WWW.ASTRONOMY.COM 41The Crab Nebula (M1) — the first entry that Charles Messier recorded in his
famous catalog of deep-sky objects — glows in this composite image taken by
NASA’s Hubble Space Telescope and Herschel Space Observatory (an infrared
telescope named after William Herschel, No. 5 on this list). ESA/HERSCHEL/PACS/MESS
KEY PROGRAMME SUPERNOVA REMNANT TEAM; NASA, ESA AND ALLISON LOLL/JEFF HESTER (ARIZONA STATE UNIVERSITY)Charles Messier
JUNE 26, 1730 –
APRIL 12, 1817
Charles Messier was a French
comet hunter who discovered 13
of those elusive objects. But that’s
not why he’s on this list. During
his comet searches, Messier often
came across diffuse objects that
didn’t change position against the
background stars the way that comets did. He made a list
of these objects so that he and other comet hunters could
quickly dismiss them and continue their searches. This
collection of nuisances was quickly adopted by amateur
astronomers as a catalog of alluring visual wonders. To this
day, the first deep-sky objects viewed by amateur astrono-
mers are almost always Messier objects. PORTRAIT: R. STOYAN ET AL., 200820
Clyde Tombaugh was only 24 years old when he discovered
Pluto. Before that, he had observed the sky with homebuilt
telescopes at his family’s farm in Burdette, Kansas. NMSU LIBRARY
ARCHIVES AND SPECIAL COLLECTIONSClyde William
Tomb aug h
FEB. 4, 1906 – JAN. 17, 1997
It would be absurd for me to leave an astronomer
who discovered a planet off this list. He’s also the one
person on this list that I knew well. As a Kansas farm
boy, Clyde Tombaugh built several telescopes and sent
sketches of planets to Lowell Observatory in Flagstaff,
Arizona. The detailed observations so impressed the
director, Vesto Slipher, that he hired Tombaugh and
gave him the task of searching for a planet beyond
Neptune, which culminated in the discovery of Pluto.
In that search — during which he scanned more than
90 million images — he also found several hundred
asteroids, a similar number of variable stars, and two
comets.19