Many people would have observed the Supernova, however it's discovery was attributed to Tycho Brahe. That's why it is called "Tycho's supernova".
The most famous would be SN1572 or Tycho's supernova [See Link] It's appearance in the Milky Way was perhaps one of the two or three most important events in the history of astronomy. The "new star" helped to revise ancient models of the heavens and to inaugurate a tremendous revolution in astronomy.
It is the independent variable that is observed and the dependent that is observed.
No the word observed is not a noun. It is a past tense verb.
no
smell can not be measured but can be observed
yes they are observed by microscopes
trends best observed in?
Animals are often observed in the wild by remote cameras. This way they can be observed without humans disturbing them.
IT is observed on November 11th
A Grief Observed was created in 1961.
They were observed by primitive humanoids.
They should be observed because if they are not observed then people will not like you very much, and certain organizations will go after you.