What is Tycho's star?

Answer 1

Tycho's Star is a supernova that was "discovered" by Danish astronomer Tycho Brahe in November of 1572 in the constellation of Cassiopeia. It was visible to the naked eye for 18 months, at its peak brilliance was brighter than the planet Venus and thus visible to the naked eye in broad daylight. This was the first "new star" noticed in the West in modern times. It confirmed Tycho in his suspicion that the heavens were not fixed and eternally unchanging. There seems to be some confusion as to whether the remnant of this supernova explosion -- visible today in a powerful telescope as a sphere of gas glowing at 50 million degrees Fahrenheit -- is indeed identical with Cassopeia A, the most powerful radio object in the sky after objects in our own solar system. Some sources on the net say Cassiopeia A is indeed the remnant of Tycho's Star, others that Cassiopeia A is the remnant of a supernova that exploded in or a little before 1680 and was briefly observed by Astronomer Royal John Flamsteed as a 6th magnitude star which he did not recognize as a "new star." I wish someone would clear up this discrepancy.

Answer 2

Tycho's Star, also known as Tycho Brahe's Supernova, is a remnant of a supernova explosion that occurred in 1572. It was one of the brightest supernovae observed from Earth and is located in the constellation Cassiopeia. Tycho's Star provided crucial evidence that stars could change, challenging the prevailing belief at the time that the cosmos was unchanging.