Event:
Astronomers identify a Trojan asteroid orbiting on the same path as the Earth around the Sun; it poses to danger to Earth because it sits in a gravitational 'sweet spot'
More Notable Events on July 28:
1945 Airplane crashes into the Empire State Building
1926 U.S. and Panamanian pact about safeguard of Panama Canal
1900 Hamburger created by Louis Lassing in Connecticut
1866 Metric system becomes a legal measurement system in U.S.
1858 Nadar takes 1st airborne photo, in a balloon
