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Earth&Sun-000-sunearth_01G.jpgMagnetic Fields... (1)55 visitenessun commento
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Sun_Shock-Wave.gifThe "Moreton Wave"55 visiteCaption NASA originale:"Tsunamis this large don't happen on Earth. One week ago (Dec. 2006), a large solar flare from an Earth-sized sunspot produced a tsunami-type shock wave that was spectacular even for the Sun. Pictured above, the tsunami wave was captured moving out from active region AR 10930 by the Optical Solar Patrol Network (OSPAN) telescope in New Mexico, USA. The resulting shock wave, known technically as a Moreton Wave, compressed and heated up gasses including Hydrogen in the photosphere of the Sun, causing a momentarily brighter glow.
The above image was taken in a very specific red color emitted exclusively by hydrogen gas. The rampaging tsunami took out some active filaments on the Sun, although many re-established themselves later.
The solar tsunami spread at nearly 1 MKM per hour, and circled the entire Sun in a matter of minutes".MareKromium
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The_Sun-PIA09321.jpgDisk Image of the Sun, March 26, 2007 (Anaglyph)55 visitenessun commentoMareKromium
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SunFlare-prom1743_eit_big.jpgA Twisted Solar Eruptive Prominence55 visiteCaption NASA:"Ten Earths could easily fit in the "claw" of this seemingly solar monster. The monster, though, visible on the lower left, is a huge Eruptive Prominence seen moving out from our Sun. The above dramatic image taken early in the year 2000 by the Sun-orbiting SOHO satellite. This large prominence, though, is significant not only for its size, but its shape. The twisted figure eight shape indicates that a complex magnetic field threads through the emerging solar particles. Differential rotation inside the Sun might help account for the surface explosion.
Although large prominences and energetic Coronal Mass Ejections (CMEs) are relatively rare, they are occurred more frequently near Solar Maximum, the time of peak sunspot and solar activity in the eleven-year Solar Cycle".MareKromium
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Solar_Prominence.jpgSolar Prominence55 visiteCaption NASA, da "NASA - Picture of the Day" del giorno 15 Marzo 2009:"What's happened to our Sun? It was sporting a spectacular -- but not very unusual -- Solar Prominence.
A Solar Prominence is a cloud of solar gas held above the Sun's Surface by the Sun's Magnetic Field. In 2004, NASA's Sun-orbiting SOHO Spacecraft imaged an impressively large prominence hovering over the surface, pictured above.
The Earth would easily fit under the hovering curtain of hot gas.
A quiescent Prominence typically lasts about a month, and may erupt in a Coronal Mass Ejection (CME) expelling hot gas into the Solar System. Although somehow related to the Sun's changing Magnetic Field, the energy mechanism that creates and sustains a Solar Prominence is still a topic of research".MareKromium
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PerihelionAphelion_cervignon800.jpgPerihelion and Aphelion55 visiteDa "NASA - Picture of the Day" del giorno 3 Luglio 2009:"This year Aphelion, the point in Earth's elliptical orbit when it is farthest from the Sun, occurs tomorrow, July 4th.
Of course, that doesn't affect the seasons on our fair Planet, because those are determined by the tilt of Earth's Axis of Rotation and not Earth's distance from the Sun: so July is still Winter in the South and Summer in Northern Hemisphere. But it does mean that on July 4th the Sun will be at its smallest apparent size. This composite neatly compares two pictures of the Sun taken with the same telescope and camera on the dates of Perihelion (closest approach) and Aphelion in 2008.
The image labels include Earth's distance in kilometers from the Sun on the two dates.
Otherwise difficult to notice, the change in the Sun's apparent diameter between Perihelion and Aphelion is clear. The difference amounts to a little over 3%".MareKromium
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Solar_Prominence-STEREO.jpgHuge Solar Prominence55 visiteCaption NASA:"What does a Solar Prominence look like in three dimensions? To help find out, NASA launched the STEREO satellites to keep a steady eye on the Sun from two different vantage points.
