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M-017-0.jpgM 17 - The "Omega Nebula"61 visite"...Una differenza tra Scienza e Fantascienza? Io direi che mentre la Scienza è la disciplina della certezza, la Fantascienza è la disciplina del dubbio..."
(anonimo)MareKromium
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PSP_003252_1425_RED_browse-01.jpgBright Gully Deposit in Terra Sirenum (the "crater" - close-up; false colors)61 visiteAs seen in the context image and here, the appearance of the crater wall differs between the Northern and Southern Sides. On the Northern Pole-Facing Side Walls, prominent gullies with channels and aprons are apparent, with many of these having valley-like alcoves near their tops. The morphology of the gullies is consistent with formation by a fluid, most likely water.
On the pole-facing slopes, ground ice or aquifers may be more stable, being subjected to less heating from sunlight compared to equator-facing slopes.
In contrast, the Southern, Equator-Facing Walls are dominated by rocky debris flows that lack prominent channels.MareKromium
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Mira-PIA09958-0.jpgMira soars through the Sky!61 visiteNew ultraviolet images from NASA's Galaxy Evolution Explorer shows a speeding star that is leaving an enormous trail of "seeds" for new solar systems. The star, named Mira (pronounced my-rah) after the latin word for "wonderful," is shedding material that will be recycled into new stars, planets and possibly even life as it hurls through our galaxy.
In figure 1, the upper panel shows Mira's full, comet-like tail as seen only in shorter, or "far" ultraviolet wavelengths, while the lower panel is a combined view showing both far and longer, or "near" ultraviolet wavelengths. The close-up picture at bottom gives a better look at Mira itself, which appears as a pinkish dot, and is moving from left to right in this view. Shed material appears in light blue. The dots in the picture are stars and distant galaxies. The large blue dot on the left side of the upper panel, and the large yellow dot in the lower panel, are both stars that are closer to us than Mira.
The Galaxy Evolution Explorer discovered the strange tail during part of its routine survey of the entire sky at ultraviolet wavelengths. When astronomers first saw the picture, they were shocked because Mira has been studied for over 400 years yet nothing like this has ever been documented before.
Mira's comet-like tail stretches a startling 13 light-years across the sky. For comparison, the nearest star to our sun, Proxima Centauri, is only about 4 light-years away. Mira's tail also tells a tale of its history -- the material making it up has been slowly blown off over time, with the oldest material at the end of the tail being released about 30,000 years ago (figure 2).
Mira is a highly evolved, "red giant" star near the end of its life. Technically, it is called an asymptotic giant branch star. It is red in color and bloated; for example, if a red giant were to replace our sun, it would engulf everything out to the orbit of Mars. Our sun will mature into a red giant in about 5 billion years.
Like other red giants, Mira will lose a large fraction of its mass in the form of gas and dust. In fact, Mira ejects the equivalent of the Earth's mass every 10 years. It has released enough material over the past 30,000 years to seed at least 3,000 Earth-sized planets or 9 Jupiter-sized ones.
While most stars travel along together around the disk of our Milky Way, Mira is charging through it. Because Mira is not moving with the "pack," it is moving much faster relative to the ambient gas in our section of the Milky Way. It is zipping along at 130 kilometers per second, or 291,000 miles per hour, relative to this gas.
Mira's breakneck speed together with its outflow of material are responsible for its unique glowing tail. Images from the Galaxy Evolution Explorer show a large build-up of gas, or bow shock, in front of the star, similar to water piling up in front of a speeding boat. Scientists now know that hot gas in this bow shock mixes with the cooler, hydrogen gas being shed from Mira, causing it to heat up as it swirls back into a turbulent wake. As the hydrogen gas loses energy, it fluoresces with ultraviolet light, which the Galaxy Evolution Explorer can detect.
Mira, also known as Mira A, is not alone in its travels through space. It has a distant companion star called Mira B that is thought to be the burnt-out, dead core of a star, called a white dwarf. Mira A and B circle around each other slowly, making one orbit about every 500 years. Astronomers believe that Mira B has no effect on Mira's tail.
Mira is also what's called a pulsating variable star. It dims and brightens by a factor of 1,500 every 332 days, and will become bright enough to see with the naked eye in mid-November 2007. Because it was the first variable star with a regular period ever discovered, other stars of this type are often referred to as "Miras."
