Mirrors,
The Hubble space telescope first had one big shaped mirror, which made the images blury so they sent up astronaughts and replaced it with 4 8.2 meter flat mirrors making the pictures more clear!
the cridit goes to Galileo who discoverded it with his won telescope which he invented.
Because someone - Galileo Galilei - looked through the new wonder tool - the telescope - and saw four - he thought they were stars at first - but later realised they were moons of Jupiter.
Galileo discovered the four largest moons of Jupiter and that Venus showed phases like those of the moon.
The four largest moons of Jupiter are called the Galilean satellites, because they were discovered by Galileo when he first observed Jupiter with a telescope. Their names are: * Io * Europa * Callisto * Ganymede
The telescope was introduced to astronomy in 1609 by the great Italian scientistGalileo Galilee, who became the first man to see the craters of the moon, and who went on to discover sunspots, the four large moons of Jupiter, and the rings of Saturn. Galileo's telescope was similar to a pair of opera glasses in that it used an arrangement of glass lenses to magnify objects. This arrangement provided limited magnifications to 30 times for Galileo and a narrow field of view; Galileo could see no more than a quarter of the moon's face without repositioning his telescope.
reflectors
because he wanted to show the four largest moon
the cridit goes to Galileo who discoverded it with his won telescope which he invented.
He discovered that Saturn has rings and he discovered Jupiter's four largest moons.
The act of opening., An opening; an open space; a gap, cleft, or chasm; a passage perforated; a hole; as, an aperture in a wall., The diameter of the exposed part of the object glass of a telescope or other optical instrument; as, a telescope of four-inch aperture.
In Roman myths and legends, Ganymede was one of the many lovers of the chief god Jupiter. On first observing the four largest moons of Jupiter, Galileo gave the name Ganymede to the largest of them. (There are actually dozens of moons of Jupiter, but Galileo's telescope was only big enough to see the largest four.)
Because someone - Galileo Galilei - looked through the new wonder tool - the telescope - and saw four - he thought they were stars at first - but later realised they were moons of Jupiter.
The four largest moons - were named as a group after Galileo because of him being the first person to obseve them through his own invention - the telescope.
YerkesHale/PalomarHubbleGordon/Arecibo
Jupiter. The "Galilean" moons are the four largest moons, which are so large that Galileo was able to see them orbiting Jupiter even with his relatively modest telescope.
Galileo discovered the four largest moons of Jupiter and that Venus showed phases like those of the moon.
No planets orbit Jupiter. Jupiter is orbited by more than 60 moons, however. The four largest are visible from earth through a modest telescope. These four are known as the Galilean moons, as they were observed by Galileo 400 years ago. The largest of the four is Ganymede, a moon that is larger than the planet Mercury (though perhaps not quite as massive).