Capella is a star system of four stars in the constellation of Auriga,
appearing as a single star to the naked eye. It is the third-brightest
star or star system in the northern celestial hemisphere, after Arcturus
and Vega. Always above the horizon for observers north of 44°N, the
Capella system is only 42.9 light-years from the Sun. Its two largest
stars are Capella Aa and Capella Ab, bright yellow giant stars in a
binary pair, both around 2.5 times as massive as the Sun. They are in a
very tight circular 104-day orbit, some 0.76 astronomical units (au)
apart. Capella Aa is the cooler and more luminous of the two, with
around 79 times the Sun's luminosity. An ageing red clump star, it is
fusing helium to carbon and oxygen in its core. Ab is slightly less
massive, smaller and hotter, about 73 times as luminous as the Sun. The
Capella system is one of the brightest sources of X-rays in the sky,
thought to come primarily from the corona of the more massive giant. The
other two stars, a binary pair around 10,000 au from the first two, are
faint, small and relatively cool red dwarfs.
Read more: <https://en.wikipedia.org/wiki/Capella>
Today's selected anniversaries:
Archbishop of Canterbury Thomas Cranmer, one of the founders of
Anglicanism, was burnt at the stake in Oxford, England, for heresy.
First World War: The German Army opened the Spring Offensive
with Operation Michael, attempting to break through the Allied lines and
to seize ports on the English Channel.
The first major rock and roll concert, the Moondog Coronation
Ball, was held at the Cleveland Arena in Cleveland, Ohio, U.S.
War of Attrition: The Israel Defense Forces clashed with the
Palestine Liberation Organization and the Jordanian Armed Forces during
the Battle of Karameh (aftermath pictured).
A man using a hammer smashed the statue of Phra Phrom in the
Erawan Shrine in Bangkok, Thailand, and was subsequently beaten to death
Wiktionary's word of the day:
1. Pertaining to the forest, or woodlands.
2. Residing in a forest or wood.
3. Wooded, or covered in forest.
Wikiquote quote of the day:
When the full-grown poet came, Out spake pleased Nature (the round
impassive globe, with all its shows of day and night,) saying, He is
mine; But out spake too the Soul of man, proud, jealous and
unreconciled, Nay he is mine alone; — Then the full-grown poet stood
between the two, and took each by the hand; And to-day and ever so
stands, as blender, uniter, tightly holding hands, Which he will never
release until he reconciles the two, And wholly and joyously blends
--Leaves of Grass
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