cov14.qxd
13/10/2013
17:45
Page 1
Astronomical Calendar 2014
2
Astronomical Calendar 2014
CHARTS OF YEAR-LONG PATHS
The Moon each year travels 13.4 times around the sky, from west to east (right to left), through the 12 constellations of the zodiac, also Ophiuchus (it can touch Cetus, Orion, Auriga, Hydra, Sextans, Crater, Corvus, Scutum, Pegasus). The two nodes, where the path crosses the ecliptic, shift gradually westward. We show only the paths for January (thick line) and December (thin). The Moon itself is shown at the instants when it is New (black) and Full (white), at 5 times its true size. In each synodic month or lunation (29.5 days) the Moon goes from a New position all around the sky and on to the next New position; in each calendar month of 30 or 31 days its journey overlaps by a bit more. Eclipses happen at those New and Full Moons (the 6th or sometimes 5th of each kind) which are near enough to one of the nodes.
Charts for the major planets are plotted in ecliptic latitude and longitude. (Plotted equatorially they would take up much more vertical space.) The more familiar grid of equatorial coordinates (right ascension and declination) is also shown, curving in relation to the ecliptic system. The ecliptic itself is marked by dashes 2° long. Ticks mark the planets’ positions at the 1st, 11th, and 21st of each month. At the 1st is an open circle, sized for magnitude (brightness), so that the planet can be compared with the stars. On the scales of the maps, the planets’ disks would be only a few hundredths of a millimeter wide. The planets’ paths are black when in the evening sky (east of the Sun, left as seen from the northern hemisphere), gray in the morning sky (west or right of the Sun). Transition from black to gray is at conjunction with the Sun (for Mercury and Venus, inferior conjunction); transition from gray to black is at opposition (for Mercury and Venus, superior conjunction). For some of the planets, parts of the tracks for the neighboring years are included (in blue).
Coordinates of 2014
23
- 20
h
US ORNh C I R CAP 21
o
22
h
ecliptic latitude
Apr
IUS AR
U AQ
0
-10˚ -10
h
Coordinates of 2014
23
- 20
h
22
h
285 285˚
Mar
17 h
270 270˚
Feb Jan
S SAGIT TARIU
240 240˚
225˚ 225
Antares
255 255˚
LIBR
VIR GO
Nov
A
20
2
- 30
h
15 h
16 h
14 225˚ 225
18 h
195˚ 195
VIR G
O
A
Oct
h
-10˚ -10
180 180˚ +10 +10˚
eq ua to r
0˚
ec l ipt ic
Spic
a
15 h
16 h
17 h
12
h
210˚ 210
- 10 o LIBR
0˚
Sep
13
h
Antares
19h
180 180˚ +10 +10˚
eq ua to r
t a Oc
Nov
o
195˚ 195
Spic
240 240˚ SCOR PIUS
OPHIUCHU S
210˚ 210
- 10 o
Dec
S RNU RICO h P A C 1
o
18 h
19h
y lk Mia y W
h
0˚
S SAGIT TARIU
o
300˚ 300
Venus
255 255˚
Dec
h - 3200
315 315˚
al Fom
a
270 270˚
ec l ipt i c
Jan
360˚ ecliptic 345 345˚ longitude 330 330˚ 360 +10 +10˚ S E C S PI r to aut
u eq
285˚ 285
SCOR PIUS
ecliptic latitude
-10˚ -10
h
300˚ 300
Mercury
Mar
Apr
0
315 315˚
y lk Mia y W
360˚ ecliptic 345 345˚ longitude 330 330˚ 360 +10 +10˚ S E C r PIS S Feb to RIU ua q UA e Q A 0˚
14
13
h
12
h
h
-10˚ -10
Altair
Dec
-5 -5˚
- 20
-10 -10˚
l
- 30
h
o
1 Alt-15 22 -15˚ er f n2 Coordinates of 2014
144˚ 144
t ecliptic 140 140˚ longitude lhau a 20 Fo+m
ecliptic latitude
+4 4˚
135 135˚
Dec 1 Nov 1 p
Beeh
Sep 1
ive
o
-2˚ -2
c
y
w
l CER
g
15 h
s
b Pollux f 115 115˚ +25
1 4 ht
110˚ 110i
u
13
Aug 2
Aug 1
2013
o
d
e
z
+ 1 0 o30 -4 -4˚
Mebsuta
Mar 1 2013
Feb 1
9
Coordinates of 2014
w
248 248˚
f
m
ecliptic
245 245˚
30 m
h
a Acub k ens longitude
8
30
h
7
m
30 m
h
l 240˚ 240
235˚ 235
- 15
5˚ +5
230 230˚
Saturn
g h
+4 4˚
225˚ 225 224˚ 224 gx Almeisan 2 or Alhena
o
LIBR
x1 A
q
c
PIUS
3 + 3˚
+2 2˚
y
ecliptic latitude
r
opposition 2015 May 23
z
n
Dec 1
Jabbah
b
1˚ +1
w
opposition May 10
SCOR
w1 w2
0˚
Graffia
s
-20 l
-1˚ -1
16 Coordinates of 2014
Nov 1
Apr
Feb
Jan Oct
d
bba
Jun
Jul
2013
Aug
Sep
m
n Zub
en a elgenubi
o
e c l i p t i c
k
15
30 m i
Dschu
o
h
Sun-conjunction Nov 18
Mar
h
h
Tejat Propu
z
n m
k
Apr 1
Jan 5 opposition
Mekbuda
-15˚ -15
NGC2266
Jan 1
Wasat
h
96˚ 96
x o
0˚
100 100˚
May 1
Jun 1
ec l i p t i c
12
h
GEMINI
k
Jul 1
Jul 24 Sun-conjunction
+ 5˚ 5
-5˚ -5
w
m
Venus
q
Jun
105˚ 105
Mercury
h
+10˚ +10
-10˚ -10
16 h
h
Jupiter
Aug 18
A Ausster llus alis
o
17
h
120 120˚
CAN
d
Oct 1 +15
c 18
125 125˚
A Borseellus alis
2015 0˚
h
u1
LEO
y
19
130 130˚
o
Antares
180 180˚
+15 0 o +15˚
VIR GO
Jan Apr
Jul Sp ica
Aug
+1
SCORPIUS
f1S SAGIT TARIU
x
+2 2˚
n
20
h
Feb Mar
Sep
Oct y
h
195 195˚ opposition Apr 8
Aug 25
Nov
S RNU ICO R P CA
o
A
210 210˚
a t or
Saturn
Nov 11
ec l ipt i c
0˚
LIBR
Mars
eq u
ay
ecliptic latitude
Pluto
o
225˚ 225
M
- 10
240 240˚
ky i l
y
5 + 5˚
255 255˚
M
A
U AQ
+10 +10˚
270˚ 270
Wa
t hau mal o F Mercury and Venus stay near the Sun; so they start and end each year near its winter position 330˚ in Sagittarius. 315 315˚ ecliptic 300 300˚ longitude 285 285˚ 330 o +15 +15˚ S 0 U RI
3
Astronomical Calendar 2014 right ascension 21h Deneb
24h
+40 +40˚
18h
15h
12h
6h Capella
9h
+30 +30˚ PEGASUS
+20 +20˚
declination
Altair
PISCES Mar 0˚ 1 Sep 9 -10 -10˚
Jul 12
-20 AQUARIUS CAPRICORNUS -20˚
Jan 1
Jun 13
ec l ipt i c
0
135 135˚
+20
o
120˚ 120
105 105˚
Reg u
0˚
11
Pollux
-10˚ -10 180˚ 180 +10 +10˚
h
165 165˚
12
+1
h
0
9h
h
150 150˚
o
0˚
8
7
h
120˚ 120
o
Beeh ive Aug
h
6
105 105˚
20 20˚
h
10
h
9
ecliptic 19 19˚ longitude 18˚ 18
+8
7h
8h 16˚ 16
75˚ 75
S TAURU
5h
6h
0˚ +10 +10˚
Achernar Mercury
3
h
60˚ 60
45˚ 45
es Pleiad
ES ARI
2
u eq
h
14˚ 14
13˚ 13
4h 12˚ 12
1
h
-10˚ -10
15˚ 15
0˚ +10 +10˚
CES PIS
Venus
h
3
or a t
30˚ 30
Mira
Jun
Hyades
0˚
2
11˚ 11
h
0˚
May or t h ua q e 1
-10˚ -10
9˚
8˚
10˚ 10
Mira Sun-conjunction Apr 2
88
1 Aug
-1 -1˚
1 Sep
1 Oct
Feb 1
m
Jan 1
2013 ES
C
S PI
e
+6
Mar 1
1 Dec
1 Nov
Oct 7 opposition
73
30
Apr 1
May 1
Jun 1
Jul 1
2015
ecliptic latitude
A
Uranus
ec l i p t i c
S
U
ET
C
o
7777
-2˚ -2
+4 10
m
1
Coordinates of 2014 342 342˚ 1˚ +1
15˚ 15
CES PIS
Betelgeuse
8866
z
30˚ 30
ec l ipt ic
n Aldebara
15˚ 15
Proc yon
0˚
h
o + 3 0Betelgeuse
GEMINI
CAN CER h 17˚ 17
o
es Pleiad
ldebaran S ol Capella A TAURU Alg h h 5 4
lk y
71
e
45˚ 45
Canopus RIES
Jul
lus
ua to r
60˚ 60
May
90˚ 90
Proc yon Castor Pollux
Mi
eq
75˚ 75
Jun
Reg u
11
-20˚ -20
Apr
GEMINI
ER
135 135˚
+20 Sep
-10˚ -10
-10˚ -10
-30˚ -30
Jul
CAN C
10
+30 o
ec l ipt i c
lus
ua to r
90˚ 90
Castor
o
zz eq
0˚
l Algo
y
h
150 150˚
lk y Wa y
+1
+10˚ +10
-40˚ -40
Wa
165 165˚
12
+20˚ +20
SCORPIUS
-40˚ -40 180˚ 180 +10 +10˚
+30˚ +30
CETUS
Sirius
Capella
Antares
SAGITTARIUS
Fomalhaut
LIBRA
Nov 22 May 14
Dec 22
Regulus
Mi
-30 -30˚
+40˚ +40
