QG

QUANTUM

GRAVIT Y

EVERYTHING YOU NEED TO KNOW ABOUT THE UNIVERSE THIS MONTH...

WWW.ASTRONOMY.COM 9

SNAPSHOT

Charles Messier

and comets

One of history’s comet lovers is

remembered for something else.

French astronomer Charles Messier

(1730–1817), who was born in Badonvil-

ler, Lorraine, and died in Paris, spent

much of his career targeting comets. Mess-

ier was lured into astronomy by his excite-

ment at seeing the Great Comet of 1744,

with its multiple tails, and by observations

of an annular eclipse of the Sun in 1748.

And it was the return of Halley’s Comet in

1759 that played a critical role in pushing

Messier forward into his studies and cata-

loging of comets and cometlike objects.

Not only was Messier greatly interested

in observing comets, but he also was

repeatedly irritated by running across

objects in his eyepieces that appeared like

comets but did not move relative to the

stars — fixed objects that could be con-

fused with comet discoveries. So he set

about creating a list of these celestial nui-

sances and published it in the 1771

Mémoires de l’ Académie, which was actu-

ally printed in 1774. This publication con-

tained a list of 45 objects, from the Crab

Nebula (M1) in Taurus to the Pleiades star

cluster (M45).

The so-called Messier catalog became

the gold standard for observers of star

clusters, nebulae, and galaxies (although

the nature of galaxies would not be known

until 1923), despite the fact that Messier

created it as a nuisance list of things to

avoid for potential comet discoverers.

— David J. Eicher

HOT BYTES >>

TRENDING

TO THE TOP

MAGNETIC CLOUD

The “Smith Cloud” has a

magnetic field that may

help it survive its future

Milky Way collision, say

scientists November 1 in

The Astrophysical Journal.

IDENTIFY A CAUSE

Research in the October

3 issue of Nature sug-

gests an ancient volcanic

eruption instead of an

impact formed the Eden

Patera Basin on Mars.

HEAVY METAL

Astronomers report in the

October 31 issue of Nature

their discovery that iron is

uniform across the Perseus

Galaxy Cluster, some 11

million light-years wide.

The Crab Nebula (M1) in Taurus became the first object Charles Messier listed in his catalog of non-cometary bodies that could

be confused with comets. Today, the so-called Messier catalog is the best listing of bright deep-sky objects for observers.

BOB fERA (CRAB NEBulA); Bill SAxTON, NRAO/Aui/NSf (MAGNETiC ClOud); NASA/JPl/GSfC (idENTify A CAuSE); CANAdA-fRANCE-HAWAii TElESCOPE/COEl

uM (HEAvy METAl)