Comenius - Following the Famous Scientists

Scientific Methods



Uppdated 2010-06-07


Tycho Brahe
- Scientific Methods


  • Brass azimuthal quadrant The azimuthal quadrant was the first of Tycho Brahes instruments built at Hveen. It was built in between the years of 1576 and 1577, had a 65cm radius and an accuracy of 48.8 seconds of arc. Its intended use was for observation of a comet in 1577.
  • Computational globe "Tycho's great globe" had a radius of 1.6m and took over ten years to construct. The main reason for this was that Tycho wanted it to be perfectly spherical. After this was ensured, the whole construction was covered in brass plates, to form an even globe. It wasn't ready for use before late 1980. The primary use of the globe was to let Tycho record the positions of observed stars and planets. This was done by converting the azimuth/altitude coordinates of his observations, into celestial coordinates. By the end of 1595, Tycho had over 1000 stars inscribed stars on his globe.
  • Armillary sphere The armillary sphere was constructed in 1581 and measured 1.6m in radius. Tycho wasn't content with this version of the sphere, because the size and weight of the various large components caused the whole construct to bend slightly and thus compromised the accuracy. Tycho's everlasting strives for perfection, led to the design of the later equatorial armillaries.
  • Triangular sextant The triangular sextant was built in 1561 and had a 1.6m radius. As Tycho's instruments became larger and larger, they had to be mounted in a fixed position. But thanks to a special "globe mount", they still kept a lot of the versatility of their smaller counterparts.
  • Great equatorial armillary The great equatorial armillary was built in 1585 and was one of Tychos most important instruments. It had a diameter of 3m and essentially, it was a simpler version of the armillary sphere.
  • Revolving quadrant The revolving quadrant was built in 1586, measured 1.6m in radius and was built out of wood. It used 8 different stars as "references" for Tycho and his students' calculations.
  • Revolving steel quadrant The revolving steel quadrant was built in 1588 and (surprisingly) it was constructed out of steel.
Tycho's outcome in favour of the later generations'

Even though Tycho Brahe conclusion of how the solar system was built, his work inspired people after his death that thanks to continuing his work finally could make the picture of our universe that we have today. We can use Kepler as an example. Tycho Brahe became interested in Keplers work, so he invited Kepler to be his assistant in Prague and help him calculate the orbits for the planets that Tycho saw in his observations. In 1600 he moved to Prague. After Tychos death, Kepler continued his work and published several important books such as Astronomia pars Optica in 1604 in which he treated atmospheric refraction, but also treated lenses and gave the modern explanation of the workings of the eye. With the spyglass, invented in 1610 he observed the satellites of Jupiter. Today Keplers work is used to calculate the orbits for artificial satellites and different bodies that are orbiting the sun. Keplers established a few laws:

  • The orbit of every planet is an ellipse with the sun at a focus
  • A line joining a planet and the sun sweeps out equal areas during equal intervals of time.
  • The square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit
These are the laws that Newton was able to use to establish universal gravitation Kepler only focused on the movement of the planets. Newton searched instead a description of the movement as a function of a couple of simple laws and connections. He created a model that described a complicated pattern of ellipses and their affection on each other, based on a few founding parameters and their meaning relation to each other.