Tomorrow April 10 marks the 85th anniversary of the Hale Telescope 200-inch mirror blank arriving to Caltech from Corning NY, where it was cast. The largest (future) telescope mirror in the world had traveled for 16 days, 3400 miles across the United States by rail. It was a journey that captured the public’s imagination—thousands would stand along the route to watch the “Big Eye” go by. The Pyrex 200-inch disk arrived safely at Caltech on April 10, 1936. To celebrate the anniversary of this Pal

1.2K views · 13 reactions | The Hale Telescope is used every night for astronomical research thanks to a modern and evolving instrument suite. Hale Telescope instruments provide a wide range of imaging and spectroscopic capabilities in the optical and near-infrared parts of the electromagnetic spectrum. https://sites.astro.caltech.edu/palomar/about/telescopes/hale.html#instruments | Palomar Observatory | Facebook

Observatory Closure Notice The observatory will be closed to the public on Wednesday, 11/5, and Thursday, 11/6 while the 200-inch mirror is cleaned and re-aluminized. ✨ This special aluminizing process only happens every two years and is essential for keeping the telescope performing at its best. What is the aluminizing process like? It involves carefully removing, cleaning, and coating the giant mirror with a thin layer of aluminum to ensure maximum reflectivity — a truly fascinating behind-the

Palomar Observatory’s 48-inch Samuel Oschin Telescope is one of the...

43 reactions · 13 shares | The Hale Telescope is used every night for...