explorer blog

Welcome: May 2006

Thursday, May 25, 2006

Sun Bear or Honey Bear :

the smallest and least known of bears. Sun bears are black with a very large yellow or white crescent on their chest, have very short hair, and have five long claws on their front feet for tearing open bee trees and insect sites. They are spread across south-eastern Asia from Myanmar and Thailand to Indonesia and Borneo. They have the typical plantigrade (flat) feet of bears, and their soles are almost totally devoid of hair, which may be an aid in climbing trees. Their alternative name, the honey bear, is indicative of their main food source. They have a very long tongue, possibly to aid them in reaching insects and honey.

Sun bear females weigh as little as 30 kg (66 lb), the males little more than 65 kg (145 lb). Without adequate range, they increasingly feed on agricultural crops and gardens, causing damage.
Little is known about the breeding activity, reproduction, or family life of this species. Their habitat is declining rapidly because of intense human impact, and they may become extinct in the wild in the next few decades. They are excellent climbers, and spend considerable time in trees, perhaps even sleeping there. As with other bears, they are being hunted excessively for their gall bladders, which are used in traditional Chinese medicine, or paws, used for soup. They can be very dangerous in close jungle encounters

Wednesday, May 24, 2006

The Corona:

During total solar eclipses, as the Moon completely obscures the dazzling light of the photosphere, it briefly becomes possible to see the outer solar atmosphere, which extends for several solar radii from the disc of the Sun: the corona. The corona reaches from just above the chromosphere far out into interplanetary space. Some indication of its great extent is given by observations from satellites equipped with coronagraphs; results in X-ray wavelengths, particularly, from such spacecraft as Yohkoh and SOHO, clearly show the corona to be an active, dynamic environment.

Most of the corona consists of great arches of hot, ionized gas (plasma): smaller arches within active regions and larger arches between active regions. The corona is shaped by the extended solar magnetic field. Closed magnetic field loops above active regions give rise to bright structures, described as “helmets”. Regions of open magnetic field, where only one end of the field line is embedded in the Sun, give rise to long “streamers” extending radially away from the Sun.

The shape of the corona changes over the sunspot cycle. At sunspot maximum, when active regions are abundant, the corona consists mainly of evenly distributed closed loops; at minimum, long streamers extend to either side of the Sun, mainly from its equatorial regions. Around sunspot maximum, when flare activity is common, the corona in X-ray wavelengths is frequently seen to be disturbed by outward-travelling shock waves. These coronal mass ejections (CMEs) have become recognized as an important source of turbulence in the solar wind. CMEs directed towards Earth can cause magnetic storms. A primary aim of the SOHO satellite mission is to observe CMEs with a view to forecasting such disruption. In 1999 X-ray observations made by Yohkoh linked CMEs to the appearance of sigmoids, S-shaped formations on the photosphere (inverted in the Sun's northern hemisphere) some 160,000 km (100,000 mi) long, which may indicate the magnetic field twisting back on itself. The data indicated a strong statistical correlation between the appearance of sigmoids and the subsequent eruption of CMEs.

In the 1940s the corona was discovered to be much hotter than either the photosphere or the chromosphere, with a temperature of over 1 million K (1.8 million degrees F). Finding the mechanism by which this energy reaches the corona is one of the classic problems of astrophysics. Early ideas to account for coronal heating included the dissipation of acoustic waves produced by the motion of the turbulent solar granules. Through further analysis, it became apparent that such waves would give up their energy before reaching coronal heights. Propagation of gravitational waves was rejected for similar reasons. The most widely accepted theory suggests that the corona is heated by energy carried by magnetic loops emerging from the deep solar interior. The Yohkoh and SOHO spacecraft have provided ample observational evidence to support the idea that considerable magnetic energy is transferred to the corona via CMEs and other transient phenomena.

Monday, May 22, 2006


The original Roman calendar, introduced about the 7th century BC, had 10 months with 304 days in a year that began with March. Two more months, January and February, were added later in the 7th century BC, but because the months were only 29 or 30 days long, an extra month had to be intercalated approximately every second year. The days of the month were designated by the awkward method of counting backwards from three dates: the calends, or first of the month; the ides, or middle of the month, falling on the 13th of some months and the 15th of others; and the nones, or 9th day before the ides. The Roman calendar became hopelessly confused when officials to whom the addition of days and months was entrusted abused their authority to prolong their terms of office or to hasten or delay elections.

In 45 BCJulius Caesar, on the advice of the Greek astronomer Sosigenes (flourished 1st century BC), decided to use a purely solar calendar. This calendar, known as the Julian calendar, fixed the normal year at 365 days, and the leap year, every fourth year, at 366 days. Leap year is so named because the extra day causes any date after February in a leap year to “leap” over one day in the week and to occur two days later in the week than it did in the previous year, rather than one day later, as in a normal year. The Julian calendar also established the order of the months and the days of the week as they exist in present-day calendars. In 44 BC Julius Caesar changed the name of the month Quintilis to Julius (July), after himself. The month Sextilis was renamed Augustus (August) in honour of Caesar Augustus, who succeeded Julius Caesar. Some authorities maintain that Augustus established the lengths of the months we use today.

Thursday, May 18, 2006

Sunday, May 14, 2006


second day of the week, derived from the Anglo-Saxon monandaeg, which means “the Moon’s day”. Its Latin equivalent is dies lunae,”day of the Moon”. For the Anglo-Saxons the second day was sacred to the goddess of the moon. In German the second day is Montag; in French, lundi; and in Italian, lunedì.
“Blue Monday”, a term used to indicate the dismal beginning of the working week, was originally used because, on the Monday before Lent, churches were draped in blue cloth, symbolizing penitence


The ancient Babylonians had a lunisolar calendar of 12 lunar months of 30 days each, and they added extra months when necessary to keep the calendar in line with the seasons of the year. The ancient Egyptians were the first to replace the lunar calendar with a calendar based on the solar year. They measured the solar year as 365 days, divided into 12 months of 30 days each, with 5 extra days at the end. About 238 BC King Ptolemy III ordered that an extra day be added to every fourth year, which was therefore similar to the modern leap year. In ancient Greece a lunisolar calendar was in use, with a year of 354 days. The Greeks were the first to intercalate extra months into the calendar on a scientific basis, adding months at specific intervals in a cycle of solar years.

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