Sydney Institute for Astronomy, School of Physics, University of Sydney, Camperdown, New South Wales 2006, Australia.
Nat Commun. 2011 Dec 6;2:581. doi: 10.1038/ncomms1584.
A long-standing and profound problem in astronomy is the difficulty in obtaining deep near-infrared observations due to the extreme brightness and variability of the night sky at these wavelengths. A solution to this problem is crucial if we are to obtain the deepest possible observations of the early Universe, as redshifted starlight from distant galaxies appears at these wavelengths. The atmospheric emission between 1,000 and 1,800 nm arises almost entirely from a forest of extremely bright, very narrow hydroxyl emission lines that varies on timescales of minutes. The astronomical community has long envisaged the prospect of selectively removing these lines, while retaining high throughput between them. Here we demonstrate such a filter for the first time, presenting results from the first on-sky tests. Its use on current 8 m telescopes and future 30 m telescopes will open up many new research avenues in the years to come.
天文学中长期存在的一个深刻问题是,由于这些波长的夜空亮度极高且瞬息万变,因此难以进行深度近红外观测。如果我们要对早期宇宙进行尽可能深的观测,那么解决这个问题至关重要,因为来自遥远星系的红移星光出现在这些波长处。1000 到 1800nm 之间的大气发射几乎完全来自于一片极其明亮、极窄的羟基发射线森林,这些线在几分钟的时间尺度上变化。天文学界一直设想有选择性地去除这些线,同时保持它们之间的高通过率。在这里,我们首次展示了这样一种滤波器,并给出了首次实地测试的结果。它在当前的 8 米望远镜和未来的 30 米望远镜上的使用将在未来几年开辟许多新的研究途径。