THE Yerkes Observatory, which has recently been completed and inaugurated, contains in its instrumental equipment the largest refractor in the world, the diameter of the object-glass spanning 40 ...

I'm often asked to recommend a telescope, especially around the holidays, when gift-giving is on our minds. Today I'll share a few suggestions, but before we talk specifics, let's look at the ...

The Celestron Omni XLT 120 is made for the seasoned skywatcher, who is looking for that sought-after combination of high-quality build and superb views of the solar system and lunar surface. While a ...

The Celestron Astromaster 102AZ might seem like the ideal compromise for a beginner's telescope, but being okay at everything means it doesn't really stand out for any particular subject. Why you can ...

IT has been supposed that the difference between the zenith distance of a star obtained by direct observation and that obtained by observing it reflected in a pool of mercury—as it is not fully ...

The original instrument to occupy the 25-foot diameter dome was the 10.5-inch Bausch refracting telescope (f/15.5) installed in the brand new observatory in 1953. Bausch & Lomb Company gave the ...