Mira is located 350 light-years from Earth in the constellation Cetus, otherwise known as the whale. Coincidentally, Mira and its "whale of a tail" can be found in the tail of the whale constellation.
These images were between November 18 and December 15, 2006.
MareKromium
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as16-107-17441.jpgAS 16-107-17441 - Cosmic Ray Experiment (additional processing by Lunexit)61 visiteCaption NASA:"143:15:05 MT - Cross-Sun of the Cosmic Ray Experiment, which is sitting in the Minus-Y Footpad. The fuel cask is beyond the strut on the side of the Descent Stage and the dome and Dome Removal Tool is under the LM farther back".MareKromium
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as14-66-09320-01.jpgAS 14-66-9320 (2) - Blue Flare (nature undetermined)61 visiteUn esempio ulteriore di extra-stretch della Blue Flare che appare nel frame AS 14/9320: come vedete la texture della Blue Flare resta limpida e ben definita (un indice di "genuinità" della possibile Anomalìa), ma il "cuore" (la "sfera bianca" da cui si irradia l'illuminazione blu) NON si vede (e questo è un indice di NON genuinità della possibile Anomalìa).
Per rispondere a tanti Amici che ci hanno scritto al riguardo (citiamo fra tutti il bravissimo Titanio44) vorremmo dire che l'idea di definire la Blue Flare come un qualcosa di "certamente alieno" (alieno ----> da "estraneo" e non "man-made" per giungere sino a "evidenza di intelligenza extra-terrestre) è, ovviamente, un azzardo; tuttavia qualificare la Blue Flare - come hanno fatto in tanti, specie in alcuni Forum USA che abbiamo individuato grazie ad un Socio Americano che ci segue da tempo, nei termini di "easy and obvious image artifact (i.e.: lens flare)" è, a nostro avviso, un azzardo ancora più grande, nonchè un peccatuccio di over-semplificazione. La Blue Flare, che si creda o meno alla sua matrice non terrestre, è ancora oggi un mistero; studiarla e cercare di capire sino a che punto essa è un "corpo reale" e sino a che punto essa è invece una "illusione" è il compito dei Ricercatori Pragmatici ed Open-Minded.
"Bollare" la Blue Flare, invece e visti i dati in nostro possesso, sia come Alien Probe, sia come Lens Flare, vuol dire commettere una leggerezza enorme e, in ambo i casi, giungere ad una conclusione radicale pur trovandosi in difetto di elementi sufficienti.
Pensateci sopra e scriveteci!MareKromium
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PSP_004847_1745-WFull2.jpgThe "Martian Black Hole" (general context frame - False Colors; elab. Lunexit)61 visiteCon questa ricostruzione in colori "naturali" della Regione su cui si trova il nostro "Black Hole", forse riusciamo a rispondere (finalmente con chiarezza) a qualche Lettore il quale ci chiedeva come mai, a fronte di frames che inquadrano la stessa Regione Marziana, spesso le colorizzazioni che facciamo sono diverse. Ebbene la risposta è in questo frame-composite: la nostra colorizzazione RISENTE SEMPRE e COMUNQUE del tipo di filtro adottato dalla Sonda per effettuare la ripresa (nonchè delle effettive condizioni di illuminazione "locali")! Questo caso è eclatante e chiarificatore: diverse stripes, ottenute con diversi filtri, producono - anche a fronte dell'uso di un processo di colorizzazione omogeneo ed unitario - dei risultati MOLTO diversi (provate con JASC Paint Shop Pro, se volete - funziona egregiamente per le colorizzazioni, e verificate Voi stessi).MareKromium
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NGC-1333-PIA09965.jpgWater Vapor inside NGC 133361 visiteThis plot of infrared data, called a Spectrum, shows the strong signature of water vapor deep within the core of an Embryonic Star System called NGC 1333-IRAS 4B.
The data were captured by NASA's SST using an instrument called Spectrograph.
A spectrograph collects light and sorts it according to color, or wavelength. In this case, infrared light from NGC 1333-IRAS 4B was broken up into the wavelengths listed on the horizontal axis of the plot. The sharp spikes, called spectral lines, occur at wavelengths at which the stellar object is particularly bright. The signature of water vapor is revealed in the pattern of wavelengths at which the spikes appear.
By comparing the observed data to a model (lower curve), astronomers can also determine the physical and chemical details of the region.