Pleiades ARIES asnonular ecliplas r M ay 28 27 e n 16 Jun PISCES Ja A pr 29 Dec 6 Jul 26 N GEMINI n a Nov 6 Hyades Marew r a Betelgeuse 30 CANCER b Oct de l TAURUS 8 Procyon A Full ORION to lunatal eclip r Rigel se
25 VIRGO Aug 14 tial 4 2 parla Feb Sep so sre 16 SEXTANS eclip Mar 3 Oct 2 5 Spica Apro1tal HYDRA CRATER t ar lun se CORVUS p li ec
equa tor OPHIUCHUS
SCUTUM
Jan 3 0 Aug 1 0
0h
Castor Pollux M35
Beehive
LEO
Arcturus
+10 +10˚
3h
AURIGA
Vega
ecliptic 341 341˚ longitude 340˚ 340 67
339 339˚
o
May 15
Apr 14
Venus
+2
Mercury
m YZ
338˚ 338
h
50
h
337˚ 337
336 336˚
o
0 m 40
335 335˚
334 334˚
333˚ 333
332˚ 332
331˚ 331
330 330˚
S
U
I AR
U
ec l i p t i c
0˚ 78
ecliptic latitude
AQ
l
73
-8
Venus
Apr 12
Sun-conjunction Feb 23
Jun May 1 1 1 1 Jul Aug
o
2015
-1 -1˚
e
Feb Mar 1 1 1 Dec 1 1 Oct Nov
Apr 1 1 Sep Aug 29 opposition
Jan 1
2013 h 10 22
m
Neptune 58
h
-2˚ -2
o
40
45'' -19˚45 -19 open cluster
5m
right ascension
30
- 12
m
o
70
Ap r
41
Mar May
15'' -20˚15 -20
Jun
Jan
--------BB Sgr
Jul
36 or 36 Sgr
x1 45'' -20˚45 -20 -21˚ -21
Dec
Sun-onjunction Jan 1
29 Sgr
Nov
18h37m -19˚30' -19 30' -19˚45 -19 45'' -20˚ -20 -20˚15 -20 15''
Aug
-20˚30 -20 30''
SAGITTARIUS
Oct
-20˚45 -20 45'' -21˚ -21
or 37 Sgr
-21˚15 -21 15''
33 Sgr
-21˚30 -21 30''
Coo r d i n a t e s of 2 0 0 0
39 o planet The chart for dwarf Pluto is in equatorial coordinates, at scale 3 cm to 1°. Opposition falls in the middle of each retrograde loop, only about 1 or 2
40m 2013
Pluto
x2
15'' -21˚15 -21
42
45
2015
30'' -20˚30 -20
30'' -21˚30 -21
Feb
m
45m
opposition Jul 4
NGC6716 cluster
20
p Se
globular cluster
50m SAGITTARIUS
55m
-20˚ -20
declination
planetary nebula
p
Mar 22
m
19h
nebula
galaxy
Mercury
Coordinates of 2014 7m 30' -19˚30' -19
6 7 8 9 10 11 12 13 14
-10
22 m 50
days later each year. Plotted in blue are stars from the Tycho catalogue of the Hipparcos mission, which can be as faint as magnitude 11.5; those also plotted
in black are in the 9-times-smaller Hipparcos catalogue itself. Pluto’s magnitude is no higher than 14.1, so it is dimmer than the faintest stars on the chart.
30 28 28
Astronomical Calendar 2014
CA
di al r e eq c t i ui n on ox
I
i c
NI
2005 Nov 7 De200 c27 4
N CE R
ve
M GE
ES P I SC
S RIE
rn
e
A
S UR U TA
t i p cl
Ma rs nor rotati th p ona ole l
Spatial view of the four inner planets (Mercury and Venus for only the first three months of the year). On an imaginary sphere, 2 AU out, are shown the planes of the equator and ecliptic, and the boundaries of the zodiacal constellations. Globes for the planets at the start of each month are exaggerated 500 times in size; the Sun only 5 times. The path for a planet is drawn thicker when it is north of the ecliptic plane; gray when it is in the morning sky. Blue circles show the mean distances of the planets. Arrows from Earth to Mars are at the dates of several successive oppositions.
ecliptic north pole
l iona rotat le Earthorth po n
PLANET SPHERE-PICTURES
Nov
A QUA
Oct
Dec Dec
Sep 2010 Jan
Jan Mar
AN
Mar
Apr May
r8 n 14 Ap sitio 4 pr st 1 po 0 A e 2 p 14 ar o 20 ne
ar s
E
I CL
a ro t
OG R I V
Oct
TI
P
Jun
e uq
6 201 22 May
M
Mar
rt h
Jul
I CO R NU S
ITT GA
S
Ea
2018 Jul 27
C
Me r c u r y
u
201
P
Feb
s
3 2 Mar
L
Feb
n
Jan
CAP R
E
r to
Nov
Aug
Sun
Jan
e
e
a qu
De200 c 7 Feb24
V
O LE
RI US
2003 Aug 28
Jan
29
1
Aug
SU
IR
A
Jul
Jun
May
I L B AR
i c pt l i c e
c
i
i tp
C O
l c e
I
P
S
R
U
S
Ur
e
o
J
1
1987 l e y Ha l
er es
r Ma
oppositi
on Aug
29
s
PL A C PT I I L EC
opposition May 10
The planets from Earth (smallest ellipse) outward. Trajectories for this year are black (with stalks to the ecliptic plane at monthly intervals), whole orbits blue (stalks yearly). Each dash or gap in the opposition lines is 0.5 AU long. Ceres, Pluto, and Comet Halley are samples of the thousands of minor bodies that could be in the picture.
x
Jan p 5 C
1P
l
o in
on ti
ne tu
p
v
er i t op
na er
u eq
c re di
us
p
u
pp
O
e
Ha l l e y 1982
an
c
or
N
1P
at qu
t7
Sa t urn
A
-
-
1
U
NE
-
0 ro
t
au
q
e opp
osit ion
Jul 4
o ut Pl
no r t h
Astronomical Calendar 2014
g in t se
no
9
h h
eq
s Pleiade
Crab
CAN IS
hw
no
PE GA SU S a
s
u
q
oo
00 e g ++22 P o
M LU M33 GU N A TRI
++ 2200 oo
a
f
hh
S CE PIS
th
arter First Qnu8 Ja
ES ARI
e
C
ir
c
le
2233
t
hh
00 Uranus
e c l i p t i c hh
Proc INOR yon 88 hh
ua tor
Nath
Jupiter
G
re
t
s
t
HY DR A
M
PERSEUS
AURIGA
GEM INI
re
s
ce l e s t i a l
o o
S
ol Alg
TH
Full Jan 16
CA NC ER
++4400
NI
ZE
a
hh
11 11
ea s t
hh
oo
A ED M RO D N A
o o
Capella
C Po asto llu r x
0
he
O E L
++ 66 00
LACE RTA
l o o
+6 M0 i a ed m xy o dr ala An G
ALIS CAMELOPARD
LY NX
s e t t i ng
CEPHEUS
++ 8 0 0
o o
Li t
le
ua
Ga z el
y
p ip D
t le
rt
O LE R O IN M
s o f t he
EIA OP SSI A C
+4
ap
o o
CometISON C/2012 S1
o o
++ 88 00
W
k
er
o o
+ 88 00
o o
Le
rt
b Dene
SA R UR O IN M
e r p p D i ++6600
is lar Po
SA UR OR J MA
oo
e
a
we s t
s
e
s
t
Salt Lake City, Denver, Peoria, Philadelphia, Madrid, NaphThessaloniki, Ankara, Beijing
y
o o
00 re
Beeh ive
10
SKY DOMES
t
i
B i g
++4400
++22 Th
Re gu lus
SE XT AN S
DRA CO ++ 6 0 oo
r
in
CANES VENATICI
ng s i r i
sidereal time 5h
g
Evening sky for latitude 40° north about 10 PM at the 5th of the month, 9 PM at the 20th
rad i Quaant of dra n t i d met eor s
JANUARY
++8800
2
77
ran eba Ald
Betelgeuse h h
11
es Hyad
33
h
66
MONO CEROS
h h
44
55 hh
h h
o r equa t
ce l es t i a l
hh
hh
Mira
S CETU
a
y
ORION
22
TAURUS
W
Rigel
Sirius
y
(movem e t of sk in 1 hn our) y r
k
i s i ng
y ent of sk (movem hour) 1 in g t i n s e t
ERIDANUS
-- 2200 oo
l
CANIS
LEPUS
so
M
i
MAJOR
FORNAX
th
ea
0
u so
s t
1 2 3 4 5
COLUMBA
PUPPIS
-- 4400 oo
open cluster nebula planetary nebula globular cluster
n s e t t i ng
h
GEMINI
Jupiter
Mars
4 rn JJaann 224rrtteerr turn SSaatu Quuaa LLaasstt Q
rrss Maa M
A RA DR YD HY H
PIS CE S
AND ROM EDA
S IE AR
IGA AUR
S RU TAU
CANCER
O VIRGO VIRG
LIBR LI BRA A
PER SEU S
Jupit er
F Jan ull 16
GEM INI
A AURIG
EEIIAA OPP SSIIO CCAASS
ZE
LE O
TH
TH
O EO LE L
NI
S EU RS E P
Jan 16 Full
OPPH O HIIU UC CH HU USS
SCORPI SCO RPIUS US
U M RS AJ A OR
EERR NNCC A A CC
BOÖT BO ÖT TE TE ES ES SS
URSA MINOR
RA LY
AA RRSS ORR U AAJJO U M M
NN II
SSAAG GIITTTT AARRIIU USS
Midnight sky for 40° north
ES ÖT BO
S NU C YG
URRSA U SA MIN M INO ORR
HEE H RRC CU ULL EESS
r
galaxy
z
s ou t h
PERSEU PER SEUSS
1 hour before sunrise
o
i
CASSIOPEIA
Pre-dawn sky for 40° north
an 16 16 an
t
o
r i s i ng
AAQ QUU IILLAA
t
hw
s
CAELUM
ZE
ma g n i t u d e s
u
—1
e
N ORIO
NUS ERIDA
HYDR A CANIS MAJOR
Jan 16
Astronomical Calendar 2014
US GN
T AU R U S
CY
Jupi
I EM I N G y CER CAN gh t s k
O
SA R UR NO I M
m
L
Ven u
Mar s
cu r y
er
V I RG O
PEG ASU S
ES
IO PE IA
C
CA SS
S
y
ke
u at
S
.
