The exceptional performance of the PPR, combining high Isp and high thrust, holds the potential to revolutionize space exploration. The system’s high efficiency allows for manned missions to Mars to be completed within a mere two months.
Source: Pulsed plasma rocket (PPR): Shielded, fast transits for humans to Mars
Samuel Morse invented the telegraph, which was patented on June 20, 1840. He held patents for several other electromagnetic improvements, and was a fine artist as well. His political views were a non starter for me. He advocated for slavery, and was anti-immigration, among other things, but he did have some shining accomplishments in spite of that.
Here’s his Wikipedia article.
Born today (or the 20th, or 21st depends on where you look) Lloyd Augustus Hall. African American scientist who amassed 59 patents in food preservation.
Not much online about him, but here’s the Wikipedia article.
It was, also hard to find a picture. The drawing is from the first of only 2 that I found. Both are real small, and look like they come from some kind of yearbook, or company thing.
Couple more links:
African American Scientists Page
Web Archive of Inventor. org page