Short answers, pulled from the story.
The first episode of Astro Boy 1963 TV series aired on New Year's Day 1963, which was a Tuesday. This broadcast marked the beginning of Japan's first popular animated television series that would eventually define anime for global audiences.
Astro Boy 1963 TV series delivered 193 episodes in total across four seasons until New Year's Eve 1966. The final episode aired on a Saturday evening closing out a run that had captivated the nation for three years.
Fred Ladd led the effort to adapt the series for American syndication starting the 12th of March 1963. NBC Enterprises announced they would begin broadcasting fifty-two episodes on the 7th of September 1963 in the United States.
Popularity declined because most television sets switched to color while the show remained black and white. Many storylines were deemed too violent or depressing for mainstream American audiences during the mid-1960s.
The original English masters from the 1963 series were destroyed in 1975 when Mushi Productions filed for bankruptcy. Right Stuf International later recovered surviving voice track elements combined with picture quality from Japanese negatives.