HI
UCH
US
SOLAR SYSTEM PLAN
Pluto
OP
S IU R S AG I T T A
CA
P
S NU
R
Solar System Plan
aphelion perihelion node opposition greatest elongation conjunction with Sun conjunction of planets (in longitude)
DA ME RO D N
A
ARIES
TAURUS
First Q u Jan 8arter
The SOLAR-SYSTEM PLANS are views from the north ecliptic pole. The courses of the four inner planets are shown by curving arrows. (Lines point to the outer planets, which are much too far away to show at this scale.) Where a planet is in or north of the ecliptic plane its arrow is thicker. The rest of each orbit is indicated by dots 5 days apart (black where the planet has already passed in this year). The Moon’s illuminated side—hugely exaggerated in size and distance from Earth—is shown at its New and Full positions. The Sun is also vastly too large. The white side of the diagram is the sky toward which we face about 10 p.m. in the middle of the month. Around the edge are the directions to the zodiacal constellations as seen from Earth, not Sun, at the middle of the month. Some marked events are explained in the key underneath, and at their dates in the calendar.
PISCES
Ura
nus
TH
ZE
OR
E
rn
IC
ZE
I
sk
E
g
ne
1P 2
R JO A
SA
M
R
ORION
NI
Ecuador, mouth of Amazon, Gabon, Uganda, Kenya, Sumatra, Borneo, IA E Kiribati, P O SI Galápagos S A
PERSEUS
AURIGA
TAURUS
ERIDANUS CANIS MAJOR
D
ds t i
U
C
CANCER
HY
an
Evening sky for the equator (latitude 0°)
ptu
nc
A
Jupiter Jan 16 Full
M
Ne
S CO
RA
dr
BR L I
ERIDANUS
GEMINI
us
Uran
2.0
CANIS MAJOR
LE O
31
nits Sun al u.5 c i 0 nom stro1.0 a f le o sca 1.5
TAURUS ORION
ua Q
Uranus
11
ES
ARI
Jupite Jan r Full 16
P
4
ter Quar First Jan 8
s 24
A
S
EU PERS
AURIGA
P
in
5
INI
S CE IS
3
Ear th
y sk
TH
N
GEM CA NC ER
A ED M RO D
S EU RS PE
ES
v
n
i
e
AR I
e
n id
mo r n ing
SA UR OR J MA
O LE
NI
3
2014 Jan
ter
Vancouver, Winnipeg, Newfoundland, Plymouth, Brussels, Frankfurt, Prague, Kiev, Mongolia, Sakhalin
AQU A R I U S
Evening sky for latitude 50° north
LA
The SKY DOMES are what you see as you lie on your back with your feet pointing south. For more positions of the Moon and planets, see the <Zodiac charts>.z
CA RI NA
VE
Evening sky for latitude 35° south
mid Chile, Buenos Aires, Uruguay, Cape Town, Canberra, Auckland
Jan 16
PERSEUS
AURIGA GEMINI
LEO
ARIES
Jupiter
ER
CANC
Jan Full
TAURUS
16
Fir st Q Jan uar 8 ter
ORION
nu ra
U
ZE
NI
s
A
CES
TH
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CANISR MAJO
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The Milky Way on January evenings crosses overhead diagonally from southeast to northwest. (As seen from mid-northern latitudes of the Earth, that is.) We call this reach of it the Winter Milky Way, though more correctly it’s the north-hemisphere’s winter early-night Milky Way. (Rivers are divided into “reaches,” such as the Greenwich Reach of the Thames. Many cultures have seen the Milky Way as a river.) What is now above the horizon is the outer half of the Milky Way. The direction straight outward from our galaxy’s center is just east of the star Nath (Beta Tauri), near the zenith at this time. Because we are looking through the galaxy’s disk toward the nearest part of its rim, we see the narrowest and dimmest part of the band. The haze of stars is thinner than in the opposite direction. Yet this part of the band is the richest in very bright individual stars! The reason is that we are looking out through the nearest spiral arm, on whose inner edge we are, and in which the birth of massive stars is going on. Seven of these heroic stars form the most famous constellation, Orion, now confronting us on the meridian, the nave of the sky. This is the Orion Hour (“The Heavens by Hours,” Astronomical Calendar 2012, page 76) January is a month when nights start early (good for stargazing) but are coldest; when the Milky Way is highest, yet glows dimmest, yet so obviously glitters with stars that it is probably the month when non-stargazers are most often struck by them.
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Astronomical Calendar 2014
January Januarius (or more fully Januarius mensis) was the month of Janus, Roman god of beginnings and of doorways. Statues showed him with another face on the back of his head. Pre-Christian England had its own month-names. According to the scholarly monk Bede in his De Temporum Ratione, “On the Reckoning of Times,” 725 AD, December and January were covered by one name, Giuli. This must be related to “Yule” (geol in AngloSaxon, similar words in other Germanic languages, origin unknown), a 12-day festival, later transformed into the Twelve Days of Christmas. Christianity, with literature written in Latin, brought in the names used by the Romans; in medieval English these took on variant forms, often influenced by French.
Some such forms survive in dialects, such as Janiveer and Janwar. Since the Renaissance we have returned to anglicized forms of the Latin names. The calendar now used in most of the world is called the Gregorian. In 1582 (or later in many countries) it replaced the Julian calendar, which added a leap day at the end of February in every 4th year. This was slightly too many, so that the average year was slightly too long. The two calendars are now out of step by 13 days, so that Julian Jan. 1 falls on our Jan. 14. The divergence will next be increased by the Julian leap day in 2100, so that Julian 2101 Jan. 1 will fall on Gregorian Jan. 15. The Julian calendar is still used for some religious purposes. Even the dates of the old Roman calendar are given in some almanacs: this Julian Jan. 1 is the first
Earth and Sun in January In January our planet is traveling around the part of its orbit which, seen from the Sun, is in the direction of the constellations Taurus and Gemini. So we see the Sun in the opposite direction, in Sagittarius and Capricornus. Facing outward at midnight, we see in the middle of the sky the stars of Taurus and Gemini, and around them their neighbors such as Orion and Auriga. This part of Earth’s orbit is the closest in toward the Sun, though not by much. And Earth’s north pole is still tilted away from the Sun, nearly as much as it was in December, so the northern hemisphere is receiving sunlight for less time and at lower angles.
day of the Roman year 2767 A.U.C. or ab urbe condita, “from the city founded”—from the legendary date of the founding of Rome in perhaps 753 BC. Jan. 7, which is 13 days after Dec. 25, is Christmas for the Eastern Orthodox church, or at least for “Old Calendarists” still using the Julian calendar. In the 19th century it fell 12 days after Christmas, on Jan. 6, so there is some confusion with the Twelve Days of Christmas, ending on Epiphany, Jan. 6, the Adoration of the Magi. equinox Sep 22
solstice Dec 21 Sun
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solstice Jun 21
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Winter already waning? The solstice—shortest day for Earth’s northern hemisphere, longest for the southern—was on 2013 Dec. 21. However, in another sense midwinter passed even earlier than that. For places at latitude 40° north, the earliest sunset was on Dec. 7, and the latest sunrise comes on Jan. 4. (For higher latitudes these dates get closer to the solstice, and vice versa; for example at latitude 60° north they are Dec. 16 and Dec. 27.) Why do earliest sunset and latest sunrise not coincide with the shortest day? They do, if we measure hours from true solar midnight and noon. But our clocks use mean solar time, as if noons were a fixed distance apart; which they are not, because of the slightly changing speed of Earth in its elliptical orbit. Because most of us are asleep at sunrise but up when the Sun sets, days seem to start getting longer after the earliest-sunset date (though only by seconds, till mid January). In this sense winter seems already half over—a cheerful thought, even though the coldest weather is probably yet to come!
