Auroras - Paintings In The Sky -
http://nationalatlas.gov/articles/geology/IMAGES/aurora.gifFar north in the night sky, a faint glow appears on the horizon. Green and red flames of light stretch across the sky. A glowing curtain of light forms, waving and swirling above you. As the lights fade away the dark night closes over you once again.
What makes them happen?
The voltage pushes electrons (which are very light) toward the magnetic poles, accelerating them to high speeds, much like the electrons in a TV picture tube that accelerate to hit the screen. They zoom along the field lines towards the ground to the north and south, until huge numbers of electrons are pushed down into the upper layer of the atmosphere, called the ionosphere.
In the ionosphere, the speeding electrons collide violently with gas atoms. This gives the gas atoms energy, which causes them to release both light and more electrons. In this way, the gases of the ionosphere glow and conduct flowing electric currents into and out of the polar region. The electrons flowing back out don't have as much energy as the speedy incoming ones had - that energy went into creating the aurora!
Where Can You See Aurora?
The best places to see auroras are near the magnetic poles. These include areas of northern Greenland, the Scandinavian coast, Siberia , and Alaska in the north, and Antarctica in the south. But when planning your trip remember: places above the arctic circle have round-the-clock sunlight during about April to September! This can make aurora viewing difficult. And the aurora australis might be observed by many penguins from May to September, but even scientists do not go out much during the Antarctic winter!
[ Last edited bypenglipur at 16-5-2006 04:06 PM ] What Do Aurora Looks Like?
Picture yourself outside on a clear dark night. Low on the horizon you notice a faint glow of greenish light which forms an arch, stretching lazily across the sky. As time passes, additional bands of light form and drift overhead, slowly brightening to form giant curtains in the sky that slowly wave as if a gentle breeze were blowing. Suddenly, the bottom of the curtains brighten with a reddish tint and ripple faster. Blues and purples appear. As the curtains pass directly overhead, you see bright points of light that swirl like a pinwheel. The entire sky seems to be full of color and motion. Then, after several minutes, everything fades into a warm green glow.
http://www.exploratorium.edu/learning_studio/auroras/images/jcbandarc.jpg
Ontario,Eastern Canada
http://www.exploratorium.edu/learning_studio/auroras/images/can_aurora1.jpg
Mount Wilson,Southern California
http://www.exploratorium.edu/learning_studio/auroras/images/mtwilson3.31.jpg
[ Last edited bypenglipur at 16-5-2006 04:30 PM ]
Aurora in Alaska
http://www.ptialaska.net/~hutch/nlbghse.jpghttp://www.ptialaska.net/~hutch/200.jpg
http://www.ptialaska.net/~hutch/1698pu.jpg
http://www.ptialaska.net/~hutch/nlraft.jpg
[ Last edited bypenglipur at 16-5-2006 04:30 PM ] http://www.aldebaran.cz/actions/2002_aurora/aurora/180s.jpg
http://www.aldebaran.cz/actions/2002_aurora/aurora/020s.jpg
http://www.aldebaran.cz/actions/2002_aurora/aurora/240s.jpg
http://www.aldebaran.cz/actions/2002_aurora/aurora/120s.jpg
[ Last edited bypenglipur at 16-5-2006 04:31 PM ]
Alaska -Fisheye Ers-
http://www.alaska.com/ips_rich_content/893-aurora-fisheye-ERS.jpg Aurora ClassificationsHA @ Homogeneous -Arc Regular form in height, direction and intensity.
HB @ Homogeneous -Band Same as HA, but variable along length.
RA @ Rays Arc -Same as HA, luminosity quasi vertically structured.
RB @ Rays Band -Same as RA, luminosity quasi vertically structured.
DS @ Diffuse Surface -Uniform emitting area.
PS @ Pulsating Surface -Same as DS, but intensity variable in time (several seconds).
PA @ Pulsating Arc -Same as HA, but intensity variable in time (several seconds).
C@ Corona -Ray system parallel to the magnetic field lines.
F@ Flaming -Forms of variable intensity moving towards zenith. Why are they Different colours?
Streetlights and neon signs are filled with gas. When they are turned on, an applied voltage energizes electrons in the gas. These electrons strike the gas molecules, which excites them to emit light. The color of the light you see depends on the type of gas.
Every gas shines with its own special colors of light. These colors are like a fingerprint because no two gases give off exactly the same colors. Streetlights filled with sodium gas give off a dark yellow light. Only sodium atoms give off that particular shade of yellow. Orange neon signs are filled with pure neon gas. Other colors of neon signs are actually neon mixed with other types of gases, like helium or argon.
The unique colors of light produced by a gas are called its "spectrum". The auroral lights' colors are determined by the spectra of gases in the Earth's atmosphere, and the height at which the most collisions take place. Incoming particles tend to collide with different gases at different heights.
http://www.exploratorium.edu/learning_studio/auroras/images/jcallred.jpg
Rare high-altitude red aurora,cause by a violent solara outburst near solar maximum.
http://www.exploratorium.edu/learning_studio/auroras/images/jcrededge.jpg
A curtain aurora with red edges. lawa kan aurora nih....
nak jugak pegi tgk betul2...
korg pernah tgk aurora yg betul2 tak?:cak: Originally posted by penglipur at 16-5-2006 01:32 AM
lawa kan aurora nih....
nak jugak pegi tgk betul2...
korg pernah tgk aurora yg betul2 tak?:cak:
Lawa kalo tgk secara live..:bgrin:
Kat sini tempat mez kaler Aurora hijau aje di akhiri dgn kaler pink dan sket kaler orange tp sekejap aje.
