Northern Lights From Space (太空中的北極光) @ Andrewl8510的部落格

( 2/10 即將有一波強烈北極光入侵地球) , 以下文章由 Andrew Ling 翻譯自美國太空氣象網站

NORTHERN LIGHTS FROM SPACE: The solar wind is buffeting Earth's magnetic field and igniting a ring of auroral light around the North Pole. A great place to see the show is Earth orbit. Last night, the US military's DMSP-18 weather satellite photographed the action over northern Europe:

"This night-time image shows a band of aurora borealis north of Norway at 1817 GMT on Feb. 1st," says Paul McCrone, who processed the image at the US Navy's Fleet Numerical Meteorology and Oceanography Center (FNMOC) in Monterey, California.

To the low-light cameras of DMSP-18, the auroras were as easy to see as the city lights of Scandinavia, France and the UK. If that band of light had descended over a populated area, onlookers would have enjoyed quite a display.

Another solar wind stream is en route to Earth and it should be stronger than the one we're experiencing now. High latitude sky watchers and weather satellites should be alert for auroras when the stream arrives on or about Feb. 10th.

太陽風正撞擊著地球的磁場, 並在北極附近點燃了一個環形的極光. 觀看這場天文秀的絕佳的位置就是在地球的軌道. 昨晚美國的軍用氣象衛星 DMSP-18 在北歐上空拍攝了這極光活動.

Paul McCrone 說明 "在 2/1 格林威治時間 18:17 夜間的影像顯示了在挪威北部極光的頻帶" , 他在美國加州的Monterey 海軍艦隊海洋氣象數據中心加工處理了這張照片.

在DMSP-18 的暗光相機, 很容易在斯堪的那維亞半島, 法國, 英國的城市燈光之下看到北極光. 假設極光的頻帶在人口密集區上空遞減, 觀眾仍將可以盡情欣賞這極光秀.

另外一個太陽風正依原定的路線朝向地球, 而且它將比我們現在所期待的更強烈. 太陽激流大約在 2/10 抵達地球, 到時將發佈北極光警報給高緯度天空的觀測者與氣象衛星.

Hundreds of years ago, the brightest things on the night side of Earth were Northern Lights. After nightfall, the continents went dark while polar regions lit up with solar wind-powered auroras. How times have changed. Consider the following satellite imagery of Europe and parts of North America on Feb. 3rd:

"The auroras are still there--"note the luminous arcs over northern Canada and Scandinavia," McCrone points out--but now they have competition in the form of city lights. Indeed, the balance of power seems to have shifted sharply from Birkeland to Edison.

The balance could be restored, temporarily at least, on Feb. 10th when a solar wind stream is due to hit Earth. The impact will energize the arctic lights, boosting their luminosity for a nice show at high latitudes.

數百年前, 在地球的夜間最亮的的光就是北極光, 在夜沉之後北極區被太陽風點燃成有威力的極光而讓大陸走出暗夜. 從 2/3 的歐洲與北美部分地區的衛星畫像想想吧, 這時代已經變了.

McCrone 指出 "北極光仍然在那裡", 發亮的電弧光就在加拿大與斯堪的那維亞半島的上空", 但現在它跟城市燈光競爭. 從 Birkeland 到 Edison 這兩者學者都確實認為這平衡的力量看起來有劇烈的轉變了.

當太陽風在 2/10 到時侵襲地球時, 至少這樣的平衡能夠被短暫恢復的. 這樣的衝擊將供給北極光能量, 提高光度讓在高緯度地區有個美好的極光秀.