Earth at the four cardinal points in its orbit, the solstices and equinoxes. The Sun’s size is exaggerated 20 times, the Earth’s 1500 times. At the December solstice the north pole is tipped at its maximum angle of 23.4° away from the Sun; in January it is starting toward the March situation of being tipped sideways instead of away.
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The Sun enters Capricornus on Jan. 19. That is, it crosses the Sagittarius-Capricornus boundary as officially defined in astronomy. (These elaborate lines, giving definition to the traditional areas of the 88 constellations, were partly worked out by Benjamin Gould in 1875 and completed by Eugène Delporte in 1930.) Because of precession—the shifting westward, at about 14° per thousand years, of the point where the Sun is at the March equinox—the longitudes of these constellation-boundary-crossing-points from the equinox point slowly increase; so their dates become, each year, a few hours later. According to the ancient system still used by astrology, which divides the circle of the sky into 12 equal 30°wide “signs,” fixed in relation to the moving March equinox, the Sun enters, on Jan. 20, the sign Aquarius, since its longitude is 300°. This system is now about two thousand years out of date with respect to the Sun’s actual direction among the stars. Astronomically the Sun has only just entered the next constellation back.
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Earth is at perihelion, the innermost point of its slightly elliptical orbit around Circle with radius 1 AU hêlios, the Sun, on Jan. 4. centered on the Sun, blue; The average distance between the slightly elliptical orbit of centers of Sun and Earth (known as the Earth, black. The dot for astronomical unit or AU) is 149,597,871 the Sun is true to scale; kilometers (92,955,807 miles). The the dot for Earth is exageccentricity of the orbit is only 0.017. gerated 100 times in size! This means that at perihelion the SunEarth distance is 1.7 percent less, or about 0.983 AU. Mainly because of the swinging of Earth and Moon around their barycenter or common center of mass, the minimum SunEarth distance varies: up to about 0.00005 AU or 7,500 km greater (near New Moon) or smaller (near Full Moon). This year it is 0.983,335 AU (about 147,104,800 km). And the date of perihelion varies, from about Jan. 1 22h near Last Quarter Moon (when the Moon is ahead of us) as in 1989, to Jan. 5 8h near First Quarter as in 2020. The relatively slight variation in distance from the Sun has little effect on warmth and is not the cause of our seasons. Indeed, we happen to be nearest to the Sun in the middle of our north-hemisphere winter. Contrast the effect on Mars (Jan. 3).
Earth on Jan. 4 (at 15h Universal Time, which is 3 PM for Britain, 10 AM for eastern North America, 9 AM for the Central time zone, 7 AM for California). The thick arrow is a “rail” along which the planet is riding in its orbit at its speed of about 2,574,000 km per day; each visible piece of the arrow is a distance the Earth advances in one minute (around 1,800 km). An arrow above the equator shows how far Earth rotates in one hour (15°) around its axis (shown by a pole at the north pole). A trident represents the vertical beam of sunlight, striking where the Sun is at the zenith at noon—now slightly north of the Tropic of Capricorn. In January, northern latitudes are beginning to have slightly longer days with slightly less-low sunlight; the north pole still never gets in view of the Sun.
The Sun’s journey in January, plotted ecliptically. The black line is the Sun’s track, keeping to the ecliptic. The Sun itself is shown at true scale at 0h Universal Time of each day, and at twice scale on each 10th day. ecliptic longitude 300˚ 300 270˚ 270
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Earth and Moon are drawn at true scale for their distance apart. The barycenter, or center of mass, of the Earth-Moon system is about 4640 kilometers from the center of the 6378-km-radius Earth. It keeps moving through the solid matter of the rotating Earth. It takes a smooth orbit around the Sun. Earth and Moon revolve around their barycenter. So Earth is pushed slightly outward at New Moon, forward at First Quarter, inward at Full Moon, backward at Last Quarter. So the truer orbit of Earth itself is a slightly wavy ellipse.
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Astronomical Calendar 2014
January events
í &#x2019; Moon New. Beginning of lunation 1126. Moon 1.9° N. of Pluto (only about 4° from the Sun). Pluto at conjunction with the Sun. Moon 6.6° N. of Mercury (only about 4° from the Sun). Moon at perigee (only 9.8 hours after New Moon); distance 55.96 Earth-radii. Almost as near as on Aug. 10. 2 Thu. ( 3) Moon 1.5° W.N.W. of asteroid 6 Hebe (only about 11° from the Sun). (11) Moon 2.0° N.N.W. of Venus (15° from Sun in evening sky). 3 Fri. ( 0) Mars at west quadrature. ( 0) Mars at aphelion, 1.6661 AU from the Sun. ( 2) C/2012 S1 ISON at opposition. <COMETS> (19:35) Quadrantid meteors. <METEORS> 4 SAT. Latest sunrise (7:22 AM) at latitude 40° north. (12) Earth at perihelion, 0.98330 AU from Sun (23) Moon 5.1° N.N.W. of Neptune (49° from Sun in evening sky). 5 SUN. (21) Jupiter at opposition. 7 Tue. Eastern Orthodox Christmas. ( 8) C/2012 S1 ISON nearest to north celestial pole. <COMETS> (12) Moon 2.9° N.N.W. of Uranus (82° from Sun in evening sky). (14) Venus 6.4° N. of Mercury (only about 7° from the Sun). 8 Wed. ( 3:39) í &#x2018; First Quarter Moon. 9 Thu. ( 9) P/1998 U3 Jaeger nearest. <COMETS> (11:26) Moon at descending node (longitude 34.8°). 11 SAT. ( 6) Mercury at greatest latitude south of the ecliptic plane (â&#x20AC;&#x201D;7.0°). (12) Venus at inferior conjunction with the Sun, 0.266 AU from the Earth and 5.19° north of the Sun. (12) Moon 6.2° S. of the Pleiades (about 128° from Sun in evening sky). 12 SUN. ( 9) Moon 2.5° N. of Aldebaran (138° from Sun in evening sky). 14 Tue. This day is Jan. 1 in the Julian calendar. ( 4) Moon 5.1° S. of M35 cluster (158° from Sun in evening sky). 1 Wed. (11:14) (12) (14) (14) (21:03)
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15 Wed. ( 5) (17)
Moon 4.9° S. of Jupiter (about 168° from Sun in evening sky). Moon 14.9° S. of Castor (173° and 169° from Sun in the midnight sky). (23) Moon 11.6° S. of Pollux (about 173° from Sun in the midnight sky). 16 Thu. ( 2) Moon at apogee; distance 63.74 Earth-radii. Almost as far as on July 28. ( 4:52) í &#x201D; Full Moon. 17 Fri. ( 4) Moon 6.3° S.S.W. of Beehive Cluster (about 168° from Sun in morning sky). 19 SUN. ( 2) Moon 4.9° S.S.W. of Regulus (about 148° from Sun in morning sky). í &#x201C; Sun enters Capricornus, at longitude 299.64° on the ecliptic. (19) 20 Mon. ( 4) Sun enters the astrological sign Aquarius, i.e. its longitude is 300°. (16) 209P LINEAR at opposition. <COMETS> 23 Thu. ( 4) Moon 3.5° S.S.W. of Mars (about 102° from Sun in morning sky). (10) Moon 1.3° N.N.E. of Spica (99° from Sun in morning sky). 24 Fri. ( 2:58) Moon at ascending node (longitude 212.8°). ( 2) Venus at perihelion, 0.7185 AU from the Sun. ( 5:20) í ? Last Quarter Moon. 25 SAT. (14) Moon 0.57° S. of Saturn (73° from Sun in morning sky). <OCCULTATIONS> 26 SUN. (19) Moon 7.6° N. of Antares (57° from Sun in morning sky). 29 Wed. ( 0) Moon 2.0° N. of Pluto (27° from Sun in morning sky). ( 3) Moon 2.2° S. of Venus (26° from Sun in morning sky). ( 5) Moon, Venus, and Pluto within circle of diameter 4.51°; 26° west of the Sun. 30 Thu. ( 8) Mercury at ascending node through the ecliptic plane. ( 9:52) Moon at perigee (only 11.8 hours before New Moon); distance 55.99 Earth-radii. (21:39) í &#x2019; Moon New. Beginning of lunation 1127. 31 Fri. (10) Mercury at greatest elongation east, 18.4° from the Sun. (19) Venus stationary in right ascension; resumes direct (eastward) motion. The stationary moment in longitude is 2 hours later.
