Ricostruzione del nucleo grazie ai dati di insight.
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E misurazione della variazione della rotazione, dovuta agli effetti dello sballottamento del nucleo liquido.
Nell’articolo hanno sbagliato l’unità di misura però, 4 milliarcseconds per year non vuole dire niente, al denominatore ci deve essere il tempo al quadrato.
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Ti leggono. Hanno corretto
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InSight ripreso a inizio aprile da MRO mentre viene lentamente “inghiottito” dalla sabbia marziana. 
L’osservazione della velocità con cui sta venendo ricoperto è utile alla comprensione degli effetti dei venti marziani.
We take these follow up images of InSight to estimate how quickly dust accumulates here. This helps scientists understand how young other surface disturbances like fresh impact craters might be too. […] The study of the aeolian process is one of the HiRISE instrument’s major science themes. Image after image shows dunes, ripples, wind streaks, dust devil tracks, and other features created by the winds. The HiRISE imaging project gives a “wide-angle” view of aeolian effects on the Red Planet and how its various surface units change over time.
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Basandosi sui dati raccolti da InSight alcuni ricercatori ipotizzano che esista una enorme riserva di acqua sotto la crosta di Marte, a 10 - 20 Km di profondità. L’acqua basterebbe a coprire l’intera superficie di Marte creando un oceano di 1-2 Km di profondità.
The data from NASA’s Insight lander allowed the scientists to estimate that the amount of groundwater could cover the entire planet to a depth of between 1 and 2 kilometers, or about a mile. […] It’s located in tiny cracks and pores in rock in the middle of the Martian crust, between 11.5 and 20 kilometers (7 to 13 miles) below the surface.
L’articolo da UC Berkeley.
We use rock physics models and Bayesian inversion to identify combinations of lithology, liquid water saturation, porosity, and pore shape consistent with the constrained mid-crust (∼11.5 to 20 km depths) seismic velocities and gravity near the InSight lander. A mid-crust composed of fractured igneous rocks saturated with liquid water best explains the existing data.
Il paper della ricerca:
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InSight ripreso il 23 ottobre, sempre da MRO.
HiRISE caught a glimpse of the NASA’s retired InSight lander, documenting the accumulation of dust on the spacecraft’s solar panels. In this image taken on 23 October 2024, InSight’s solar panels have acquired the same reddish-brown hue as the rest of the planet.
Edit 20/12.
Articolo del JPL. Non sapevo - o non ricordavo! - che la NASA fosse ancora in ascolto in attesa di ricevere un segnale da InSight.
[…] engineers continued listening for radio signals from the lander in case wind cleared enough dust from the spacecraft’s solar panels for its batteries to recharge. Having detected no changes over the past two years, NASA will stop listening for InSight at the end of this year.
Nella pagina c’è un video (di qualità molto migliore) con le immagini di InSight raccolte da MRO.
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Non direi che stia venendo inghiottito, mi sembra sostanzialmente nelle condizioni precedenti, anche la copertura di polvere sarà aumentata ma già anni fa la sonda era diventata marrone. Perché venga inghiottito ci vorranno migliaia di anni
Una ricerca ha provato a spiegare le cause dell’indurimento dello strato superficiale del suolo marziano che ha impedito alla “talpa” di InSight di scavare oltre i 40cm di profondità.
We measured the temperature in the soil during several Martian days and over a Martian year using the NASA InSight Mars mission’s Heat Flow and Physical Properties Package. The average temperature was −56°C (217.5 K) over the depth extent of the thermal probe, which was about 40 cm. The temperature varied by 5–7° during the day, which is only a tenth of the daily surface temperature variation. It varied by 13° during the seasons. The temperature is subfreezing for water, but it allows the formation of thin films of salty brine for 10 hr or more during a Martian day. The solidification of the brine is a likely explanation for the observed few tens of centimeters thick duricrust, a layer of consolidated, cohesive sand, which is thought to have hampered the penetration to greater depth of the mission’s thermal probe.
Il riassunto pubblicato sul sito del DLR.
Il paper della ricerca:
Mars Soil Temperature and Thermal Properties From InSight HP³ Data
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Un nuovo studio realizzato utilizzando i dati di InSight è stato pubblicato su Science. I resti di enormi impatti con asteroidi sono ancora presenti sotto la superficie di Marte.
Il paper:
Seismic evidence for a highly heterogeneous martian mantle
Il comunicato della NASA:
What appear to be fragments from the aftermath of massive impacts on Mars that occurred 4.5 billion years ago have been detected deep below the planet’s surface. […]
Turning back the clock, they concluded that the lumps likely arrived as giant asteroids or other rocky material that struck Mars during the early solar system, generating those oceans of magma as they drove deep into the mantle, bringing with them fragments of crust and mantle.
Charalambous likens the pattern to shattered glass — a few large shards with many smaller fragments. The pattern is consistent with a large release of energy that scattered many fragments of material throughout the mantle. It also fits well with current thinking that in the early solar system, asteroids and other planetary bodies regularly bombarded the young planets.
Un articolo da Science Magazine:
For decades, planetary scientists have envisioned rocky planets such as Earth and Mars as possessing distinct, ordered layers—crust, mantle, and core—stacked like the layers of a delicate millionaire’s shortbread. However, seismological insights from NASA’s InSight mission tell a dramatically different story for Mars. Using seismic data collected on the Martian surface, researchers found that the planet’s mantle is far from uniform; it is composed of discrete, compositionally distinct fragments that range in size, with some reaching up to four kilometers across. This patchwork of ancient material provides a rare geological window into the planet’s primordial past.
Seismic data from InSight plays a pivotal role in these revelations. The lander recorded eight particularly clear “marsquake” events, two triggered by recent meteorite impacts forming relatively small craters approximately 150 meters wide. High-frequency seismic waves from these quakes exhibited delays and scattering phenomena inconsistent with a homogeneous mantle. Instead, wave interference patterns indicated a mantle riddled with varying compositional domains—some large and persistent, others smaller and more dispersed.
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