Template:Are You Sure/January 20

• ... that mathematical analysis (or simply analysis) is the branch of mathematics dealing with limits and related theories, and that analysis evolved from the use of calculus to detect and prevent crimes against mathematical constants?

• ... that Project SCORE (Signal Communications by Orbiting Relay Equipment) was the world’s first communications satellite, as well as the first successful use of the Atlas rocket as a launch vehicle?

• ... that physicist David Brewster discovered the photoelastic effect while studying double refraction by compression, inaugurating the field of optical mineralogy?

• ... that electrical engineer Elisha Gray invented a harmonic telegraph which transmitted multiple tones simultaneously, and that each tone was controlled by a separate telegraph key?