ashington, March 6 (ANI): A physicist has determined that if Galileo Galilei had followed the results of his observations to their logical conclusion, he should have backed the view that Earth didn't move, and that everything else circled around it and the Sun.
According to a report in Nature News, this is conclusion that Christopher Graney, a physicist at Jefferson Community and Technical College in Louisville, Kentucky, came to after reading manuscripts from another astronomer who was active in the late sixteenth and early seventeenth century, at the same time as Galileo.
Graney suggested in 2008 that Galileo's observations of stars were actually diffraction patterns called Airy disks - patterns of concentric circles that arise when light from a point source, such as a star, passes through a hole.
Diffraction hadn't been discovered in Galileo's time, so he was unaware of the phenomenon and believed what his eyes, or his telescope, were telling him and used the observations to estimate the size and distance of stars.
As a result, he got the distances of the stars too short by a factor of thousands.
After Graney realized that Airy disks had tricked Galileo, he decided to search for contemporaries of Galileo who might have seen similar things with their instruments.
"There had to be someone who had a good telescope other than Galileo," said Graney.
That someone was German astronomer Simon Marius, most famous for naming the moons of Jupiter (Io, Europa, Ganymede and Callisto) and claiming to have detected them just days before Galileo.
"Like Galileo, Marius mistook Airy disks as representing the stars themselves," said Graney.
"Whereas Galileo stuck to his Copernican system view, Marius's analysis of starry data led him to very different conclusions," said Graney, who made the finding after reading a German translation of Marius's book Mundus Iovialis (The Jovian World), published in 1614.
According to Graney, Marius concluded that his observations showed that the stars were too close to Earth to satisfy the Copernican world view, which says that the stars lie at a huge distance from Earth, and so would appear as starry pinpricks to any observer.
Marius said that the observation of the stars as disks confirmed the Tychonic system, which put Earth, unmoving, at the centre of the system with the Moon and Sun orbiting it.
The planets Mercury, Venus, Mars, Jupiter and Saturn all then orbit the Sun and the stars lie just beyond these planets in a fixed sphere.
"Marius's reasoning was more rigorous than Galileo's," said Graney. "In fact, Galileo's own data would lead to the same conclusion, had he followed it rigorously," he added. (ANI)