This is just the beginning! Our collection holds over 300 years of history, including rare newspapers, obituaries, marriage records, birth records, and so much more—most of which you won’t find anywhere else!
Pluto Marks 25th Anniversary of Distant Discovery
The story recalls Clyde Tombaugh's 1930 discovery of Pluto, the ninth planet, after he captured a blinking image while scanning the sky at Lowell Observatory. It notes Pluto's distance, size, and orbital period, and mentions Tombaugh's later work and pursuit of small satellites in Earth’s gravitational field.
MENTIONED IN THIS ARTICLE
Washington
Pluto
Clyde Tombaugh
Solar Syst
National Geographic Society
Mercury
Venus
Mars
Jupiter
Saturn
Herschel
Neptune
Percival Lowell
Lowell Observatory
Flagstaff
Ariz
Tombaugh
Burdett
Kansas
W. M. Slipher
Lowell
Planet X
Dr. Lowell
International Mars Committee
White Sands Proving Grounds
New Mexico