My first Magazine Sky & Telescope - 03.2019 | Page 46

MARCH 2019 OBSERVING
Planetary Almanac
PLANET VISIBILITY Mercury: visible at dusk through the 6th • Venus: visible at dawn all
month • Mars: visible at dusk, sets late evening • Jupiter: rises early morning, visible th rough dawn
all month • Saturn: visible at dawn all month
Mercury
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March Sun & Planets
31
21
Date Right Ascension Declination Elongation Magnitude Diameter Illumination Distance
1 22 h 45.6 m –7° 53′ — –26.8 32′ 17″ — 0.991
31 0 h 35.8 m +3° 51′ — –26.8 32′ 02″ — 0.999
1 23 h 48.2 m +0° 52′ 18° Ev –0.2 7.7″ 39% 0.876
11 23 h 44.8 m +2° 17′ 8° Ev +3.6 10.2″ 4% 0.658
21 23 h 14.4 m –2° 13′ 11° Mo +3.2 10.9″ 6% 0.615
31 23 h 08.9 m –5° 29′ 24° Mo +0.9 9.5″ 27% 0.705
1 20 h 03.5 m –19° 33′ 41° Mo –4.1 15.6″ 72% 1.070
11 20 h 52.7 m –17° 20′ 39° Mo –4.0 14.7″ 75% 1.138
21 21 h 40.9 m –14° 17′ 37° Mo –4.0 13.9″ 78% 1.204
31 22 h 27.8 m –10° 34′ 35° Mo –3.9 13.2″ 81% 1.268
1 2 h 27.7 m +15° 17′ 60° Ev +1.2 5.3″ 91% 1.767
16 3 h 07.7 m +18° 24′ 55° Ev +1.3 4.9″ 93% 1.892
31 3 h 48.6 m +20° 57′ 50° Ev +1.4 4.7″ 94% 2.012
1 17 h 23.6 m –22° 33′ 78° Mo –2.0 36.2″ 99% 5.445
31 17 h 33.6 m –22° 40′ 106° Mo –2.2 39.7″ 99% 4.963
1 19 h 15.5 m –21° 52′ 52° Mo +0.6 15.6″ 100% 10.632
31 19 h 24.3 m –21° 37′ 80° Mo +0.6 16.3″ 100% 10.178
Uranus 16 1 h 53.1 m +11° 04′ 35° Ev +5.9 3.4″ 100% 20.656
Neptune 16 23 h 10.9 m –6° 19′ 9° Mo +8.0 2.2″ 100% 30.920
Venus
Sun
Mercury
31
16
1
Mars
1
16
31
Venus
Jupiter
Mars
16
Jupiter
Saturn
Saturn
16
Uranus
Neptune
The table above gives each object’s right ascension and declination (equinox 2000.0) at 0 h Universal Time on selected dates,
and its elongation from the Sun in the morning (Mo) or evening (Ev) sky. Next are the visual magnitude and equatorial diameter.
(Saturn’s ring extent is 2.27 times its equatorial diameter.) Last are the percentage of a planet’s disk illuminated by the Sun and
the distance from Earth in astronomical units. (Based on the mean Earth–Sun distance, 1 a.u. is 149,597,871 kilometers, or
92,955,807 international miles.) For other dates, see skyandtelescope.com/almanac.
10"
PLANET DISKS have south up, to match the
view in many telescopes. Blue ticks indicate the
pole currently tilted toward Earth.
+40°
22 h
20 h
18 h
16 h
14 h
12 h
RIGHT ASCENSION
Vega
+30°
Mar
20-21
AQUILA
OPHIUCHUS
Mercury
VIRGO
0°
Neptune
6 h
4 h
Regulus
EC
LIP
TIC
Pleiades
–20°
31
CAPRICORNUS
Fomalhaut
–30°
25
CANCER
Betelgeuse
Procyon
ORION
Jupiter
Spica
CORVUS
8 am
6 am
4 am
Mar 10
+20°
Uranus
TAURUS
EQUATOR
Sirius
ERIDANUS
HYDRA
CANIS
MAJOR
Antares
SCORPIUS
+30°
ARIES
Rigel
Saturn
SAGITTARIUS
10 am
28
+40°
Mars
13
LIBRA
1
2 h
GEMINI
16
AQUARIUS
Venus
–40°
Castor
Pollux
LEO
Arcturus
HERCULES
+10°
8 h
BOÖTES
CYGNUS
+20° PEGASUS
10 h
Mar 1
LOCAL TIME OF TRANSIT
2 am
Midnight
10 pm
8 pm
6 pm
4 pm
2 pm
The Sun and planets are positioned for mid-March; the colored arrows show the motion of each during the month. The Moon is plotted for evening dates in the Americas when it’s waxing (right side
illuminated) or full, and for morning dates when it’s waning (left side). “Local time of transit” tells when (in Local Mean Time) objects cross the meridian — that is, when they appear due south and at
their highest — at mid-month. Transits occur an hour later on the 1st, and an hour earlier at month’s end.
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M A RCH 2 019 • SK Y & TELESCOPE
–10°
–20°
–30°
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