4 years
Astronomers are constantly finding new planets orbiting stars other than our sun. In 2005 astronomers discovered a new object, later named Eris, which almost become the tenth planet. The discussion of this object resulted in a new definition of a planet which excluded Eris.
New stars, different planetary designs, new celestial bodies, new moons, etc.
No. Most follow the new IAU definition of a planet which excludes Pluto.
No. The planets known in Kepler's time had been known for millennia. The first new planet to be dsicvoered by astronomers was Uranus in 1781, bout 150 years after Kepler died.
4 years
Astronomers are constantly finding new planets orbiting stars other than our sun. In 2005 astronomers discovered a new object, later named Eris, which almost become the tenth planet. The discussion of this object resulted in a new definition of a planet which excluded Eris.
Since the beginning of astronomy. Astronomers are ALWAYS looking for new things.
well back of Pluto there is a planet but they are still learning about it.
New stars, different planetary designs, new celestial bodies, new moons, etc.
Astronomers have decided that Pluto does not meet the definition of a planet.
No. Most follow the new IAU definition of a planet which excludes Pluto.
No. The planets known in Kepler's time had been known for millennia. The first new planet to be dsicvoered by astronomers was Uranus in 1781, bout 150 years after Kepler died.
Astronomers had noticed unexpected changes in the orbit of Uranus: the only explanation was another planet. Detailed study of the orbit of Uranus led to estimates about the size and location of Neptune.
Astronomers think Pluto is a dwarf planet. And they're right.
I want to discover a previously unknown planet with my new telescope.
No. It was categorised as a dwarf planet in 2006, but not all astronomers agree with that decision.