Rabu, 29 Juni 2011

Angin di Kutub Sebabkan Magnet Bumi Rendah

Siklus aktivitas matahari diyakini menyebabkan perubahan gaya magnet bumi meski kedua hal tersebut tidak terjadi secara sinkron. "Tahun 2008 terjadi periode angka titik matahari minimum, tetapi dampaknya terhadap bumi yaitu tercapainya angka minimum daya magnet bumi terjadi setelahnya pada 2009." ketua tim peneliti Lab. Jet Propulsion di Pasadena, California, Bruce Tsurutani dari NASA.
Tingkat aktivitas matahari tersebut dinyatakan dalam angka titik matahari. Ada tiga hal yang menentukan jumlah energi yang diterima dari matahari yang mempengaruhi daya magnet bumi, yaitu kecepatan angin matahari, daya magnet diluar bumi (daya magnet antarplanet), dan arah dari medan magnet. Setelah penelitian mendalam diketahui bahwa daya magnet melemah akibat fenomena 'lubang korona' yang terdapat pada kutub matahari. Lubang tersebut bergerak di lintang rendah matahari dan menuju ke kutub pada tahun 2009.



Saat itulah kecepatan angin matahari di bumi melambat, yang menyebabkan menurunnya daya magnet bumi, yang mengakibatkan munculnya aurora, yakni cahaya indah yang terlihat di kutub bumi.


Dikutip dari KOMPAS, Kamis 16 Juni 2011

Senin, 20 Juni 2011

Story: The Sun & The Wind

THE SUN AND THE WIND

One day, the Sun and the Wind were disputing which wa the stronger. Suddenly they saw a traveler coming down on road, and the Sun said "I see a way to decide our dispute. Whichever of us can cause that traveler to take off his cloak shall be regarded as the stronger. You begin!"
The Sun retired behind a cloud, and the Wind began to blow as hard as it could upon the traveler. But the harder he blew, the more closely did the traveler wrap his cloak round him, till at last the Wind give up in despair.



Then the Sun came out and shone in all his glory upon the traveler. The traveler soon found it too hot to walk with his cloak on. So he take off his cloak and the Sun won they dispute..





Taken from Bahasa Inggris PAKAR

Sabtu, 18 Juni 2011

Story: BUGGY RACES

BUGGY RACES

Once upon a time there lived two bestfriends, the hare and the tortoise. They liked to race against each other, but the hare always won.

One day, the hare asked the tortoise to race down to the beach. The tortoise refused, he said that he will lose anyway. The hare replied in a kind voice that felt sorry about it.




But next day, the hare found a way to race the tortoise that would be fair and lots of fun too. He asked the tortoise to come with him. The tortoise was slowly plodding over the sandhill towards the beach. Now the two friends can race against each other all day and something tells me taht the tortoise might win this time.


Adapted from 50 Bedtime Stories, 2002