The STEREO satellites orbit the Sun nearly along Earth's orbit, but one (dubbed "Ahead" ---> Avanti) currently leads the Earth, while the other (dubbed "Behind" ---> "Dietro") currently trails. Three weeks ago, a powerful Prominence erupted and remained above the Sun for about 30 hours, allowing the STEREO satellites to get numerous views of it from different angles.
Pictured above is a High-Resolution image of the event from the STEREO "Ahead" satellite.
A video of the Prominence erupting as seen from both Spacecrafts can be found at http : // www . youtube . com / watch?v = _RjswBx6ysQ.
The unusually quiet nature of the Sun over the past two years has made large prominences like this relatively rare. The combined perspective of STEREO will help astronomers better understand the mechanisms for the creation and evolution of Prominences, Coronal Mass Ejections, and Solar Flares".
MareKromium
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Solar_Eclipse-2010.jpgMillennium's Annular Solar Eclipse55 visiteDa "NASA - Picture of the Day" del giorno 22 Gennaio 2010:"The Moon's shadow raced across planet Earth on January 15, 2010.
Observers within the central shadow track were able to witness an Annular Solar Eclipse as the Moon's apparent size was too small to completely cover the Sun. A visually dramatic "Ring of Fire", the annular phase lasted up to 11' and 8", depending on location: the longest Annular Solar Eclipse for the next 1000 years.
This picture of the Moon's silhouette just before mid-eclipse was taken within the eclipse path from the city of Kanyakumari at the southern tip of India. The telescopic image was made through a filter that blocks most Visible Light, but still transmits light from Hydrogen Atoms.
As a result, detailed mottling, or granulation, caused by heat convection in the Sun's Atmosphere can be seen around the dark Lunar Disk".MareKromium
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The Sun-P-021-01450.jpgJapanese Sun54 visitenessun commento
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Solar Corona.jpgThe 2006 Total Solar Eclipse: the Solar Corona54 visiteDa "NASA - Picture of the Day", del 7 Aprile 2006:"During a total Solar Eclipse, the Sun's extensive outer atmosphere (or Corona) is an awesome and inspirational sight. The subtle shades and shimmering features of the corona that engage the eye span a brightness range of over 10.000 to 1, making them notoriously difficult to capture in a single picture. But this composite of 33 digital images ranging in exposure time from 1/8000 to 1/5th of second comes very close to revealing the crown of the Sun in all its glory. The telescopic views were recorded from Side, Turkey, during the March 29, 2006, Solar Eclipse, a geocentric celestial event that was widely seen under nearly ideal conditions.
The composite also captures a pinkish prominence extending just beyond the upper edge of the eclipsed Sun".
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Sunspot-reversed-0.jpgSunspot-905: a sign of an incoming new "Solar Cycle"? (1)54 visiteDa "NASA - Picture of the Day" del 30 Agosto 2006:"Why is sunspot-905 backwards? Perhaps it is a key marker for the beginning of a new Magnetic Cycle on our Sun.
Every 11 years, our Sun goes through a Magnetic Cycle, at the end of which its overall magnetic orientation is reversed. An 11-year Solar Cycle has been observed for hundreds of years by noting peaks and valleys in the average number of sunspots.
Just now, the Sun is near Solar Minimum, and likely to start a long progression toward the most active time, called Solar Maximum, in about 5,5 years".
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The Sun~0.jpgIn the Sun...54 visiteDa "NASA - Picture of the Day", del 21 Settembre 2006:" Though it's 93 MMs away, the Sun still hurts your eyes when you look at it.
But bright Sunlight (along with accurate planning and proper equipment!) resulted in this sharp silhouette of spaceship and space station.
The amazing telescopic view, recorded on September 17, 2006, captures Shuttle Orbiter Atlantis and the International Space Station in orbit over planet Earth.
At a range of 550 Km from the observing site near Mamers, Normandy, France, Atlantis (left) has just undocked and moved about 200 mt away from the Space Station.
Tomorrow (Sept. 22, 2006), yet another satellite of planet Earth can be seen in silhouette - the Moon will eclipse the Sun. This last eclipse of 2006 will be seen as an annular solar eclipse along a track that crosses Northern South America and the South Atlantic".
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