27 FEAB. 2004
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On 21 or 22 December every year, the 'solstice' occurs.
For those who live in the southern hemisphere of Earth, on 21/22 December every year is the summer solstice, the year’s longest day. It represents the day when the Sun, as seen from Earth, is furthest south. The winter solstice, on June 21/22, is the shortest day of the year, when the Sun is seen furthest north.
The situation is opposite in the Earth’s northern hemisphere where December has the shortest day and June the longest.
Solstices and the variation of seasons depend on the fact that the rotation axis of Earth is not 'vertical' with respect to its orbital plane around the Sun. The axis is instead inclined by 23 degrees 27 minutes.
Modh meán
19 December
2003: on 19 December 2003, ESA's Mars Express released its Beagle 2 lander and set it on a trajectory for a landing on Mars.
18 December
1958: On 18 December 1958, the world's first communications satellite, SCORE, was launched from Cape Canaveral, United States.
17 December
1903: On 17 December 1903, the Wright brothers flew the first flight in an aeroplane.
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Liostáil lenár nuachtlitir chun an nuacht is déanaí, nuashonruithe misin, agus léargas eisiach a fháil go díreach i do bhosca isteach. Bí ar an gcéad duine a bheidh ar an eolas faoinár dtionscadail agus ár ndul chun cinn atá le teacht.