10°AURIGAPERSEUSCapella TAURUSMercury
AldebaranJune 24, 30 minutes before sunrise
Looking east-northeast1°HERCULESbh8470737983Path of PallasJune 1(^6111621)
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July 1
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A visit to the Strongman
Spy the innermost planet before dawn (^)
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18" across its equator while the
rings span 42" and tilt 24° to
our line of sight. The best views
come within an hour or so of
when Saturn climbs highest in
the south, at roughly midnight
local daylight time June 1 and
two hours earlier by the 30th.
After savoring the photons
ref lecting off Saturn and its
rings, turn your attention to
the planet’s array of bright
moons. Giant Titan glows at
8th magnitude and shows up
through any telescope. It’s the
brightest point of light in
Saturn’s vicinity except on
June 23 and 24, when the
planet and its attendants slide
within 2' of a 7th-magnitude
background star.
Titan revolves around
Saturn once every 16 days.
Three 10th-magnitude moons
— Tethys, Dione, and Rhea
— circle the planet inside of
Titan’s orbit. They appear
clearly through 4-inch and
larger scopes. An 8-inch
instrument will bring in 12th-
magnitude Enceladus when
this inner moon lies farthest
from Saturn.
Outer Iapetus is the Dr.
Jekyll and Mr. Hyde of solar
system objects. One of its
hemispheres ref lects light like
newly fallen snow, while the
opposite side more closely
resembles coal. The moon’s
brightness varies from 10th
magnitude when it lies far-
thest west of Saturn and its
ref lective side faces us to 12th
magnitude when it stands far-
thest east. The easiest times to
spot it this month come on
the evenings of June 7–9 when
it passes north of Saturn and
glows at 11th magnitude.
Iapetus fades thereafter as it
heads toward greatest eastern
elongation June 28.
Neptune is a binocular
object before dawn, when it
lies in the southeastern sky
among the background stars
of Aquarius. It remains 2°
southwest of 4th-magnitude
Lambda (λ) Aquarii all
month. The planet glows at
magnitude 7.9, so it is a dim
object in 7x50 binoculars, and
the handful of similarly bright
stars in its neighborhood
makes identification difficult.
To confirm a sighting, point
your telescope at the sus-
pected planet. Only Neptune
will show a blue-gray disk
measuring 2.3" across.
Like its outer neighbor,
Uranus shows up best shortly
before dawn starts to paint the
sky. The magnitude 5.9 planet
lies against the faint stellar
backdrop of Pisces. Use mag-
nitude 5.2 Zeta (ζ) Piscium as
Asteroid 2 Pallas stands out
from the family of asteroids
like a black sheep. Unlike most
main-belt objects, Pallas’ orbit
inclines steeply to the plane of
the solar system. (Of the first
1,000 asteroids discovered,
Pallas’ 35° inclination is the
highest.) A big impact likely
kicked it into this odd orbit.
Pallas reaches opposition
and peak visibility June 11,
though it’s easy to find through
binoculars or a telescope all
month. It glows at 9th magni-
tude among the background
stars of Hercules, a region
already halfway to the zenith
in the eastern sky as night set-
tles in. Use the StarDome map
at the center of the magazine
to zero in on magnitude 3.1
Delta (δ) Herculis, your jumping-
off point for finding Pallas.
You can hop quickly to Pallas
June 12–14 when it passes 33'
(just over one Full Moon diame-
ter) south of magnitude 4.4
Lambda (λ) Her. The asteroid
will be even easier to find June
30 when it pulls within 26' of
Delta Her. You can detect Pallas’
motion in a four-hour observing
session June 3, 5, 7, and 11 when
background stars provide a con-
venient framework.
LOCATINGASTEROIDS
Play it again, Pallas
a guide. Uranus lies within
1° of this star all month and
passes 0.5° due south of it June
- A telescope reveals Uranus’
3.5"-diameter disk and blue-
green color.
Our final solar system tar-
get appears low in the east-
northeast before dawn in late
June. Mercury reaches greatest
elongation on the 24th, when it
lies 22° west of the Sun and
stands 7° high a half-hour
before sunrise. Shining at mag-
nitude 0.4, it shows up easily
through binoculars if you
have an unobstructed hori-
zon. Don’t confuse it with
ruddy Aldebaran, the 1st-
magnitude luminary of
Taurus, which lies 2° south
(lower right) of the planet that
morning. A telescope will
show Mercury’s disk, which
appears 8" across and about
one-third lit.
Only Mars remains invis-
ible this month. It passes
behind the Sun from our
viewpoint June 14.Mercury hangs low on mornings around June 24, when it lies 22° west of
the Sun at its summertime peak for Northern Hemisphere observers.
Pallas reaches its peak at opposition June 11, though the 9th-magnitude
asteroid will be easy to spot all month among the stars of Hercules.