A few lucky people in the Indian Ocean will be treated to a rare event on Monday when an annular solar eclipse will transform the Sun into a dark disc with a blazing ring-shaped corona around its rim.

In solar eclipses, the Moon moves between the Sun and Earth, casting its shadow on the terrestrial surface.

In an annular eclipse, a tiny shift in distance that results from celestial mechanics means the Moon does not completely cover the Sun’s face, as it does in a total eclipse.

Instead, for those directly under the alignment, the Moon covers most of the Sun’s surface, and a ring-like crown of solar light blazes from the edge of the disk.

For those watching from the fringe of the track, the Sun is partially obscured, as if a bite has been taken out of it.

According to veteran NASA eclipse-watcher Fred Espenak, the total eclipse track will run from west to east on Monday from 0606 GMT to 0952 GMT.

It will traverse the Indian Ocean and western Indonesia before petering out just short of Mindanao, the Philippines.

The partial eclipse will be seen in a much wider swathe, including the southern third of Africa, Madagascar, Australia, Southeast India, Southeast Asia and Indonesia.

It will be the only annular solar eclipse this year. The last was on 7 February, 2007, and after Monday, the next one will be on 15 January, 2010.

The big event for eclipse junkies this year is on July 22, when a total solar eclipse will be visible from India and China, the world’s two most populous countries.

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Posturi asemănătoare:

• Alien pool
• Ninsoare pe Marte
• How big are we ?
• Ballet among the stars

Every once in a while, something will appear in the night sky that will attract the attention of even those who normally don’t bother looking up. It’s likely to be that way on Monday evening, Dec. 1.

A slender crescent moon, just 15-percent illuminated, will appear in very close proximity to the two brightest planets in our sky, Venus and Jupiter.

People who are unaware or have no advance notice will almost certainly wonder, as they cast a casual glance toward the moon on that night, what those two “large silvery stars” happen to be? Sometimes, such an occasion brings with it a sudden spike of phone calls to local planetariums, weather offices and even police precincts. Not a few of these calls excitedly inquire about “the UFOs” that are hovering in the vicinity of our natural satellite.

Keep in mind that this head-turning display of three celestial objects crowded together will be merely an illusion of perspective: the moon will be only about 251,400 miles (403,900 km) from Earth, while Venus is nearly 371 times farther away, at 93.2 million miles (149.67 million km). Meanwhile, Jupiter is almost 2,150 times farther away than our natural satellite at 540.3 million miles (869.0 million km).

Those using binoculars or a small telescope will certainly enjoy the almost three-dimensional aspect of the moon, but Venus will be rather disappointing appearing only as a brilliant blob of light, for right now, it’s a small, featureless gibbous disk. That will change in the coming weeks, however, as Venus approaches Earth and the angle it makes between us and the Sun allows it to evolve into a “half-moon” phase in mid January, and a lovely crescent phase of its own during the latter part of February and March.

Jupiter on the other hand is a far more pleasing sight with its relatively large disk, cloud bands and its retinue of bright Galilean satellites. All four will be in view on Monday evening, with Callisto sitting alone on one side of Jupiter, Ganymede, Io and Europa will be on the other side. Io and Europa will in fact, appear very close to each other, separated by only about one-sixth the apparent width of Jupiter.

As beautiful as the view of Venus, Jupiter and the moon will be from North America, an even more spectacular sight awaits those living in parts of Western Europe where the moon will pass in front of Venus.

Astronomers refer to this phenomenon as an “occultation,” taken from Latin, which means “to conceal.” This eye-catching sight will be visible in complete darkness across much of Eastern Europe. Farther west, Venus will disappear behind the dark part of the moon either during evening twilight or just before the Sun sets. When Venus emerges, it will look like a brightening jewel on the slender lunar crescent. For virtually all of Europe, the Sun will have set by then, the exception being southern Portugal (including Lisbon).

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Posturi asemănătoare:

• Ring of fire
• Alien pool
• Ninsoare pe Marte
• How big are we ?

O poză interesantă ce am găsit-o pe net astăzi.

Posturi asemănătoare:

• Ring of fire
• Ninsoare pe Marte
• How big are we ?
• Ballet among the stars

Sonda Phoenix care explorează suprafaţa planetei Marte a descoperit surse de apă pe planeta roşie şi a raportat chiar producerea unei ninsori, au declarat agenţiei de presă AP coordonatorii ştiinţifici ai programului.

Profesorul Peter Smith susţine că, în ciuda faptului că scoarţa planetei are o alcătuire deşertică, ipoteza prezenţei vieţii pe Marte devine din ce în ce mai plauzibilă.

Mai multe detalii puteţi citi pe site-ul oficial.

Posturi asemănătoare:

• Ring of fire
• Alien pool
• How big are we ?
• Ballet among the stars

Posturi asemănătoare:

• Ring of fire
• Alien pool
• Ninsoare pe Marte
• Ballet among the stars