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A dust devil looks a bit like a tornado, but is weaker and rarely lasts more than about a minute.

It is a twisting column of warmed air scooting across sun-heated ground, made visible by the dust that it lofts upwards. Although usually benign, occasionally dust devils can kill.

Dust devils have been known to appear on Mars since the 1970s. They have been observed both from the ground and from orbit.

The more dust in the Martian atmosphere, the warmer and more agitated it becomes, and this can escalate into a global dust storm.

When the dust settles, it can coat and disable the solar panels that are essential for many of the instruments we’ve landed on the planet.

There’s a lot we don’t know about how these devils function. But new research, published this week in Nature Communications, has recorded what dust devils sound like – giving fresh insights into how they operate.

But it also raises questions about how future astronauts would detect and interpret sounds on the red planet.

There has been a vast amount of erosion on Mars since the last rivers and lakes vanished, including at the landing sites of both Nasa’s current rovers Curiosity and Perseverance.

Although the erosive power of an individual dust devil is tiny, a billion years worth of dust devils could potentially have worn away kilometres of rock.

There are thus many reasons for wanting to better understand how dust devils function.

And we now know what a Martian dust devil sounds like thanks to the new study led by Naomi Murdoch of Toulouse University in France.

Many passing dust devils have been imaged by cameras on Mars landers and rovers, but Murdoch and her team report a dust devil that luckily passed exactly over the Perseverance rover on September 27, 2021, which was on the floor of Jezero crater.

The rover’s masthead camera, named SuperCam, includes a microphone, and this recorded the sound of the wind rising and falling as the dust devil passed over.

In detail, the wind noise rose when the leading wall of the vortex arrived, followed by a lull representing the calm air in the eye of the vortex, before a second episode of wind noise as the trailing wall of the vortex passed over.

This took less than ten seconds, and you can hear the sound recording here(https://jirafeau.isae-supaero.fr/f.php?h=2JWSkdJR&p=1) (turn your volume to max). Other sensors gave information too. They showed that the pressure fell to a minimum between the two bursts of wind noise – which to me is consistent with sucking rather than blowing – and also recorded impacts of individual dust grains onto the rover.

The dust devil was about 25 metres in diameter, at least 118 metres tall, and was tracking across the ground at about five metres per second.

The maximum wind speed in the rotating vortex was probably just under 11 metres per second, equating to a “fresh” to “strong” breeze on Earth.

Did it really sound like that? Listening to a recording purporting to be the sound of Martian wind is all very well, but is this really what we would hear if we were there ourselves? The first thing to note is that this does genuinely originate as “real sound”, unlike other data such as images or radio signals turned into sound (a process known as sonification), such as the so-called sound of two black holes colliding or radio noise from from Venus’s atmosphere.

The dust devil audio file contains actual sound waves picked up by a microphone on Mars.

There the atmosphere is much thinner than on Earth (Martian surface pressure is less than a hundredth of ours), so the high frequency component of sound hardly carries (scientists say it’s “attenuated”).

The result is that the wind sounds much lower in pitch than a similar wind on Earth.

The only other planetary body from which we have genuine sound recordings is Venus, where in 1982 two Soviet “Venera” landers recorded wind and lander operation noises.

However, if you were on Mars you could never hear the wind directly with your own ears.

If you were foolish enough to expose your ears to Mars’s atmosphere, the low external pressure would cause your eardrums to burst, and you would be instantly deaf as well as having no air to breathe.

If you were to go outside in a pressurised spacesuit (a much more sensible idea), what you would hear would depend on how well the sound waves were transmitted through the solid shell of your helmet, and then on how these were turned back into sound waves in the air inside your helmet.

In other words, you would hear a distorted version of what an external microphone would pick up. Imagine walking round on Earth with your head inside a goldfish bowl and you’ll get part of the idea.

If future human explorers on Mars want to hear what’s going on in the external environment, I suspect they will rely on a suit-mounted microphone feeding to wireless ear buds, although I can’t find any evidence that that this has yet been factored into Mars suit design.

This all boils down to a recording from external microphone being the best way to represent sounds on Mars, or indeed any other planet that has an atmosphere.

If you want to hear some more sounds from Mars, NASA has a collection of audio recordings you can listen to.


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Supernova Remnant G278.94+1.35 is Closer to Earth, Claims New Study

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Supernova Remnant G278.94+1.35 is Closer to Earth, Claims New Study

A significant discovery involving a supernova remnant in the Milky Way, identified as G278.94+1.35, has been made by a team of international astronomers. This structure, resulting from a massive stellar explosion, was initially thought to be approximately 8,800 light years away. New findings have revised this distance to about 3,300 light years, making it closer than previously calculated. The remnant’s estimated physical dimensions have also been adjusted to around 189 by 182 light years, contrary to earlier assessments of over 500 light years.

Insights from the Study

According to the study published December 30 on the pre-print server arXiv, highlighted the properties of this remnant. The research team, led by Miroslav D. Filipović, Professor at Western Sydney University, observations were conducted using the Australian Square Kilometer Array Pathfinder (ASKAP) as part of the ASKAP-Evolutionary Map of the Universe project. These observations revealed the nearly circular shape and expansive nature of the remnant, now named “Diprotodon,” in homage to an extinct giant marsupial native to Australia.