Hours are given in Universal Time (UT). Hawaii Standard Time = UT-10 Alaska ST = UT-9 Pacffic ST = UT-8 Mountain ST = UT-7 Central ST = UT-6 For ECLIPSES, OCCULTATIONS, ASTEROIDS, COMETS, and METEORS refer to their sections.
Read this along with the Zodiac Charts, and the other general charts and diagrams at the end of the book. ward as seen from our northern hemisphereâ&#x20AC;&#x201D;instead of The planets in January its usual direct or eastward motion. Starting from the Sun and scanning eastward (leftward, Jupiter takes 12 years to go around the Sun (more in our northern hemisphere), we find the planets exactly 11.86). This is its sidereal (â&#x20AC;&#x153;starryâ&#x20AC;?) period, the arranged as follows. <Zodiac charts> time it takes to come back to the same place on the celestial map. So each year it advances about 30°, Mercury is at first much too close to the Sun to be seen, spending roughly a year in each of the 12 zodiacal conthen climbs to easternmost elongation on Jan. 31. stellations. This smallest and fastest-moving major planet (only So the Earth takes a bit more than 13 months to 1.4 times wider than the Moon) orbits the Sun 4.15 times catch up and again pass Jupiter. This is the planetâ&#x20AC;&#x2122;s a year, but from our moving viewpoint it appears to go synodic (â&#x20AC;&#x153;conjunctionalâ&#x20AC;?) or seen-from-Earth period. The around only 3.15 times. Each year it makes 3 or 3-andoppositions of Jupiter advance from January to February a-bit swings into our morning sky and as many into the and so on, also moving later in each month, until a evening sky. These â&#x20AC;&#x153;apparitionsâ&#x20AC;? are of markedly month is skipped; and the time comes when a year is unequal characters, because of Mercuryâ&#x20AC;&#x2122;s eccentric orbit skipped. 2013 was one of those oppositionless years, and the varying angles at which we view it from different so now the cycle starts again with opposition in early parts of our own orbit, and from different latitudes on the January. Earth. It has to take place in Gemini, opposite to the Sunâ&#x20AC;&#x2122;s This yearâ&#x20AC;&#x2122;s first excursion is a fairly favorable one down-south January home in Sagittarius. December and into the evening sky. Mercury passed behind the Sun January oppositions have the advantage (for north-hemi(was at superior conjunction) on 2013 Dec. 29; so at the sphere people) that they are in the northernmost part of first sunsets of January it is still down at the horizon, the planetâ&#x20AC;&#x2122;s 12-year journey. deep in Sun-glare. But, contrary to Venus, it is climbing Jupiter at this opposition is just over 4 AU from us. upward from day to day, and by about Jan. 12 its tiny Actually the instant of nearest approach is 27 hours earlispark may become findable. On Jan. 31 it reaches its er than the instant of opposition, because of the slight greatest angular distance (elongation) from the Sun, of outward curvature of this part of the orbit, and the Earth18.4°. And since, for our northern latitudes, it is posiJupiter distance is 4.21 AU (629,800,000 km). This is tioned not too far from vertically above the Sun, it reachnot the very nearest the planet can be to us; it was just es a respectable altitude of about 16° above the sunset under 4 AU away at the oppositions of 2010 Sep. and horizon. Not the greatest, because it is in a part of its 2011 Oct. It can be nearly 4.5 AU away, as in 2005 Apr. orbit rather near in to the Sun (perihelion comes on Feb. It shines at a peak magnitude of â&#x20AC;&#x201D;2.7, and its equa3). torial diameter in the telescope is 45â&#x20AC;ł. Moon-glare does not spoil the sky (the Moon being New 4½ days before Farther up into the evening sky are Neptune and opposition. Now is the best time to examine the great Uranus, in Aquarius and Pisces; remote planets that are planet, looking for its cloud bands and its satellites. not for finding with the naked eye. Telescopic hunting for them is best left till nearer the times of their oppositions, Then Mars, over on the morning side and half way down in August and October. toward the sunrise. Mars is at west quadrature on Jan. 3. This means Then Jupiter, high north in Gemini, in the midnight sky, that it is 90° west of the Sun (as seen from Earth), in the at opposition on Jan. 5. This is Jupiterâ&#x20AC;&#x2122;s month. middle of the morning sky. It rises about midnight, and â&#x20AC;&#x153;Oppositionâ&#x20AC;? is when a moving body is in the direcyouâ&#x20AC;&#x2122;d have to train your telescope on it between then tion opposite to that of the Sunâ&#x20AC;&#x201D;outward for us at midand dawn. It is in Virgo, northwest of the bright star night. It is about at its highest and longest in the sky, Spica. about at its nearest to us, thus appearing largest and At quadrature, the shadowed area on the western brightest. The best weeks or months for observing it are (right) side of the planetâ&#x20AC;&#x2122;s disk is at its relative widest. centered on its opposition. During this time, because we The disk is as yet small, slightly wider than its average in our shorter orbit are overtaking it on the inside, the size: Mars is drawing nearer, toward its opposition in planet appears to move backward: its motion across the April. <Mars disk diagrams> starry background is retrogradeâ&#x20AC;&#x201D;westward. or rightAt virtually the same instant as west quadrature (13 minutes later!) Mars is at aphelion. Itâ&#x20AC;&#x2122;s only a coinci-
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dence that these events (one geocentric and the other heliocentric) are, this year, close together, and also close to the Jan. 4 perihelion of Earth. Earthâ&#x20AC;&#x2122;s perihelion and aphelion have little climatic effect; contrast the effect on Mars at its solstice on Feb. 15. Usually Mars in its 2.13-year orbit has only one of these â&#x20AC;&#x153;heliaâ&#x20AC;? events in a year, but because the aphelion is so early in this year, perihelion will fit in before the end of the year, on Dec. 12. Then Saturn, lower again toward the Sun and rising between 4 and 5½ hours before it. Pluto starts the year behind the Sun (3° north of it), moving into the morning sky. It didnâ&#x20AC;&#x2122;t experience this Sun-conjunction event at all in 2013, because the last time was on 2012 Dec. 30. Venus is at inferior conjunction with the Sun on Jan. 11. On the first few evenings of the year, Venus may be discerned low over the setting Sun, only 17° up-left (east) from it on Jan. 1, dropping closer each evening. If, just after the Sun has set (donâ&#x20AC;&#x2122;t try before!), you can find the bright spot in your binoculars, it appears as a crescent relatively huge in lengthâ&#x20AC;&#x201D;almost a minute of arcâ&#x20AC;&#x201D;but extremely slender. For you are seeing it as it is about to whirl between us and the Sun. It doesnâ&#x20AC;&#x2122;t do so exactly, but passes (on Jan. 11) 5° to the Sunâ&#x20AC;&#x2122;s north. So it might still be glimpsed there (but more probably not!) immediately after sunset on Jan. 10 and also immediately before sunrise on Jan. 11 and 12. On other occasions of this inferior conjunction, happening at other points in Venusâ&#x20AC;&#x2122;s 3°-tilted orbit, it can appear more than 8° north of the Sun (as in 2009 and 2017) or nearly 8° south (as in 2007 and 2015) or actually cross the Sunâ&#x20AC;&#x2122;s disk (as in the rare â&#x20AC;&#x153;transitsâ&#x20AC;? of 2004 and 2012, not to happen again till 2117). At Sun-conjunction Venus is only 0.268 AU (about 40,000,000 km) from us. It now moves into the morning sky, and may be found with difficulty just above the about-to-rise Sun on Jan. 14 and then a little more easily each morning. And its long slender crescent gets shorter and fatter each day as it circles away from us. And it spends most of the rest of the year in the morning sky, not passing around behind the Sun (superior conjunction) till Oct. 25. In Venusâ&#x20AC;&#x2122;s 8-year cycle, this (like 2006 and 2022) is the year when few but early-risers will see it; the year that is almost deprived of the great Evening Star.\
Astronomical Calendar 2014 Because the descending node is on a north-sloping part of the ecliptic, the track goes on to arch well south of the northern arch of the ecliptic in Taurus; and similarly it lies north of the ecliptic’s southern dip in Sagittarius. In other words the overall track is rather flat (compared with other years when it is “hilly”); the Moon does not venture extremely north or south. It is northernmost this year on Jan. 13, and southernmost on Jan. 27, because the flatness effect is increasing. Having hopped over the Sun on Jan. 1, the Moon descends on Jan. 9; re-ascends on Jan. 24, in time to clear north of the Sun again at the Jan. 31 New Moon. The path steers among the stars and planets that lie near the ecliptic: south of the Pleiades, Jupiter, Pollux, Regulus, Mars, north of Aldebaran, Spica, Antares—and in front of Saturn. After the month’s second New Moon comes a second Young Moon. On Jan. 31, the ecliptic’s angle from the horizon is favorably steeper, and the Moon has passed farther north of the Sun, but for Europe and North America the timing is about 10 hours closer to New Moon; the first sighting may be farther west or on a later evening.
glimpse the very slim crescent, facing down to where the Sun has just set, only 30 hours “old,” just above Venus before they both follow the Sun down. It will be a little higher, thus easier to see, but 5 hours older, at sundown in the eastern US. And it will be progressively easier to spot, and older, farther west or on later evenings. The Moon gets away from the Sun and broadens till on the night of Jan. 8 half its Earthward face is sunlit, at First Quarter. (Or Half Moon as it is popularly called; either could fit if you refer to area, but quarter can also refer to time, and the third phase, Last Quarter, could hardly be called Last Half.) As it rounds its orbit, the Moon is now following Earth in their common orbit around the Sun; the Moon is where the Earth was about 3½ hours ago. Half way between New Moons and perigees, the Moon is almost simultaneously Full and at apogee (its most distant) on Jan. 16, so this Full Moon in Gemini appears smaller than usual. But this is scarcely noticeable: the distance-differences at apogee are much smaller than those at perigee. It’s hard to tell by looking at it when the Moon is exactly opposite to the Sun. Has the softness passed from the left edge to the right? So in a looser sense the Moon is considered Full for perhaps three days.
