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討論區 => 天文新知 => 主題作者是: peter 於 2017-04-12 10:26:12



主題: 木星發現 大冷斑 Great Cold Spot
作者: peter2017-04-12 10:26:12
https://www.sciencedaily.com/releases/2017/04/170411090157.htm
(https://images.sciencedaily.com/2017/04/170411090157_1_540x360.jpg)

The Great Cold Spot was first discovered on Jupiter using observations taken of Jupiter's auroral region by the CRIRES instrument on ESO's Very Large Telescope. The images on the left show the bright arcs of Jupiter's infrared aurora on two separate nights, the top left image on 17 October and three images taken 31 December 2012, as the planet slowly rotates. However, the Great Cold Spot cannot be seen clearly until these images are saturated so that the entire aurora becomes white, as shown on the right. Here, the planet glows as a result of the temperature of the upper atmosphere, and the distinct regions of cooling that reveal the Great Cold Spot can be seen. Based on data from VLT/ESO.


主題: 回覆: 木星發現 大冷斑 Great Cold Spot
作者: peter2017-04-12 22:01:10
天文学家发现“大冷斑” 
http://www.cnbeta.com/articles/science/601849.htm

木星足够大能够容纳下不止一个大斑点。日前,英国莱斯特大学的天文学家们表示,他们在这颗星球上发现了除“大红斑(Great Red Spot)”之外的另外一个大斑点,他们叫它"Great Cold Spot(暂译大冷斑)"。据了解,这颗大冷斑跟大红斑差不多大小,经过研究发现它由木星的高能极光形成。它的经度和维度分别为2.4万千米和1.2万千米,另外它的温度要比其周围大气的温度低上20%至30%。

该项研究负责人Tom Stallard博士指出,大冷斑要比变化缓慢的大红斑波动更大,它可能在几天或几周内之间就会发生形状和大小的变化,但后来又能重新恢复到原来的样子。
另外,他还补充道,大冷斑很有可能拥有一个分解、重组的周期,这可能可以追溯到几千年前。不像地球的极光依靠太阳的是,木星的极光则受火山卫星Io气体的控制。

Stallard表示,大冷斑的发现是一个真正的惊喜,这意味着木星上层大气可能还有其他一些天体现象等着被发现。

(http://static.cnbetacdn.com/thumb/article/2017/0412/817a7c362c7c7b6.jpg)

据悉,Stallard等人的相关研究报告已发表在《Geophysical Research Letters》上。


(http://static.cnbetacdn.com/article/2017/0412/8a3e5837e846fa9.jpg)