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Volcanoes-Sapas_Mons-00.jpgMagellan Probe: radio image of Sapas Mons Volcano (false color)118 visiteLa risposta a questa domanda, ovviamente, potremmo non averla mai.
Un ultimo dato suggestivo attiene il campo gravitazionale di Venere il quale - completamente diverso da quello terrestre - potrebbe essere pesantemente influenzato da processi fisici che avvengono nelle profondità del Pianeta.
Ad ogni modo i processi tettonici globali che caratterizzano Venere sono ancora avvolti nel mistero. Così come avvolta nel mistero è la fine della Sonda Magellano.
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Volcanoes-Sapas_Mons-01.jpgMagellan Probe: radio image of Sapas Mons Volcano109 visiteIl 12 Ottobre 1994, infatti, dopo 4 anni di orbite, di preziose osservazioni e di raccolta dati relativi al Pianeta, il contatto radio con la Terra si interrompeva bruscamente e, neppure 24 ore dopo, il Centro Controllo Missione dichiarava la (presunta) perdita definitiva della Navicella.
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Volcanoes-Sapas_Mons-02.jpgMagellan Probe: radio image of Sapas Mons Volcano (detail)138 visiteUna così rapida decisione di considerare persa la Sonda può lasciare sorpresi (basti pensare agli innumerevoli tentativi compiuti dai Tecnici NASA di ripristinare i contatti radio, per esempio, con il Mars Polar Lander oppure con la Sonda ESA "Beagle", prima di dichiarare la perdita delle Navicelle) e che cosa sia effettivamente accaduto a Magellano non lo sa nessuno, ma non è da escludere, tuttavia, che la rapidità adottata nel prendere questa decisione sia stata determinata, fra l'altro, in ragione dell'avvenuto conseguimento della (quasi) totalità degli scopi della Missione.
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Volcanoes-Sapas_Mons-03.jpgMagellan Probe: radio image of Sapas Mons Volcano Area127 visiteInoltre - e per rendersi conto di questo dato basta verificare i documenti relativi all'operato della Sonda magellano - è fortemente probabile che la perdita del contatto radio sia stata causata dalla semplice e naturale consunzione della Navicella, costretta (per 4 anni) al lavoro in condizioni alquanto ostili.
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Volcanoes-Sapas_Mons-PIA00099-PCF-LXTT-IPF.jpgThe Eastern Flank of Sapas Mons (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)79 visiteThis NASA - Magellan Spacecraft's image - centered near 9,6° North Latitude and 189,5° East Longitude - covers an area of approx. 140 Km (such as about 86,94 miles) by approx. 110 Km (such as aabout 68,31 miles) and shows us part of the Eastern Flank of the Venusian Volcano known as Sapas Mons, which is located on the Western Edge of Atla Regio.
The bright Lobate Surface Features visible along the Southern and Western portions of the image, oriented in a North/East to South/West directions, are huge Lava Flows. These Flows range, in width, from approx. 5 to 25 Km (such as from about 3,1 to 15,525 miles), with lengths going from about 50 to approx. 100 Km (such as from about 31,05 to 62,1 miles), and they seem to extend themselves way off the area shown here. Additional Radar-Dark (---> Smooth) Flows are also present. The Radar-Bright Linear Structures found in the North/Western portion of the frame are interpreted to be (relatively) shallow Faults and Fractures, which could possibly be associated with the emplacement of Magma in the Sub-Surface.
Furthermore, located near the center of the image, there is an Impact Crater whose diameter is roughly 20 Km (such as about 12,42 miles). This Impact Crater is superimposed on a North/East-to-South/West trending Fracture, while the Southern Side of the Crater's Ejecta Blanket is covered by an approx. 6 Km (such as about 3,72 miles) wide Radar-Bright Lava Flow. These (just apparently) complicated relations indicate that the Crater post-dates an episode of Fracturing and that is older than the Lava Flows covering its Southern Edge.
Last, but not least, this is one of only a few places on Venus where an Impact Crater is seen to be covered by Volcanic Deposits.
This frame (which is an Original NASA - Magellan Spacecraft Radio-Image-Mosaic published on the NASA - Planetary Photojournal with the n. PIA 00099), since it is just a Radio-Image of the Venusian Surface and NOT a real view of it, has been colorized, according to an educated guess carried out by Dr Paolo C. Fienga (LXTT-IPF), in what they could reasonably be its possible Absolute Natural Colors (such as the colors that a human eye would perceive if someone were onboard the NASA - Magellan Spacecraft and, once the thick layer of Venusian Clouds and Fogs is completely overcome, looked down, towards the Surface of Venus itself), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.MareKromium
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Z-Venus~1.jpgIs there Life on Venus?108 visitePotential signs of life on Venus are fading as astronomers downgrade their original claims.
"The announcement in September 2020 took the World by storm: Researchers using two radio telescopes found signs that the clouds of Venus were harboring phosphine, a toxic compound that on Earth is only made in significant quantities by microbes and chemists. The unexpectedly high levels detected on Venus could point to a floating microbial biosphere, the researchers suggested in a paper published in Nature Astronomy. But almost immediately, other astronomers began to criticize the results, with four independent studies pointing out questionable methods or failing to reproduce the results.
Now, after reanalyzing their data, the original proponents are downgrading their claims. Even the most favorable interpretation of their data now suggests phosphine levels are at least seven times lower than first reported, making it a much more tentative finding, the authors reported in a preprint posted on 17 November to arXiv. But the team still believes the gas is there, with the possibility that local pockets rise to higher levels, said Jane Greaves, an astronomer at Cardiff University who led the work, in a talk today to NASA’s Venus Exploration Analysis Group (VEXAG). “We have again a phosphine line.”
Lets hope more research and study provide the necessary data to prove one way or another!".MareKromium
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