| Well, there _are_ these things called computers, and they're
| really very good at this stuff. It's not exactly rocket
| science (heh) to write a program to listen to an audio stream
| and mark and log every occurence of something else than
| background noise and ambient wind sounds (if Martian winds
| are even loud enough to make sound). Everything else that the
| rover has to do automatically is way more complicated.
|
| It's pretty likely that the entire stream of silence isn't
| being stored, or sent to Earth, only the interesting parts.
| There isn't any way for people to listen in real time anyway,
| because communications (can) only happen at specific times of
| the day. Every interplanetary mission works by sending a
| preplanned sequence of commands one day, then coming back the
| next day to see what the probe/rover/whatever sent back, then
| planning the next set of commands, and so on.
| PunchyHamster wrote:
| it's wild given how small and light basic microphone is. They
| even (probably not in 1999 tho) come with their own adc and
| serial interface now.
|
| Then again I guess there isn't any obvious need for it aside
| from PR points for "listening to mars"
| foobarbecue wrote:
| Yes, and don't forget that you need to modify & certify it to
| work in 1% of Earth atmospheric pressure and down to -75C,
| and get it integrated into flight software running on a
| RAD750.
| retrac wrote:
| Bandwidth and storage.
|
| The Viking landers (1975) were very sophisticated with
| robotic arms and mass spectrometers, adorable little
| anemometers, digital colour cameras, the whole deal, with 5
| megabytes of digital tape storage.
|
| The downlink rate was 16 kbps when related by the matched
| orbiter; otherwise direct communication was at 250 bps.
|
| The digital cameras were pushing the absolute limit of
| technology at the time. The digitizer produced a 16 kbps
| bitstream that fed the uncompressed image directly to the
| transmitter taking four minutes to send an image. It could
| also be stored on tape for later transmission, but it used
| much of the tape to do so.
|
| If it had included a microphone and ADC, it would have been
| technically possible to record a few minutes of audio and
| then spend hours transferring it back to Earth. But the kind
| of constant monitoring now done really depends on the more
| than 1 Mbit/s of bandwidth now available thanks to half a
| dozen Martian orbiters, and all the fancy processors and
| gigabytes of storage the landers and rovers now have.
| foobarbecue wrote:
| > The first Mars Microphone was originally supposed to land in
| 1999 on the Polar Lander, but that one didn't survive the
| landing.
|
| This could be misread to mean that Mars Polar Lander landed but
| the microphones didn't survive. Mars Polar Lander crashed and
| was presumed completely destroyed on impact. Last I heard, we
| still haven't found the crash site in orbital imagery.
| throwawayffffas wrote:
| What blows my mind is that we had not before. I would think that
| with all that dust flying around it's got to be pretty common.
| And we have satellites orbiting Mars for decades and apparently
| we didn't see any.
| larodi wrote:
| ...perhaps resolution and FPS provided by these orbital cameras
| are not exactly what one would expect.
| irjustin wrote:
| This lightning is only a few centimeters long:
| https://www.kpbs.org/news/science-technology/2025/11/26/at-l...
| amelius wrote:
| Strange that the article doesn't say what this means for the
| formation of life.
| tsimionescu wrote:
| Does it mean anything? There are some theories that lightning
| could be involved in abiogenesis on Earth, but it's not in any
| way a clear thing.
| chistev wrote:
| What are the implications for life?
| stronglikedan wrote:
| same as before
| kadoban wrote:
| Vaguely positive for abiogenesis, but not in a way that really
| moves the needle at all.
| irjustin wrote:
| This isn't lightning like we think on earth. It's only a few
| centimeters long which is why it's never been detected before
| except by microphone[0].
|
| [0] https://www.kpbs.org/news/science-
| technology/2025/11/26/at-l...
| yesco wrote:
| Wouldn't it be static electricity in that case and not
| lightning? Not sure if this is just a technical definition
| thing I'm missing or if lightning just makes a cooler sounding
| headline.
| moron4hire wrote:
| Lightning _is_ static electricity that builds in an
| atmosphere.
| zamadatix wrote:
| And a mountain is a bump on the ground. It does feel like
| "lightning" comes with context beyond how the charge was
| formed, even if it could be technically correct to say
| that's all it is. Of course almost nobody knows what
| triboelectric discharge is either, but sticking to "static
| electricity" fits well between the two.
| nomel wrote:
| Lightning is a discharge of static electricity, but a
| discharge of static electricity is not lightning.
| moron4hire wrote:
| <sigh>
|
| In the atmosphere!
| nomel wrote:
| I think this is a mix of not having a word for this specific
| phenomenon, so inappropriately applying the closest, and the
| usual bad science reporting. They don't call it lighting in
| the actual paper, because not all discharge events are
| lightning.
| shevy-java wrote:
| Thor is there, swinging his ...
|
| hammer.
|
| Edit: Wait a moment ... that's not actually lightning?
|
| "By listening to the sounds of Mars, the team identified
| interference and acoustic signatures in the recordings that are
| characteristic of lightning."
|
| So they could only listen to sound? I mean, aren't pictures more
| convincing? We need more cameras on Mars.
| dgb23 wrote:
| Galvanizing!
| keepamovin wrote:
| I see waht you did there. But your comment is so subtle, it's
| boiling the frog of HN's humor reflex
| keepamovin wrote:
| How do we know it's not alien lightsaber battles tho?
___________________________________________________________________
(page generated 2025-12-01 23:01 UTC)