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The Moon’s path: Its orbit slants at 5° across the ecliptic plane, so its path during each month is fixed by the two nodes (Latin nodus, “knot”), the points where it “descends” southward and “ascends” northward through the ecliptic. The nodes continually precess—migrate backward (westward)—at about 19° a year (migrating all around in 18.61 years). This year, the descending node starts in western Aries, the opposite ascending node in eastern Virgo. <Moon chart>
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In these horizon-based (altazimuth) scenes, the location is latitude 40° north and longitude 0°, unless otherwise noted. The scale is 4 mm to X 1°, or, for enlarged views of smaller N areas, 1 cm to 1°; you can tell LY or larger scale by the size of the whether a picture is on the smaller Moon, which is drawn true to scale.
o o Jan n 14
OR
IO N
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The Moon as it first becomes visible in evening skies, signalling the beginnings of months in many calendars, has been known as the “New” Moon, but since astronomers reserve that term for the earlier instant when it passes the Sun, I call this stage the Young Moon. On Jan. 2, sharp-eyed watchers in Europe may
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Libration is the apparent “rocking” of the Moon, caused mainly by its non-circular orbit around us and the 1.5° tilt of its own equator. This brings some of the Moon into our view beyond the mean limb (edge), so that over time we get to see not just 50% of the surface but 59%. The amount can vary from zero up to about 10.5°, which means that an extra 10.5/360 of the Moon’s circumference comes into view. <Zodiac charts> This month the libration is greatest (8.4°) on Jan. 6, and can be seen in the early evening toward the southern end of the still slender crescent, but it remains modestly large and convenient throughout the month.
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Extreme perigees, and tides: It happens also that at both ends of January the New Moon almost coincides with perigee, the Moon’s closest point, in its rather elliptical orbit, to Gaia, the Earth. <Moon distance graph> Perigee comes 10 hours after New Moon on Jan. 1, 12 hours before it on Jan. 30. When perigee is close to New or Full Moon, then Earth, Moon, and Sun are aligned, so the Sun’s tidal pull is added to the Moon’s greater pull. The result is that the Moon’s orbit is squeezed toward greater ellipticity, and the perigee is even nearer in. We cannot see this nearer and larger Moon, since it is lost in the Sun’s glare. But what we might observe at or just after dates like this is “spring” tides, tides of great amplitude. The nearness of the Moon on Jan. 1 and 30 is only exceeded on Aug. 10, when perigee coincides with a Full Moon; that we will be able to see.
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This year starts with a New Moon. The neat result is that January fits as well as it can to a lunation, or 29.5-day cycle of the Moon. And the next two months also have to coincide roughly with lunations, as months were originally intended to do. The Moon is New on Jan. 1 and again on Jan. 30; then there are no New Moon instants in short February; then again two in March. This pattern is found also in 1995 and 2033 (as expected from the 19-year near-repetition of Moon events, called the Metonic cycle).
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The Moon in January
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Jan. 14: the scene for latitude 40° north, one hour after sunset, looking toward the eastern horizon, above which the Moon and Jupiter have climbed. Jupiter is shown at this date, with a dot sized for its brightness, to compare with the stars. An arrow shows its travel in the course of the month (retrograde, or westward, around this time). It was at opposition on Jan. 5; the Moon will be Full early on Jan. 16. The scale is 4 mm to 1°, and the Moon is shown at true scale; the planet and stars really appear much smaller and dimmer than it. The Moon being so near and fast-moving, we show it (this time) in several positions: At the beginning and end of this Universal Time day (Jan. 14 0h and Jan. 15 0h), to give an idea of its motion. Also at one hour after sunset for longitudes 0° (Europe) and 75° west (eastern North America). The latter is 5 hours later, so the time is almost into the next UT day. And for those times we show it (1) as measured from the center of the Earth, and (2) displaced by parallax as seen from the locations (southward from a northerly place, eastward from Earth’s evening side). We use blue coloring to distinguish the Moons that can’t actually be seen (the geocentric ones). In ensuing pictures we’ll omit most of this elaboration, but by referring back to this one you can estimate where the Moon will be at times other than 0h UT, and as seen from actual places on Earth’s surface.
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Jan. 23: larger-scale view (1 cm to 1°) of the Moon passing between Mars and Spica. The time, for latitude 40° north, is an hour before sunrise; the southwestern horizon is about 16° below.
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Astronomical Calendar 2014
41
time
Sun Sun flight of the Earth
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2014 Oct 8 9:15 UT
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The year’s second eclipse season comes less than half a year (by about 6 days) after the first, because of the continual westward precession of the line of nodes. The Moon hits Earth’s outer shadow 9½ hours before reaching the ecliptic (an hour longer than at the April 15 eclipse) so it goes slightly less deeply in, and totality will last 61 minutes (18 shorter than in April). This time the Moon is descending toward the ecliptic, so it passes through the northern half of the shadow. Again it is the Pacific that happens to be facing the night and the Moon; indeed, more centrally than in April. All stages are seen at the north pole and in Alaska, the Canadian and US west, Hawaii, New Zealand, part of Australia and New Guinea, northeastern Siberia. More eastward in America, the eclipse is later in the morning hours; the Moon sets (and the Sun rises) during the closing stages. A zone from the Great Lakes to the Gulf does not see the end of the partial phase, and the east coast does not see the end of totality. Totality starts at 10:24 UT, which is 3:24 by Pacific clock time, 6:24 by Eastern. Uranus was at opposition only half a day ago, so during totality it appears a little to the south and west—and is occulted by the Moon, as seen from Arctic regions. Since its magnitude is 5.8, it should be just visible to the naked eye if conditions in the darkened sky are good. Interesting to reflect that in the centuries before its 1781 discovery Uranus could have been seen, and taken for a background star, not only during dark nights but on occasions like this when it was revealed by a darkening of the Moon.
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The October eclipse season ζ III—Total eclipse of the Moon, Oct. 8
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When the Moon comes around to New, it is longer after the middle of the eclipse season than it was on April 29 (by 17 hours); there is a longer time since it crossed the ecliptic (by 23 minutes), so the axis of the shadow misses Earth by a wider margin, and t greatesse the eclipse is purely partial. The Moon eclip has crossed the ecliptic northward, so l e the shadow now brushes our northern c i r C hemisphere. The Moon is at a greater i c distance than it was on April 29, so the c t r N A 60˚ umbra ends farther (by 2.2 Earth-radii) short of reaching Earth’s distance, and CETUS first contact z the core of the shadow that sweeps of penumbra---------------------past us is the antumbra; even if it pointed at us, the eclipse seen from within it CETUS would be not total but annular. PISCES The advancing penumbra meets Earth at sunrise in the Bering Sea, AQUARIUS (or whatever) south of Russia’s Kamchatka peninsu20:00 la, at 19:38 UT. By 20 UT, which is 12 21 noon by Alaska summer clock time, the n :0 Ca 0 penumbra has spread over the f o Aleutians and most of Alaska. Western 30˚N i c o p Canada, the western US, and most of T r 22:00 Mexico see the silhouette of the Moon moving across the Sun: more deeply for places to the northeast, but also later in the afternoon. The deepest eclipse, with 81% of the Sun’s width covered (the magnitude of the eclipse), is at the point over which the shadow’s axis passes nearest overhead: at the southern tip of Prince of ion rotat our Wales Island in the Canadian Arctic. h 1 in For central Canada and the central US the eclipse is in progress at sunset. New York, New England, and eastern Canada have turned away into night before the eclipse reaches them. The penumbra’s last contact is at a point in i c op T r Texas.
flight of the umbra in 1 hour (relative to Eartj cemter)
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ECLIPSE SEQUENCES. Pictures for each place are at 30-minute intervals, centered on mid eclipse. This time is given in UT, followed by translation into the place’s standard 24-hour clock time (ignoring “summer” time). Then is given the altitude of the Sun at mid eclipse. Scale for Sun and Moon is 1 cm to 1 degree, but distances between the Sun’s positions are compressed. Angular directions are correct for the horizon at the place, and suggest the Sun’s movement across the sky. For places east of noontime eclipse, Sun and Moon slope down the sky in the afternoon. When Sun or Moon is below the horizon it is shad-
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Astronomical Calendar 2014
k
Deneb
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ZODIAC CHARTS
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PISCES 6
e q u a t o r Deneb
equa t or
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VIRGO
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January
the way east (left) toward the next date’s position; for the Central, Mountain, and Pacific zones, 6/24, 7/24, and 8/24 of the way. Its position is as seen from the center of the Earth, i.e. not adjusted for parallax; from a northern latitude it will be displaced slightly south. Its size is exaggerated 8 times; it appears slightly larger near perigee (such as Jan. 1) than apogee (such as Jan. 16). Gray areas are the dark maria (“seas”). We sometimes show stars and Arcturus planets in front of the Moon, which, being exaggerated in size, would otherwise hide them much more often than it really does.
