When it comes to peering into the sky and taking a look at planets and stars, where would you be without a telescope? In this article, we will learn about some of the different kinds of telescopes that were invented during the 17th century, including the Cassegrain model, which used wide-angle reflecting components. A handful of inventors and other inventions are also mentioned.
The Cassegrain telescope consists of wide-angle reflecting components and a concave mirror that receives light and is used to focus on images. A second mirror on the telescope reflects light through a gap in the primary mirror and works in conjunction with an eyepiece or camera that is mounted at the back end of the tube. In 1672, a French sculptor by the name of Sieur Guillaume Cassegrain created the reflecting telescope, which was named after him.
Many centuries later, an Estonian astronomer and lens-maker named Bernard Schmidt (1879-1935), would add a correcting plate (a type of lens), which made a new version called the Schmidt-Cassegrain telescope, which lessened the spherical deviation of Cassegrain’s first invention.
A Scottish mathematician named James Gregory (1638-1675) is the man behind the first reflecting telescope, which he produced in 1663. That same year, he published a description of what the invention in the “Optica Promota.” In the end, he never actually pieced together a telescope, which he described as using a parabolic and an ellipsoidal mirror. But , without ideas , no one would move forward. Sometimes, this type of
Many strides were made in constructing the telescope and Christian Huygens (1629-1695) was a Dutch physicist and astronomer, who developed a new way of grinding and polishing glass telescope lenses. His efforts came around 1654, where he aided the establishment of more current, stronger telescopes. Huygens is also credited with identifying the rings of Saturn and discovered Titan, which is the largest of Saturn (1655). Another invention Huygens is responsible for is the pendulum clock, which he designed in 1656. His version worked without springs. In 1655, he also became the first to write on calculus and probability, as well as later proposed the wave theory of light in 1678.
The device known to measure air pressure is called a barometer, which calculates the weight of the “column of air that extends from the instrument to the top of the atmosphere.” Today, there are two kinds of barometers commonly in use – mercury and aneroid (without fluid). The earliest barometers of the 17th century were made of water and known as “storm glasses.”
In 1643, the mercury barometer was created by a pupil of Galileo , an Italian physicist named Evangelista Torricelli (1608-1647). Torricelli found a way to invert a glass tube containing mercury into another vessel of mercury and learned that the mercury in the tube had a way of weighing the air within the atmosphere of the above tube. In later years, the aneroid barometer, which actually uses a spring balance instead of liquid, was the product of a French scientist named Lucien Vidie.
Born during the late 1500s, Hans Lippershey was a German-born Dutch lens maker, who presented the first refracting telescope, which used two lenses in its construction. In 1608, he applied for a patent for his optical invention, which he aimed to present to the military as a suitable device. In a refracting telescope, the large primary lens is responsible for completing most of the magnification. Later, Newton would improve upon his design of telescope, which would become known as the Newtonian telescope.