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Voyagers-00.gifTowards the "Terra Incognita" (1)59 visiteInterstellar Mission - Mission Objective
The mission objective of the Voyager Interstellar Mission (VIM) is to extend the NASA exploration of the Solar System beyond the neighborhood of the outer planets to the outer limits of the Sun's sphere of influence, and possibly beyond. This extended mission is continuing to characterize the outer Solar System environment and search for the heliopause boundary, the outer limits of the Sun's magnetic field and outward flow of the solar wind. Penetration of the heliopause boundary between the solar wind and the interstellar medium will allow measurements to be made of the interstellar fields, particles and waves unaffected by the solar wind.
The VIM is an extension of the Voyager primary mission that was completed in 1989 with the close flyby of Neptune by the Voyager 2 spacecraft. Neptune was the final outer planet visited by a Voyager spacecraft. Voyager 1 completed its planned close flybys of the Jupiter and Saturn planetary systems while Voyager 2, in addition to its own close flybys of Jupiter and Saturn, completed close flybys of the remaining two gas giants, Uranus and Neptune.
At the start of the VIM, the two Voyager spacecraft had been in flight for over 12 years having been launched in August (Voyager 2) and September (Voyager 1), 1977. Voyager 1 was at a distance of approximately 40 AU (Astronomical Unit - mean distance of Earth from the Sun, 150 million kilometers) from the Sun, and Voyager 2 was at a distance of approximately 31 AU.
As of July 2007, Voyager 1 was at a distance of 15.4 Billion Kilometers (103 AU) from the sun and Voyager 2 at a distance of 12.4 Billion kilometers (83 AU).
Voyager 1 is escaping the solar system at a speed of about 3.6 AU per year, 35 degrees out of the ecliptic plane to the north, in the general direction of the Solar Apex (the direction of the Sun's motion relative to nearby stars). Voyager 2 is also escaping the solar system at a speed of about 3.3 AU per year, 48 degrees out of the ecliptic plane to the south.
Both Voyagers are headed towards the outer boundary of the solar system in search of the heliopause, the region where the Sun's influence wanes and the beginning of interstellar space can be sensed. The heliopause has never been reached by any spacecraft; the Voyagers may be the first to pass through this region, which is thought to exist somewhere from 8 to 14 billion miles from the Sun. In December 2004 Voyager 1 crossed an area known as the termination shock. This is where the million-mile-per-hour solar winds slows to about 250,000 miles per hour—the first indication that the wind is nearing the heliopause. Voyager 2 is currently observing preshock phenomena, indicating that it is close to the termination shock. The Voyagers should cross the heliopause 10 to 20 years after reaching the termination shock. The Voyagers have enough electrical power and thruster fuel to operate at least until 2020. By that time, Voyager 1 will be 12.4 billion miles (19.9 billion KM) from the Sun and Voyager 2 will be 10.5 billion miles (16.9 billion KM) away. Eventually, the Voyagers will pass other stars. In about 40,000 years, Voyager 1 will drift within 1.6 light years (9.3 trillion miles) of AC+79 3888, a star in the constellation of Ophiucius. In some 296,000 years, Voyager 2 will pass 4.3 light years (25 trillion miles) from Sirius, the brightest star in the sky . The Voyagers are destined—perhaps eternally—to wander the Milky Way. For current distances, check: Mission Weekly Reports
MareKromium
(14 voti)
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M-45~0.jpgM 45 and Venus55 visite"...L'Opium agrandit ce qui n'a pas de bornes,
Allonge l'Illimité,
Approfondit le Temps, creuse la Volupté,
Et de plaisirs noirs et mornes
Remplit l'ame au-delà de sa capacité..."
Charles Baudelaire (1821 - 1867) - "Le Poison" (1857)
(14 voti)
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CometHale-Bopp-970401C_lodriguss.jpgOn the edge of Oblivion...54 visite"...Mi dispiace vedere che gran parte delle persone vivano la loro Vita non secondo un modello personale - magari discutibile, ma proprio -, bensì secondo il modello creato solo ed esclusivamente dalla televisione (o da chi per essa).
