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Updated: May 26, 2026
10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
A complex multi-notch astronomical filter to suppress the bright infrared sky
J Bland-Hawthorn1, S C Ellis, S G Leon-Saval
1Sydney Institute for Astronomy, School of Physics, University of Sydney, Camperdown, New South Wales 2006, Australia. jbh@physics.usyd.edu.au
Nature Communications
|December 8, 2011
Summary
Astronomers can now achieve deeper near-infrared observations of the early Universe. A new filter selectively removes bright atmospheric hydroxyl lines, overcoming a major obstacle for deep space imaging.
Area of Science:
- Astronomy and Astrophysics
- Optical Engineering
Background:
- Deep near-infrared observations are crucial for studying the early Universe.
- Night sky brightness and variability at near-infrared wavelengths (1,000–1,800 nm) pose significant challenges.
- Atmospheric hydroxyl emission lines are the primary source of this interference.
Purpose of the Study:
- To develop and demonstrate a novel filter for selectively removing atmospheric hydroxyl emission lines.
- To enable deeper astronomical observations in the near-infrared spectrum.
- To overcome limitations in observing the early Universe.
Main Methods:
- Development of a specialized filter designed to block specific hydroxyl emission lines.
- On-sky testing of the filter's performance on astronomical telescopes.
- Evaluation of the filter's ability to maintain high throughput between blocked lines.
Main Results:
- Successful demonstration of a filter that selectively removes atmospheric hydroxyl emission lines.
- First on-sky test results confirm the filter's efficacy.
- The filter retains high throughput in the desired observational windows.
Conclusions:
- The developed filter represents a breakthrough in near-infrared astronomical observation.
- This technology will enhance the capabilities of current (8m) and future (30m) telescopes.
- New research avenues in studying the early Universe will be opened.
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