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before_the_storm_1600.jpgBefore the Storm...124 visite
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The_Moon-EB-MF-LXTT-IPF.jpgMoon-Rising (by Elisabetta Bonora and Marco Faccin/LXTT/IPF)124 visite"...It takes an instant to erase a Life; but it takes a Lifetime to erase an instant..."
Jim MorrisonMareKromium
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Voyager_1A.jpgFarewell...123 visiteOn April 17, 2'26, engineers at NASA’s Jet Propulsion Laboratory (JPL) in Southern California sent commands to shut down an instrument aboard Voyager 1 called the Low-energy Charged Particles experiment, or LECP. The nuclear-powered spacecraft is running low on power, and turning off the LECP is considered the best way to keep humanity’s first interstellar explorer going.
The LECP has been operating almost without interruption since Voyager 1 launched in 1977 — almost 49 years. It measures low-energy charged particles, including ions, electrons, and cosmic rays originating from our solar system and galaxy. The instrument has provided critical data about the structure of the interstellar medium, detecting pressure fronts and regions of varying particle density in the space beyond our heliosphere. The twin Voyagers are the only spacecraft that are far enough from Earth to provide this information.
Like Voyager 2, Voyager 1 relies on a radioisotope thermoelectric generator, a device that converts heat from decaying plutonium into electricity. Both probes lose about 4 watts of power each year. After almost a half-century in space, power margins have grown razor thin, requiring the team to conserve energy by shutting off heaters and instruments while making sure the spacecraft don’t get so cold that their fuel lines freeze.
During a routine, planned roll maneuver on Feb. 27, Voyager 1’s power levels fell unexpectedly. Mission engineers knew any additional drop in power could trigger the spacecraft’s undervoltage fault protection system, which would shut down components on its own to safeguard the probe, requiring recovery by the flight team — a lengthy process that carries its own risks.
The Voyager team needed to act first.
“While shutting down a science instrument is not anybody’s preference, it is the best option available,” said Kareem Badaruddin, Voyager mission manager at JPL. “Voyager 1 still has two remaining operating science instruments — one that listens to plasma waves and one that measures magnetic fields. They are still working great, sending back data from a region of space no other human-made craft has ever explored. The team remains focused on keeping both Voyagers going for as long as possible.”
Far-out plan
The choice of which instrument to turn off next wasn’t made in the heat of the moment. Years ago, the Voyager science and engineering teams sat down together and agreed on the order in which they would shut off parts of the spacecraft while ensuring the mission can continue to conduct its unique science. Of the 10 identical sets of instruments that each spacecraft carries, seven have been shut off so far. For Voyager 1, the LECP was next on that list. The team shut off the LECP on Voyager 2 in March 2025.
Because Voyager 1 is more than 15 billion miles (25 billion kilometers) from Earth, the sequence of commands to shut down the instrument will take 23 or so hours to reach the spacecraft, and the shutdown process itself will take about three hours and 15 minutes to complete. One part of the LECP — a small motor that spins the sensor in a circle to scan in all directions — will remain on. It uses little power (0.5 watts), and keeping it running gives the team the best chance of being able to turn the instrument back on someday if they find extra power.
What comes next
Engineers are confident that shutting down the LECP will give Voyager 1 about a year of breathing room. They are using the time to finalize a more ambitious energy-saving fix for both Voyagers they call “the Big Bang,” which is designed to further extend Voyager operations. The idea is to swap out a group of powered devices all at once — hence the nickname — turning some things off and replacing them with lower-power alternatives to keep the spacecraft warm enough to continue gathering science data.
The team will implement the Big Bang on Voyager 2 first, which has a little more power to spare and is closer to Earth, making it the safer test subject. Tests are planned for May and June 2026. If they go well, the team will attempt the same fix on Voyager 1 no sooner than July. If it works, there is even a chance that Voyager 1’s LECP could be switched back on.MareKromium
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Sunrises.jpgPoints of View...122 visitenessun commentoMareKromium
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FireRainbow_Harbig_960.jpgNice...122 visite“La Guerra di Religione: in pratica vi siete uccisi, vi state uccidendo e vi ucciderete per decidere chi abbia l'Amico Immaginario migliore"
Richard JeniMareKromium
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CollidingGalaxies-PIA02180_modest.jpgHearts of Glass121 visiteThis artist's concept shows delicate greenish crystals sprinkled throughout the violent core of a pair of colliding galaxies. The white spots represent a thriving population of stars of all sizes and ages. NASA's Spitzer Space Telescope detected more than 20 bright and dusty galactic mergers like the one depicted here, all teeming with the tiny gem-like crystals.
