在南极洲A圆顶进行夜间观测
Bin Ma1,2, Zhaohui Shang3,4, Yi Hu5
1National Astronomical Observatories, Chinese Academy of Sciences, Beijing, China. bma@nao.cas.cn.
Nature
|July 31, 2020
概括
在A圆顶进行的天文观测显示,夜间的条件非常好. 薄薄的边界层使得景色更清晰,与其他地点的高海拔相比.
科学领域:
- 天文学与天体物理学
- 大气科学
背景情况:
- 天文视觉,星光被大气流所模糊, 对于现场质量至关重要.
- 南极高原提供弱的自由大气动荡,但具有强大的边界层.
- 之前在A圆顶的测量仅限于白天.
研究的目的:
- 测量A圆顶上的夜间天文观测.
- 描述 A 圆顶的大气边界层.
- 评估A圆顶作为一个天文观测站点的潜力.
主要方法:
- 使用差异图像运动监测器进行夜间视觉测量.
- 与近地温度梯度相关的视觉数据.
- 使用声波雷达确定边界层的厚度.
主要成果:
- 在8米高处看到0.13弧秒.
- 实现了0.31弧秒的中位视力,相当于C圆顶的20米高度测量.
- 发现了视力,边界层厚度和近地表温度梯度之间强烈的相关性.
- 确定A圆顶的中间边界层厚度大约为14米.
结论:
- 圆顶A展现出出色的夜间天文观测条件.
- 圆顶A的薄边界层可以更好地进入空气.
- A 是一个非常有前途的天文观测场所.
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