Simplify the following text for a Grade 11 native English-speaking person.
Original: Tycho Brahe ( 14 December 1546 â `` 24 October 1601 ) , born Tyge Ottesen Brahe , was a Danish nobleman known for his accurate and comprehensive astronomical and planetary observations .
Simplified: ' , born as Tyge Ottesen Brahe , ( lived December 14 1546 â `` October 24 1601 ) , was an astronomer from Denmark who built a big observatory called Uraniborg on a place called Hven in Denmark .