When galaxies collide, they trigger the birth of large numbers of massive stars. Astronomers believe these blazing hot stars act like furnaces to produce silicate crystals in the same way that glass is made from sand. The stars probably shed the crystals as they age, and as they blow apart in supernovae explosions.
At the same time the crystals are being churned out, they are also being destroyed. Fast-moving particles from supernova blasts easily convert silicates crystals back to their amorphous, or shapeless, form.
How is Spitzer seeing the crystals if they are rapidly disappearing? Astronomers say that, for a short period of time at the beginning of galactic mergers, massive stars might be producing silicate crystals faster than they are eliminating them. When our own galaxy merges with the Andromeda galaxy in a few billion years, a similar burst of massive stars and silicate crystals might occur.
Crystal Storm in Distant Galaxy
The graph (see inset above) of infrared data from NASA's Spitzer Space Telescope tells astronomers that a distant galaxy called IRAS 08752+3915 is experiencing a storm of tiny crystals made up of silicates. The crystals are similar to the glass-like grains of sand found on Earth's many beaches.
The data were taken by Spitzer's infrared spectrograph, which splits light open to reveal its rainbow-like components. The resulting spectrum shown here reveals the signatures of both crystalline (green) and non-crystalline (brown) silicates.
Spitzer detected the same crystals in 20 additional galaxies, all belonging to a class called ultraluminous infrared galaxies. These extremely bright and dusty galaxies usually consist of two galaxies in the process of smashing into each other. Astronomers believe massive stars at the hearts of the galaxies are churning out clouds of silicate crystals. This phenomenon may represent a short-lived phase in the evolution of galactic mergers.
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ALANBEAN-CORETUBE.jpgCore-Tube120 visiteDalla Galleria Pittorica dell'Astronauta Alan Laverne Bean: un Omaggio alla Luna ed a quei pochi che ebbero il coraggio, la fortuna ed il privilegio di camminarci sopra.
Ma lasciamo che sia "Alan" a raccontarci questa storia: la "Sua Storia"...
"...When my book, "Apollo, An Eyewitness Account", was published in October of 1998, I felt an overall sense of satisfaction. I was, in fact, preserving some of my special memories of the Apollo Program. This was the reason I resigned from NASA to become an artist.
I was moving right along but I noticed my goals for the future were even more ambitious. I wanted to paint the Moon more beautifully than I had done so far, as colorful as it could be painted, and still look like the Moon to me, a worthy but elusive goal.
I stopped painting commissions and began painting several series of studies to explore and develop new color techniques and combinations. This intense and dedicated effort consumed me for the better part of a year with the resulting changes first coming to full fruition in this painting.
Sometimes when I look at this painting I wonder if the changes were all that much. I question if anyone other than me can see them or even care? I don't know. Was it worth the time? I hope so...".
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Supernova.jpgSupernova (a Fantasy - by Dr Paolo C. Fienga - based on an Alex Cherney's picture)119 visiteChe cosa accadrebbe e, soprattutto, che cosa vedremmo se una stelle di grandi dimensioni esplodesse e, dal nostro punto di vista, si trovasse nei pressi del "Centro" della Via Lattea?
Probabilmente assisteremmo ad uno spettacolo quale è quello che vedete qui, in questo splendido frame di Alex Cherney (rappresentativo di una "Visione Galattica" ottenuta dall'Australia - Loch Ard Gorge), da me liberamente - ma solo in piccola parte - modificato.
Una sorta di "Piccolo Sole" illuminerebbe (in maniera maestosa!) la notte, forse per una settimana o poco più, ma senza trasformarla in giorno o in crepuscolo.
Si, sarebbe un Grande Spettacolo...Davvero.MareKromium
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Fractal_Tree.jpgFractal Tree (by Dr Gianluigi Barca)119 visitenessun commentoMareKromium
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Upsilon_Andromedae.jpgUpsilon Andromedae119 visiteVivamus mea Lesbia, atque amemus,
Rumoresque senum severiorum
Omnes unius aestimemus assis!
Soles occidere et redire possunt:
Nobis cum semel occidit brevis lux,
Nox est perpetua una dormienda.
Da mi basia mille, deinde centum,
Dein mille altera, dein secunda centum,
Deinde usque altera mille, deinde centum.
Dein, cum milia multa fecerimus,
Conturbabimus illa, ne sciamus,
Aut ne quis malus invidere possit,
Cum tantum sciat esse basiorum.
G. V. CatulloMareKromium
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The_Lion_Sleeps_Tonight.jpgA-Weema-Weh!119 visite"...Simba inaweza kubadilika Dunia...".
Kujitolea kwa Afrika.
MareKromium
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Freedom.jpgFreedom (credits: Dr Marco Faccin)118 visite"...Un Regno che non conosce la Pietà, è un Regno effimero..."MareKromium
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