Skywatch - 2021 - 35

MESSIER: ANSIAUME / WIKIMEDIA
COMMONS / PUBLIC DOMAIN; SCORPIUS AND SAGITTARIUS: AKIRA FUJII

MOON PHASES
catalogs, based on naked-eye obseryes, Messier did discover comets as well
vations, had at most several thousand
- around 20, of which perhaps 14 were
Last
entries. With the advent and developsolo discoveries. But he's best remem1 | 5:11 p.m. EDT
Qtr
ment of the telescope,
bered for the catalog that
progressively fainter stars
bears his name.
New
9 | 9:17 p.m. EDT
Moon
were constantly added to
Fun with fuzzies.
ever-growing lists. The
July nights are perfect
First
17 | 6:11 a.m. EDT
currently orbiting Gaia
for checking out some of
Qtr
satellite will deliver data
the finest Messier objects.
Full
on a whopping 1 billion
Take the map on page 37
23 | 10:37 p.m. EDT
Moon
stars upon completion of
and hold it so that "Facing
the mission in 2022 -
South" is at the bottom.
Last
31 | 9:16 a.m. EDT
Qtr
and of course there will
See how many "M" objects
be a catalog.
there are in Scorpius and
S Charles Joseph Messier
Modern astronomical (1730-1817) is best known
Sagittarius? Go outside
catalogs cover everything for his catalog of fuzzy objects, and find a nice dark spot
Messier Marathon
imaginable. You name it, even if his primary occupation
with an unobstructed view
Taking
a crack at observing as
there's likely a dedicated
was searching for comets.
of the southern horizon
many
Messier
objects as possible
catalog somewhere. But
(the farther north you are,
during
the
course
of one night is
when did the tradition of recording
though, the lower on the horizon these
a
popular
activity
among
amaobjects other than stars arise?
constellations are going to be).
teur astronomers. At low northern
Enter Charles Messier. You may
Let's begin with the Teapot in Sagitlatitudes (particularly around 25°N),
have noticed that every star map in
tarius. Rising like a puﬀ of steam out
all Messier objects are visible from
this magazine features numerous
of its spout is the brightest patch of the
mid-March to early April. Go to the
objects labeled with an "M" followed
Milky Way, the Large Sagittarius Star
Astronomical League's instructions
by a number. French comet-hunter
Cloud, pointing the way toward our
and guidelines at https://is.gd/
Charles Messier is responsible for this.
galaxy's dust-obscured core. Above this
MessierMarathon for more.
Fellow French astronomer Josephpatch is a smaller star cloud: M24, also
Nicolas Delisle had calculated the
position of Halley's Comet for its
1758-59 return and hired Messier
to search for it. Messier spotted the
M17
M24
comet in January 1759, and, spurred
M23
on by this success, set out to find more
M25
comets. So as not to waste precious
observing time on stationary fuzzy
M20
M8
objects that clearly weren't comets,
M22
Antares
Messier started compiling a numM4
Large Sagittarius
bered list. The first two objects that he
Star Cloud
noted were the Crab Nebula (M1) and
a globular cluster in Aquarius (M2).
Te a p ot
M6
The discovery of a third fuzzy object,
a globular cluster in Canes Venatici
M7
SCORPIUS
(M3), likely prompted Messier to keep
Cat's
Eyes
a systematic listing of these objects.
S AG I T TA R I U S
The first edition of his catalog was
published in 1774 and included 45
objects, of which Messier himself
identified 17 (other astronomers also
contributed to this work). Today's catalog contains 110 entries of nebulae,
In summertime, the Milky Way rises from the southern horizon at an angle. The distinctive
star clusters, and galaxies, all prefaced
patterns of the Teapot asterism of Sagittarius and the constellation Scorpius are replete
by the letter "M" followed by a numwith Messier objects, including nebulae, open clusters, and globular clusters.
ber. And in case you were wondering,
SK Y WATCH 2021

https://www.is.gd/MessierMarathon.com https://www.is.gd/MessierMarathon.com

Skywatch - 2021

Table of Contents for the Digital Edition of Skywatch - 2021