Ninety years ago on this date, Clyde Tombaugh discovered Pluto. It was, until 2006, regarded as the ninth planet in our solar system.
A new tyrannosaur species named Thanatotheristes, which means âreaper of death,â was the apex predator of its time, 79 million years ago in present day Alberta, Canada.
The European Southern Observatory’s Very Large Telescope is in northern Chile. Astronomers used it to capture the unprecedented dimming of Betelgeuse, a red supergiant star in the constellation of Orion. The new images show how theÂ apparent shape of this star is changing.