Mez slalu tgk Aurora... bergantunglah jugak dgn keadaan cuaca di langit.
Slalunya mez tgk between spring, summer dan masa winter. Berikut adalah koleksi gambar Aurora sepanjang yg Mez ambik.
http://nwpixels-auroraborealis.buzznet.com/user/photos/
http://nwpixels-northernlights.buzznet.com/user/photos/
http://nwpixels-auroraborealis2.buzznet.com/user/photos/
:love: Aurora. Tahun ni nak ambik gambar Aurora lagi....area Mez ni ngam2 Aurora tu terjadi dan dekat plak Science centre. ni yg org panggil Northern Light tu kan?
Reply #11 archilless's post
a'ah :hatdown:Reply #10 aimez's post
bestnyer mez!!!!bila la bleh join mez tgk aurora nih... :bgrin: Originally posted by penglipur at 18-5-2006 09:26 AM
bestnyer mez!!!!
bila la bleh join mez tgk aurora nih... :bgrin:
Penglipur duk kat ner? Dekat bolehlah join skali ngan mez.:bgrin: Mez suka tul gambar Aurora yg di ambik oleh mamat Norway nih cun giler...!:hatdown:
http://newton-i.usefilm.com/images/3/9/0/8/3908/1000660-medium.jpg puhh comelnya, apsal kat umah aku takde mende ni cantiknya...SUBHANALLAH.. Originally posted by aimez at 23-5-2006 12:53 AM
Penglipur duk kat ner? Dekat bolehlah join skali ngan mez.:bgrin:
masih kat malaysia...:bgrin:
i/Allah,kalau ada rezeki sampai jugak kat yellow knife..
memburu aurora....:pmuka: Originally posted by penglipur at 25-5-2006 12:11 PM
masih kat malaysia...:bgrin:
i/Allah,kalau ada rezeki sampai jugak kat yellow knife..
memburu aurora....:pmuka:
The best time tgk aurora di sekitar bln August - April.
Pigi kat Aurora Village atau Fairbanks Alaska & Whitehorse.
sana bkn jer leh tgk aurora, dog sled, snowmobile tours etc...
Kat Fort MacMurray, Alberta pun ok jugak.
Kat tempat aku ni kdg2 tak menentu bulan bila aurora tu muncul...
dlm umah pon leh nampak..:bgrin: Wahh semua dok sebut2 nick aku ni. Aku pun peminat aurora, malangnya tak pernahdapat tengok betul2.
Nick ni aku dapat lebih kurang 20 tahun dulu, buat presentation pasal aurora dalam kelas intensif English.Masa tu hampir semua orang tak tau apa pun pasal aurora ni, dan ditambah dengan English aku yang berterabur, lagilah diaorang pening, tak boleh bayangkan. Masa tu mana ada multimedia nak tayang2 gambar aurora ni.
Last2 diaorang panggil je aku Aurora.
Tengok aurora dari angkasa:Gambarni di utara Canada, tapi nampak macam terbalik agaknya masa proses ambik gambar.
http://antwrp.gsfc.nasa.gov/apod/image/0511/spaceaurora_iss_big.jpg
Aurora selain cantik, dia juga sebagai tanda di mana kutub2 magnet berada.Dan dalam masa 10 tahun ni, kutub magnet dah berubah beberapa degree.
Kutub utara magnet dan selatan bumi sebenarnya dah switch beberapa kali.
Mengikut saintis, pertukaran itu berlaku hampir setiap 700,000 tahun sekali.Sebabnya medan magnet actuallynya random, but the strongest dan sampai ke luar bumi yg dipole tu la, satu kat kutub utara dan satu lagi kat selatan. Yang lain2 tak sempat keluar dah lemah.
Tapi akan ada waktu, yg random tadi bertambah kuat, dan waktu tu kita akan dapati magnetic poles di beberapa tempat kat bumi. So kemungkinan kalau nasib baik, masa tu kita dapat tengok aurora di Malaysia.Sampai akhirnya jadi tenang semula, dan dipole macam sekarang ni terbentuk semula, tapi dengan kemungkinan kutub utara dan selatan magnet dah berubah tempat.
http://science.nasa.gov/headlines/y2003/29dec_magneticfield.htm
Buat masa ni planet Mars tak ada dipole magnet yg kuat macam di bumi.Tapi saintis percaya satu masa dulu dia. Sekarang ni saintis cuma dapat kesan beberapa medan magnetik yg lemah di beberapa tempat. Adakah bumi akan jadi macam ni nanti?
http;//mars.columbus2space.org/RecreatingCrustalMagneticSourcesMars2.doc