On February 19:
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- 1878: Â Thomas Alva Edison patented a music player (the phonograph).
- 1968: The first nationwide broadcast of Mr. Roger’s Neighborhood aired on PBS.
- 2002: NASA’s Mars Odyssey spacecraft began using its thermal emission imaging system to map Mars.
- 2010: North Korea vowed today not to dismantle its nuclear program, not even in exchange for economic aid, as long as the United States continues a “hostile policy.”