The research team attributed the name to raise awareness about the prehistoric megafauna of Australia and ongoing extinction challenges. The findings, as reported by phys.org indicate that the supernova remnant is in a radiative evolutionary phase, suggesting continued expansion.

Characteristics and Significance

Diprotodon’s progenitor star is estimated to have been about 15 times the mass of the Sun. The kinetic energy released during the explosion is approximated at 500 quindecillion ergs. The spectral index of the remnant, measured at around -0.55, aligns with typical shell-type remnants observed in the galaxy. These characteristics place it among the largest supernova remnants known, providing valuable insights into the dynamics of such structures.

The study has offered critical data regarding the formation, expansion, and current state of Diprotodon, contributing to the broader understanding of supernova remnants within the Milky Way.

Catch the latest from the Consumer Electronics Show on Gadgets 360, at our CES 2025 hub.


PFAS Chemicals Harm Freshwater Turtles in Australia, New Research Finds



NISAR Satellite by NASA and ISRO to Monitor Earth Like Never Before

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NISAR: NASA & ISRO’s joint satellite to monitor Earth like never before

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NISAR: NASA & ISRO’s joint satellite to monitor Earth like never before

A collaboration between NASA and the Indian Space Research Organisation (ISRO) has resulted in the NISAR (NASA-ISRO Synthetic Aperture Radar) satellite, which is set to launch in a few months. This mission, designed to track and monitor Earth’s dynamic surface, will use synthetic aperture radar technology to measure changes in land and ice formations. Capable of delivering precise data down to centimetre-level accuracy, NISAR will contribute significantly to understanding natural disasters, ice-sheet movements, and global vegetation shifts.

Unique Dual-Band Technology

According to an official press release by NASA, NISAR is equipped with two radar systems: the L-band with a wavelength of 25 centimetres and the S-band with a 10-centimetre wavelength. This dual-band configuration enables detailed observations of various features, from small surface elements to larger structures. These advanced radars will collect data frequently, covering nearly all land and ice surfaces to provide a comprehensive view of Earth’s transformations.

Technology and Data Applications

As per reports, synthetic aperture radar technology, first utilised by NASA in the 1970s, has been refined for this mission. The data from NISAR will support ecosystem research, cryosphere studies, and disaster response initiatives. Stored and processed in the cloud, the data will be freely accessible to researchers, governments, and disaster management agencies.

Collaboration Between NASA and ISRO

The partnership between NASA and ISRO, formalised in 2014, brought together teams to create this dual-band radar satellite. Hardware was developed across continents, with final assembly in India. ISRO’s Space Applications Centre developed the S-band radar, while NASA’s Jet Propulsion Laboratory provided the L-band radar and other key components. The satellite will launch from ISRO’s Satish Dhawan Space Centre and will be operated by ISRO’s Telemetry Tracking and Command Network.

NISAR’s deployment highlights international collaboration in addressing global challenges, promising transformative insights into Earth’s changing landscapes.

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Velvet Ants Venom Affect Mammals and Insects Differently

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Velvet Ants Venom Affect Mammals and Insects Differently

Velvet ants, despite their name, are not ants but parasitic wasps known for their painful stings. These insects, often called “cow killers” due to the intensity of their sting, possess a potent venom capable of acting on different molecular targets depending on the species they encounter. Their defensive mechanisms, which include venom, warning colours, tough exoskeletons, and unique sounds when threatened, have made them nearly invincible to predators. This versatility has intrigued researchers studying their venom’s effects on various creatures.

Study Highlights Dual Mechanisms in Velvet Ant Venom

According to a study published in Current Biology, velvet ant venom operates differently across species. Researchers, including Lydia Borjon, a sensory neurobiologist at Indiana University Bloomington, found that distinct peptides in the venom affect mammals and insects in unique ways. Experiments conducted on the venom of the scarlet velvet ant (Dasymutilla occidentalis) revealed that specific peptides target sensory neurons differently in insects and mammals.

As reported in Science News, in insects, a peptide called Do6a specifically activates neurons sensitive to harmful stimuli. However, in mammals such as mice, pain is triggered by two less abundant peptides, Do10a and Do13a. These peptides activate a broad range of sensory neurons, inducing a generalised pain response. The findings suggest that velvet ants’ venom tailors its effects based on the biology of the recipient, showcasing a rare example of multi-target venom.

Broader Implications of the Research

Joseph Wilson, an evolutionary ecologist at Utah State University, noted to Science News, that velvet ants’ extensive defensive arsenal could be linked to evolutionary pressures from unknown predators, particularly insects. He suggested that while their venom effectively deters a wide range of species, its evolution might have been influenced by specific ecological interactions. Sam Robinson, a toxinologist at the University of Queensland, highlighted that this type of broad-spectrum venom, though rare, may not be unique, as most venoms are tested on limited species.

The study provides new insights into venom evolution and raises questions about the ecological factors driving the development of such complex defensive strategies.

https://www.gadgets360.com/science/news/nasa-delays-artemis-2-and-artemis-3-missions-to-address-key-technical-challenges-7321848

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