These charts are of the zodiacal band of the sky, within which the Sun, planets and MoonVega are seen from Earth. (The band shown is 40° wide, centered on the ecliptic.) Arrows show the planets’ courses during each month. The Sun is shown at the 15th of the month; its disk is exagggerated 8 times in apparent size. Its great glare is indicated schematically; the Sun’s positions at the beginning and end of the month are about at the right and left edges of this glare. The Moon is shown for each date at 0h Universal Time (Greenwich midnight). For local midnight at longitude 75° M west (in America’s AltairEastern time zone) it will be 5/24 of W i a
ec
5
lip tic
Feb 1
ptu ne
OPHIUCHUS
Vega
New 31
4
Ne
3
30 Venus 2
AQUARIUS
New Jan 1
29
27
28
r uarte Last Q24
LIBRA 26
rs Ma
rn Satu
25
Jan
22
23
Spica
SAGITTARIUS
Me
r
cu CAPRICORNUS r y
Pluto
ecl ipt ic
Jan 15
Arcturus
Antares
M
y
VIRGO
equa tor
Feb 18
y
AQUARIUS
y
Ne ptu ne
SCORPIUS
equa t or
Deneb k
February
l
Ne Mar w 1
2
Altair
y
3 PISCES
l k Mi ay W
SAGITTARIUS
M W i a
lk i y a W
Fomalhaut
AQUARIUS Feb 1 28
OPHIUCHUS
Vega 27
Me rcu Feb 15 ry
Venus 25 26
Last Quarter 23
24
19
rs
Ma
Saturn
Spica
20 21
22
Pluto ecl ipt ic
CAPRICORNUS
Arcturus
Antares LIBRA
M lk i y a W
y
y VIRGO
equa tor
y
Mar 15
SCORPIUS
y
March
equa t or
k
New Mar 1
29
SAGITTARIUS
Altair
l
30 PISCES 2
M W i a e q u a t o r Deneb
l k Mi ay W
Fomalhaut
28
Ne ptu
ne Mer
26
AQUARIUS
Venus
rs Ma
n tur
19
Sa
Pluto ec l ip tic
CAPRICORNUS
LIBRA
Last Quarter 24
25
cur y
OPHIUCHUS
Vega
27
18 Mar
20
21
22
23
Spica
Arcturus
Antares M equa t or
y
Altair
l
PISCES 26
SAGITTARIUS
lk i y a W
M W i a e q u a t o r Deneb
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Apr 15
l k Mi ay W
Fomalhaut
SCORPIUS
k
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AQUARIUS 24
M
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VIRGO
equa tor
y
April
25
OPHIUCHUS
Vega
V y Ne enus ptu ne
23
Last Qu art 22 er
21
AQUARIUS
20
LIBRA
18
19
Pl
urn Sat
4
1 Apr
Spica 15ull F
16 17
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CAPRICORNUS
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Arcturus
Antares M lk i y a W
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VIRGO
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May
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May
Qu 22 arter
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SAGITTARIUS
Altair
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PISCES 23
M W i a e q u a t o r Deneb
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Fomalhaut
OPHIUCHUS
Vega
21
Ne ptu ne
20
19
18
AQUARIUS
Full 15
16
17
12 Mars
LIBRA
13
rn
14
Pluto ec l ip tic
CAPRICORNUS
Spica
Satu
Arcturus
Antares M
SAGITTARIUS
lk i y a W
y
equa t or
Altair
PISCES 19
equa t or
June
y
l k Mi ay W
Fomalhaut
18
OPHIUCHUS
17
N
ep tu
SCORPIUS
15
14
Full
AQUARIUS CAPRICORNUS
ec l ip tic
13
12
11
Pluto
Antares M
SAGITTARIUS
lk i y a W
Fomalhaut
rn Satu
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VIRGO
s ar
LIBRA
16
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equa tor
M
Spica 9 10
8 Ju n
11
Astronomical Calendar 2014 Algol
M i W lk a y
y GEMINI
Castor Pollux
CANCER
M35
Jupiter
Beehive
Pleiades 13
ARIES
12
11
Hyades
LEO
Regulus t ic l ip
18
20 21
CANCER
Pleiades 9 10
13
Aldebaran
5
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17
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Castor Pollux
iter Jup Sirius
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Regulus
13
15
CANCER
LEO
Castor Pollux
GEMINI Canopus
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Beehive
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Apr 1 2 8
an SO nular ECLIL AR Apr PSE 29
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Betelgeuse
New 29
CETUS
Achernar Pleiades
ARIES
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PISCES
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M Wa
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Ur an Ve us nu s
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Pleiades
Achernar ARIES
24
26
Aldebaran Hyades
Ven u
s
equa t or
22
21
Ur
TAURUS
Betelgeuse
PISCES
23
ORION
Procyon
May 24
CETUS
25
27 New
28
25
Rigel
cu Jun 15
30 1 Jul
TAURUS
26 27
Algol
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29
5
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Canopus M
3
4
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GEMINI
Apr
27 U Apr 15M ranu s er cu ry
Rigel
ORION
Procyon
Beehive
i
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Mercury
ter
CANCER
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TAURUS
1 28 May 15 Aldebaran M
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5
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LEO
Canopus
1 Jun
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10
30
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6
8
9
3
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Mi Wa l k y y
Regulus
CETUS
ARIES
May 1
equa t or
M35 Jupiter Sirius 4 31
Beehive
4
ORION
GEMINI
Castor Pollux
CANCER
LEO
5
M i W lk a y
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an
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Sirius Libration is shown in these charts by red tabs on the Moon. Each is at the place on the Moon’s limb (edge) most librated toward us, and its outward width is proportional to the amount of the libration. At and near this place you can see with your telesope a few degrees past the average horizon into the foreshortened features of the Luna Incognita (“unknown Moon”) on our y k l y i M Wa
Jun 20
us QuLaast rter
CETUS
Canopus
us
Rigel
Betelgeuse
Procyon
Mar 3
an
Aldebaran
Mi Wa l k y y
l
Ur
Hyades
12
New 31
TAURUS
Mar 15
6
7 First Quarter
e q u ay t o r
5
Pleiades
9
11 13
Hyades
M35
M i W lk a y
Regulus
PISCES Apr 1 4
6
Algol
8
ic ipt e c l 10
ARIES
7
y M i W lk a y
i M Wa
y
Feb 15
Achernar
equa t or
Mi Wa l k y y
k
Pleiades 8
Betelgeuse
Procyon
equa t or y
l
ecl ipt ic
Aldebaran
16
Full 17
CETUS
Rigel
ORION
CANCER
us
Algol
First Quarter 9
10
11
12
M35
Ur an
equa tor
y
GEMINI Canopus
Beehive LEO
equa t or
Mi Wa l k y y
l
Feb 4
TAURUS
Betelgeuse
Procyon
e q u a t o yr
PISCES 6
ORION
M i W lk a y
15
ARIES First Qu arter 7
8
14
16
Jan
CETUS
M35
11
us 7
Rigel
Hyades
12
an
Algol
p t i c ec l i
Full
Ur
equa tor
y
iter JupSirius
LEO
Regulus
TAURUS
equa t or
GEMINI
Castor Pollux
Beehive
First Qua rter 8
9
Betelgeuse
Procyon
equa t or
Aldebaran
M i W lk a y
19
PISCES
10
ORION
Mi Wa l k y y
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17
14
15
16 Full
61
Rigel Achernar neighbor small planet’s far side. But if the place is on the dark half of the limb, where you can’t see anything, the libration is of no advantage; this is indicated with a tab of paler color. The librationspot is always on the hemisphere nearer to the ecliptic, because when the Moon is south of the ecliptic plane we are looking slightly “down” on it—its north pole is in view—and vice versa.