Un modello orrendo e della razza peggiore.
Certo, non esiste un modello predefinito di "Vita" e allora ognuno di noi cresce assieme a quello che gli sta attorno, aiutandosi con quanto si trova in giro. Però...
Però vedo sempre più maiali inconsapevoli di viaggiare verso il mattatoio e, anche se dovrei (forse) preoccuparmi più di me stesso, questa visione - un pò - mi duole..."
Giorgio Picciau - "Lettere"MareKromium
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SPACEVISION-P-019-05703.jpgSpace-Vision56 visite
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Perseid-2.jpgShooting Star (2) - detail mgnf62 visiteOsservate questo ingrandimento della Perseide immortalata dal nostro Amico Jimmy Westlake e poi provate a riguardare il (presunto) bolide che Cassini potrebbe aver fotografato nello Spazio di Saturno: noterete con semplicità che le caratteristiche delle due "strisciate di luce" (streaks) sono MOLTO simili.
Peccato che la NASA si affanni a dare credito solo ad alcuni personaggi e ad alcune (sempre più discutibili o insulse) "scoperte" (come il presunto colorito "rosato" di Iperione), senza mai prendere atto che anche in Italia esistono Ricercatori attenti e competenti i quali, di tanto in tanto, sono i primi a notare l'esistenza di qualcosa di veramente raro...
Peccato.
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In the Mind-1.jpgIn the mind73 visitenessun commento
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Tomorrow.jpgTomorrow never dies...63 visitenessun commento
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Moonrise.jpgThe "Moon Illusion"...From Cape Sounion185 visiteDa "NASA - Picture of the Day" del 23 Giugno 2005:"The Moon was full this month on June 22nd, only a day after the northern hemisphere's summer solstice. Since this solstice marked the northernmost point of the Sun's annual motion through planet Earth's sky, the full Moon rising near the ecliptic plane opposite the Sun was at its farthest south for the year. Only a month earlier, on May 23rd, astronomer Anthony Ayiomamitis recorded this picture of another southerly full Moon rising above Cape Sounion, Greece. The twenty-four hundred year old Temple of Poseidon lies in the foreground, also visible to sailors on the Aegean Sea. In this well-planned, single exposure, a long telephoto lens makes the Moon loom large, but even without optical aid casual skygazers often find the full Moon looking astonishingly large when seen near the horizon.
That powerful visual effect is known as the Moon Illusion".
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Sun_Pillar_in_blue_and_violet.jpgSun Pillar from Lake Tahoe - Nevada State Park (USA)112 visiteCaption originale NASA: "Sometimes the unknown is beautiful. In 2000 February near Lake Tahoe, Nevada, two amateur photographers noticed an unusual red column of light rise mysteriously from a setting sun. During the next few minutes, they were able to capture the pillar and a photogenic sunset on film. Pictured above, the red column is seen above a serene Lake Tahoe and snow-capped mountains across from Lake Tahoe-Nevada State Park. The mysterious column, they learned later, is a Sun Pillar, a phenomenon where sunlight reflects off of distant falling ice crystals".
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Sun_Pillar.jpgA light "Sun-pillar" from somewhere in USA85 visiteCaption originale NASA. "Have you ever seen a sun pillar? When the air is cold and the Sun is rising or setting, falling ice crystals can reflect sunlight and create an unusual "column of light". Ice sometimes forms flat, stop-sign shaped crystals as it falls from high-level clouds; air resistance causes these crystals to lie nearly flat much of the time as they flutter to the ground. Then sunlight reflects off crystals that are properly aligned, creating the so-called "Sun-pillar" effect".
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First_Snow-MF-LXTT.jpgFirst Snow (by Marco Faccin)206 visitenessun commentoMareKromium
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ColorfulReality.jpgEmissions (by Marco Faccin)54 visitenessun commentoMareKromium
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