skyandtelescope.com • JUNE 2019 47tquThese scenes are drawn for near the
middle of North America (latitude 40° north,
longitude 90° west); European observers
should move each Moon symbol a quarter of
the way toward the one for the previous date.
In the Far East, move the Moon halfway. The
blue 10° scale bar is about the width of your fi st
at arm’s length. For clarity, the Moon is shown
three times its actual apparent size.
planet. At its highest in the middle of
the night, Jupiter is barely high enough
for its image to likely be steady and
sharp. Even so, there is so much to look
for in Jupiter’s cloud features — and
the events of its large Galilean satel-
lites. (For the timings of Great Red Spot
central passages and Galilean moon
phenomena, see pages 50–51.)
Jupiter spends June retrograding just
above the body of low Scorpius. At least
this is a rich and beautiful section of
the heavens. Also, we can enjoy watch-
ing Jupiter’s separation from Antares
shrink from about 12° to less than
9° during June. Meanwhile, Jupiter’s
retrograde is much faster than Saturn’s,
so the former increases its separation
from Saturn by 2° in June, carry-
ing Jupiter out to almost 31° from its
splendor-ringed rival.
Saturn rises about 2½ hours after
sunset as June opens but very early in
evening twilight as the month closes.
The deep-gold-colored world brightens
from magnitude +0.3 to +0.1 (rivaling
Vega) during June. Saturn shines left
or upper left of the large Teapot aster-
ism of Sagittarius and just below the
little Teaspoon asterism. Saturn is at
its highest several hours after midnight
(daylight-saving time), so that’s the best
time to observe its globe and rings in
the telescope. The globe of Saturn grows
to an apparent equatorial diameter of
more than 18′′ during June. Saturn will
arrive at opposition on July 9th.START OF DAWN
Neptune and Uranus are best seen in
the sleepy hours during this month’s
long morning twilights (if you live
around latitude 40° north or far
enough south to even have full night at
any time in June). Neither is yet well-
placed for observation, but if you want
to take a crack at them check out fi nder
charts at https://is.gd/urnep.DAWN
Venus rises less than an hour before
the Sun this month. On June 18th
Aldebaran will be about 5° lower right
of the magnitude –3.8 planet. Even with
binoculars this is a hard catch, but it’s
well worth a try.SUN AND MOON
The Sun arrives at the June solstice at
11:54 a.m. EDT June 21st, making this
the longest day of the year in North
America. The June solstice marks the
start of summer in the Northern Hemi-
sphere and the start of winter in the
Southern Hemisphere.
The Moon is a slender waxing
crescent some 6° upper left of Mars at
nightfall on June 5th and at the end of
a long arc with Castor and Pollux the
next night. A thicker lunar crescent
hangs less than 4° above Regulus on the
evening of June 8th. A heavily gibbous
Moon forms a fairly large, nearly equi-
lateral triangle with Jupiter and Antares
on the evening of June 15th. The next
night, the Moon is closer to Jupiter, to
the brilliant planet’s lower left or left.
Late on the evening of June 18th, the
night after full Moon, the round lunar
orb is less than 2° below Saturn. On the
last day of the month, the waning lunar
crescent is in the Hyades.¢FRED SCHAAFteaches astronomy at
Rowan University and Rowan College at
Gloucester County.Jupiter
SaturnUranusNeptuneMercuryVenusEarthMarsMarch
equinoxJune
solsticeDecember
solsticeSept.
equinox
SunORBITS OF THE PLANETS
The curved arrows show each planet’s movement during June. The outer planets don’t change
position enough in a month to notice at this scale.skyandtelescope.com • JUNE 2019 47Dusk, June 28
30 minutes after sunsetCastor
PolluxMercury
MarsLooking West-NorthwestDawn, June 30 – July 1
30 minutes before sunriseAldebaranTAURUSVenusMoon
June 30Moon
July 1Looking East-NortheastPleiades