Astronomical Calendar 2014 289P (formerly designated D/1819 W1) Blanpain. We mention it not because it is likely to be observable but because we are at a node in its history. It was discovered by Jean-Jacques Blanpain (his name if he’d been English might have been Whitbread) on 1819 Nov. 28, and indeEarth pendently a week later by the prolific comet-disMars coverer Jean Louis Pons. ItJupiter was observed over 59 days, but then, despite Jupiter being in one of the Ciffréo shortest of orbits (just over108P 5 years), seemed never to return. It had presumably broken up, and in the modern system of nomenclature it was one of the handful with the prefix “D,” meaning that though periodic it was Disappeared, or Dead. On 1956 Dec. 5, south-hemisphere observers saw a burst of bright meteors, which have continued at much lesser rates as the Phoenicid shower of early December (see the METEORS section). H.B. Ridley, who first studied these meteors, realized that they are roughly in the orbit of the lost comet. Then one of the multitude of asteroids discovered in 2003, called 2003 WY25, was found to be in the same orbit; though only 0.025 away it was no brighter than magnitude 14. In 2004, probably in outburst, it showed a small coma; on 2013 July 4,
8P
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Feb
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1 Apr
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Bl anpai n
Ma r s Apr Aug
Oct
Sep
OctAug 11 12 Jul
Apr
C / 20 13
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S i di ng
S pr i ng
As the comet comes in and we overtake it at opposition on May 19, it is still 1.75 AU out from us, perhaps at mag. 18, making its apparent retrograde loop in southern Libra. Twice it is near to Antares, nearly reaching it on Mar. 27, passing close south of it on Oct. 10. We leave it behind, so that when it comes up to perihelion on Dec. 26, just inside the late-September part of our orbit and just south of the ecliptic (which it will cross on Jan. 5), we look back on it more than 1.4 AU away in Capricornus, at perhaps its brightest magnitude of 13 but only 43° from the evening Sun.
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May
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11
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-16˚ -16
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Aug
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1 11 May
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21
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Sep
Jun 1
Sep 1 1 Jan 11 1 Jun 9P 2 1 SW
10m -24˚
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Apr
Dec
1
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May 1
21
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Feb
-20˚ -20
-26˚
27 15
CAPRICORNUS
11
28
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Graffias
-14˚ -14
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Aug Dec
Oct 16
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AQUARIUS
Dec
Oct
ecliptic C/2013 A1 Siding Mars b Spring is one of the horde of discoveries made by Robert McNaught at the Siding Spring Observatory El Nath in New South Wales (“A1” because the date was 2013 Jan. 3). It has Oct -24˚ -24 -24˚ -24 dropped from the Oort Cloud in a retrograde orbit; the inclination of 129° means that it cuts o 13 14 15 17 19 21 northward through the ecliptic at 51° counter to Earth’s direction. On April 19 the comet 36°25 24 23 27is26 south of the Sun, in Fornax; then it appears to dive even farther south; on Aug. 25 is at opposiq tion in Tucana, still 0.96 AU from us; it appears southernmost on Sep. 2 at declination —75°, -26˚ -26 just inside Octans, the constellation that contains the south celestial pole. In space it is all the -26 -26˚ time rising toward the ecliptic plane, and as we reach the September part of our orbit we see it for a while comparatively close (0.89 AU on Sep. 4); around now, progressing into Pavo, its brightness may top out at magnitude 8. It climbs through Scorpius into Ophiuchus, and intersects Mars’s orbit—at the point C/2013 -28 -28˚ -28˚ -28 A1 where Mars now is! On Oct. 19, comet misses planet by only about 0.001 AU, though the uncerSiding tainty is enough that the nucleus, perhaps 4 km wide, could hit Mars, at 56 km/sec. Even if it Spring doesn’t, its orbit will be altered. Planet and comet are outward from where Earth was in July, so we look back on them in the evening sky, 59° east of the Sun, 1.62 AU away.g 1After ascendx -30˚ -30˚ -30 30m 40m 17h2-30 0m 50m ing node (Oct. 22) and perihelion (Oct. 23) and appearing 2° south of the Moon on the night of g 2 Oct. 27/28, the comet continues to climb and fade. Mars is drawn at 200 times its size.
m
Jupit er
-22˚ -22
-22˚ -22
15P Finlay was discovered on 1986 Sep. 26 by William Henry Finlay at the Cape observatory in South Africa. With its period varying from 62⁄3 to nearly 7 years, it has been seen at 14 visits before this one. It’s a good example of how a typical short-period comet with aphelion near Jupiter’s orbit is controlled by the great planet: when it arrived out there in May 2008, it found itself only 0.28 AU l a gravitational tug: its orbit slewed westward (ascending n from Jupiter and felt node retreating from 42° to 14° from the vernal equinox), its inclination increased from 4° to 7°, and its perihelion pulled from just outside to just inside Earth’s orbit. 30m 20m 40m 10m 50m 21h 22h
a short tail also. It is now recognized as the lost comet. This year it returns to its perihelion, just inside and north of the December part of our orbit; unfortunately it does so in August. The result is that in the early part of the year it is far away beyond the Sun; in August, as we come around into view of it, it is more than 1.5 AU ahead, out in our morning sky, in Gemini, peak magnitude possibly 13, probably dimmer. At its next return, in January 2020, it will pass 0.09 AU from Earth.
17h20m -20˚ -20
OPHIUCHUS x
Nov 11
20m
30m
40m
50m -20 -20˚
26
NOV 17 2 1
+32˚
SAGITTA ARIUS
i
108P Ciffréo was found by Jacqueline Ciffréo on 1985 Nov. Dec 8 on photographs at the observatory of Caussols in Provence. It has a period of about 7.2 years, Dec Oct so the present return will be its Oct third since discovery. In the early part of the year it is behind the Sun (appearing 9° south of it on Feb. 4). It climbs in the morning sky through the head of the 1 Cetus and close past whale Aldebaran. It is aiming for a perihelion point that is just before m Feb ascending node and 0.7 AU out21 side the early-November part of 5h 10m our orbit; it arrives there on Oct. 6 18, rather earlier than we would 1 1 like but quite favorable. We see ˚ +36 1 it still somewhat ahead in the morning sky, ½° south of Aldebaran on Sep. 18 and then between the two horn-tip stars of ˚ +34 Taurus, 0.935 AU away and perhaps at magnitude 11. In i November, though it is now on its 108P way out, we overtake it, so Ciffréo +32˚ it is nearest (just under 0.8 Ciffr AU) on Nov. 27, and at opposition on Dec. 12, climbing in Auriga. +30˚ 5h 10m
Jupit er
65
-28˚
1l 21 Ju -30˚ 29P
Schwass m a n n - Wa c hm a n n
1
-32˚
29P Schwassmann-Wachmann 1 was discovered by Arnold Schwassmann and Arno Arthur Wachmann at the Hamburg observatory in 1902. They discovered two more periodic comets, in c 1929 and 1930, and were x 12 co-discoverers of a non-periodic one with Leslie Peltier in 1930. But 29P is one of a kind: in an almost circular orbit aty1a huge distance, beyond Jupiter, where a smaller comet y2 would be even fainter than its usual magnitude of about 17. Even so, it would hardly be observable
but for its occasional drastic brightenings, which are worth watching for every year. It was last at perihelion in 2004, so in its 15-year orbit it is now drawing slightly closer, toward its next perihelion in April 2019, in the Pisces direction. This year, 15P Finlay happens to pass 29P just when Earth passes them both, so that they trace parallel loops and are almost simultaneously at opposition, on May 19 (15P) and 20 (29P), the greater comet 3° to the south and nearly 3 times farther away.
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Astronomical Calendar 2014 2014 Jan. 25 14h Saturn mag. 0.6 elong. 73˚ 73 W
2014 Feb. 21 22h Saturn mag. 0.5 elong. 99˚ 99 W
2014 Feb. 26 5h Venus mag. -4.6 elong. 43˚ 43 W
2014 Mar. 21 3h Saturn mag. 0.4 elong. 127 127˚ W
2014 Apr. 17 7h Saturn mag. 0.2 elong. 155˚ 155 W
2014 May 14 12h Saturn mag. 0.1 elong. 175˚ 175 E
2014 June 10 19h Saturn mag. 0.3 elong. 147˚ 147 E
2014 June 26 12h Mercury mag. 3.5 elong. 10 10˚ W
2014 July 6 1h Mars mag. 0.1 elong. 96˚ 96 E
2014 July 8 2h Saturn mag. 0.5 elong. 120˚ 120 E
2014 Aug. 4 11h Saturn mag. 0.6 elong. 94˚ 94 E
2014 Aug. 14 17h Uranus mag. 5.8 elong. 125 125˚ W
2014 Aug. 31 19h Saturn mag. 0.7 elong. 69˚ 69 E
2014 Sep. 11 2h Uranus mag. 5.7 elong. 152˚ 152 W
2014 Sep. 28 0h 1 Ceres mag. 9.0 elong. 43˚ 43 E
2014 Sep. 28 4h Saturn mag. 0.7 elong. 45 45˚ E
2014 Sep. 28 15h 4 Vesta mag. 7.8 elong. 50˚ 50 E
2014 Oct. 8 11h Uranus mag. 5.7 elong. 179˚ 179 E
2014 Oct. 22 22h Mercury mag. 1.7 elong. 11˚ 11 W
2014 Oct. 23 21h Venus mag. -3.9 elong. 1˚ 1 E
2014 Oct. 25 16h Saturn mag. 0.6 elong. 21˚ 21 E
2014 Nov. 4 18h Uranus mag. 5.7 elong. 151˚ 151 E
2014 Dec. 2 0h Uranus mag. 5.8 elong. 123˚ 123 E
2014 Dec. 29 5h Uranus mag. 5.8 elong. 95˚ 95 E
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