the rotation period of the Sun, the nature of the solar cycle, the existence of differential rotation and possible influences of the solar cycle on terrestrial climate. The basic observation is extremely simple. Any telescope can be arranged to project an image of the Sun onto a screen so that the positions of the spots can be indicated.
Styx was a Titan goddess in Greek mythology, daughter of the Titans Oceanus and Tethys, thus being one of the Oceanid sisters. She was the goddess of the River Styx, and wife to the Titan Pallas, with whom she had four children; Zelus, Nike, Kratos, and Bia. Styx fought on the side of Zeus and the Olympians during the Titanomachy, the great war between the Titans and the Olympians, the latter emerging victorious. To honour her, Zeus gave her name to the binding oath that was taken by the gods. The River Styx was the boundary between the realm of Earth and the Underworld. In its waters, the great hero Achilles was submerged when he was an infant by his mother Thetis, thus making him invincible; however, as she held him by his heel, that was the only spot on his body that was vulnerable.
The River Styx (meaning hate and detestation) formed the boundary between Earth and the Underworld . It circles the Underworld nine times. The rivers Styx, Phlegethon, Acheron and Cocytus all converge at the center of the underworld on a great marsh. The other important rivers of the underworld are Lethe and Eridanos, and Alpheus. The gods respected the Styx and swore binding oaths by it. Gods that did not follow through on such an oath had to drink from the river, causing them to lose their voices for nine years, then being exiled from the council of gods for nine years after that.