F.e.: Astronomers say these data suggest that ice in a cocoon surrounding the forming star is falling inward. The ice then smacks supersonically into a dusty planet-forming disk surrounding the stellar embryo, heats up and vaporizes quickly, releasing the infrared light that Spitzer collected.
MareKromium
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SouthPolarEclipse.jpgLunar Eclipse from the South Pole61 visiteCaption NASA:"The Moon was up continuously for 14 days in August -- when viewed from the South Pole. But during the total Lunar Eclipse on August 28, it circled only about 10° above the horizon. For Robert Scharwz, the resulting long line-of-sight through the atmosphere that blurred his images was a minor problem when he recorded this 4-hour long Lunar Eclipse sequence. A more severe problem was the outdoor air temperature of - 68° C (such as - 90 F). The extreme cold required him to make the series of exposures through a slit in a window from inside a heated room. Though the heat produced convection and further blurring, it was the only way to keep the camera at a reasonable operating temperature for an extended period of time. Still, he was rewarded with this impressive record of August's lunar eclipse from a unique perspective on planet Earth".MareKromium
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AS15-88-12004_HR.jpgAS 15-88-12004 - Reflection or In-Transit "UFO"?61 visiteDall'occhio attentissimo del Dr Barca, un nuovo Mistero Lunare: circa ad ore 03:00 del frame, poco al di sopra del bordo della Luna (e sulla Regione di Aristarco ed Erodoto: una Regione famosissima per i Cacciatori di TLP ed altri Fenomeni Lunari Anomali), una luce bianca ed azzurra (che ci mostra anche la caratteristica "sfuocatura da movimento"...) sembra transitare via veloce, tenendosi ad una debita distanza dalla Navicella USA.
Osservate, nel finestrino, i riflessi prismatici causati dal Sole (fuori obbiettivo, ma certo abbastanza prossimo al campo di ripresa per generare degli splendidi image-artifacts), alcuni dettagli - riflessi - dell'interno dell'Astronave e quindi la mano dell'Astronauta che sta fotografando (forse Scott, ma non abbiamo modo di esserne certi).
E la "Luce Blu"? La "Luce Blu", secondo noi, NON è un riflesso di qualcosa che si trova all'interno dell'Astronave, non è un vizio del frame e non è un effetto prismatico. Ed inoltre "scompare" già dal frame successivo. Che cosa stiamo guardando?!?
Complimenti, come sempre, al Dr Gianluigi Barca!!!MareKromium
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The_Sun-Coronal_Hole.jpgCoronal Hole61 visiteCaption NASA:"The dark expanse below the Equator of the Sun is a Coronal Hole, such as a Low Density Region extending above the surface, where the Solar Magnetic Field opens freely into interplanetary space.
Shown in false color, the picture was recorded on September 19th, 2007, in Extreme Ultraviolet Light by the EIT instrument onboard the space-based SOHO observatory. Studied extensively from space since the 1960s in ultraviolet and x-ray light, Coronal Holes are known to be the source of the high-speed Solar Wind, atoms and electrons that flow outward along the open magnetic field lines.
The Solar Wind streaming from this coronal hole triggered colorful auroral displays on planet Earth begining late last week, enjoyed by spaceweather watchers at high latitudes".MareKromium
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Z-109-The_Moon-PlaskettCrater.jpgCrater Plaskett & Companions61 visiteCaption ESA:"Plaskett crater is the bottom crater in this mosaic built with images taken by the Advanced Moon Imaging Experiment (AMIE) on board ESA's SMART-1 spacecraft. Plaskett and its two Companion Craters sit near the Moon’s North Pole.
The shadow lengths can be used to calculate the height of surface features.
Data like this can be turned into virtual simulations of the surface to help engineers design suitable landers. From its rim, the full Earth would graze just above the horizon for only a few days per month. However some areas within the Crater never see the Earth.
Rozhdestvenskiy is a large lunar crater of about 177 Km of diameter at it is centered at 85,2° North and 155,4° West (just above Plaskett).
Its northern rim is just 60 Km from the North Pole".MareKromium
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IC-1396.jpgThe "Elephant's Trunk Nebula" in IC 139661 visite"...Quando c'è da criticare e da sputare sentenze, si è sempre in grande compagnia; quando c'è da creare o difendere qualcosa, si è quasi sempre da soli..."
(antico detto popolare)MareKromium
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