The Lick Observatory Series: Scope 2 - The Shane 3-Meter Reflecting Telescope
Introducing the Shane 3-Meter (120-inch) Reflector Telescope at Lick Observatory.
Last week, I talked about the 36-inch Lick *Refracting* Telescope. That scope works similarly to an old school spy glass or like binoculars, and uses lenses to capture light. One issue with this type of telescope is that different wavelengths of light will travel through a lens differently (like how light can be broken into a rainbow simply by traveling through a prism). This affect, known as "chromatic aberration" can create a distorted image.
So today, larger telescopes often use mirrors to focus light instead of lenses. They're called *reflecting* telescopes.
The Shane 3-meter telescope, named after the Lick Director at the time, is a reflecting telescope that was built in 1959. At that time, it was the second largest optical telescope in the world. While it's not even in the top 30 largest today, it's still used for cutting edge research. In fact, the majority of the first 100 exoplanets were discovered based on observations on the Shane 3-meter.
The "3-meter" describes the most important part of any Reflecting telescope: the mirror's diameter.
Mirrors are a HUGE deal in astronomy. They have to be polished with painstaking detail and can be one of the most costly aspects of the scope itself. The Lick Observatory was lucky enough to get the glass for the mirror at-cost of $50,000 (over 50 years ago). To turn the glass into a reflective mirror, required over 4 years of polishing/shaping and then coated with aluminum. This mirror must be cleaned and re-aluminized every ~5 years to obtain optimal reflectivity. Telescopes are so high maintenance!
The Shane 3-meter is a powerhouse of a telescope because it was designed to meet many diverse research needs. It's equipped with multiple instruments, each detecting and recording light from the night sky differently. Time on this telescope is highly coveted, and the type of research conducted has included the discovery of exoplanets and the analysis of supernovae to measure the expansion of the universe. It's also the first telescope with a laser guide-star system (you may see images with a laser pointing out of the dome). This is used as a reference point for an Adaptive Optics system to help correct distortions in images.
The Shane 3-meter can be moved within its huge dome quite easily and quickly. The dome will open wherever the telescope is pointed to allow it to collect light from the night sky. It's a historic and impressive telescope that continues to be useful to astronomers even after 55 years of operation.
Original Article: www.cosmopolitan.com/career/interviews/a47080/get-that-life-emily-calandrelli-outer-space/