A HISTORIC 85-year-old telescope has returned to the cutting edge of astronomy.
The 2.5-metre telescope on California’s Mount Wilson was the world’s largest for 30 years, and still benefits from the exceptionally steady air that let Edwin Hubble see distant galaxies with unprecedented clarity. But in the mid-1980s scattered light from nearby Los Angeles grew so bad that the telescope was closed down.
The Mount Wilson Institute revived the telescope in 1991, and later added adaptive optics to sharpen its vision. Now Jian Ge of Pennsylvania State University has switched the telescope to infrared wavelengths that are less affected by…
