SCORPIUSVIRGOCENTAURUSOPHIUCHUS LIBRASpicaJupiterJanuary 11, 6 A.M.
Looking southeastMarsMoon10°Antares1°TAURUS121109 108
114cM1 Jan 1(^6111621)
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Path of Massalia
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Massalia horns in on Taurus the Bull
The Moon slides past Mars and Jupiter (^)
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Asteroid 20 Massalia reached
opposition in mid-December,
which places it high in January’s
evening sky and not far from its
peak brightness. Massalia glows
at 9th magnitude this month as
it treks across eastern Taurus.
Although you might think
the asteroid would be difficult
to locate among the swarms of
faint Milky Way stars, it fortu-
itously passes in front of the
dark clouds of dust and gas
in this region. Only a relative
handful of stars shines through,
leaving the 90-mile-wide aster-
oid in the open.
Avoid looking for it on the
first few and last few nights
of the month when the Full
Moon lies nearby. Start at 3rd-
magnitude Zeta (ζ) Tauri, the
star that marks the tip of the
Bull’s southern horn.
Take a quick look at the Crab
Nebula (M1) 1° to the northwest
before targeting 5th-magnitude
114 Tau 1.6° farther west. Just
three stars matching Massalia’s
brightness reside near the path
to 5th-magnitude 109 Tau,
which lies 2° west of 114. Your
best bet for seeing Massalia
move during a single observing
session comes the evenings of
January 10 and 11, when the
asteroid slides 0.2° south of
109 Tau.
LOCATINGASTEROIDS
Out of darkness comes the light
Scorpion’s brightest star, mag-
nitude 1.1 Antares. The star’s
name literally means “rival of
Mars,” and the similarities
between their brightnesses
and hues this month will
help you understand why
ancient astronomers made
the comparison.
This new season of Jupiter
observations promises some
splendid views through a tele-
scope. The best observing
comes shortly before twilight
starts to paint the sky. In mid-
January, the giant planet
stands some 30° high in the
southeast at that time, and its
34"-diameter disk should look
impressive through any tele-
scope. Notice the two dark
equatorial belts that sandwich
a brighter zone coinciding with
Jupiter’s equator.
The jovian satellites are also
worth a look. You’ll typically
see the four brightest — Io,
Europa, Ganymede, and
Callisto — arrayed beside the
planet’s disk, though occasion-
ally one or more will hide in
front of or behind Jupiter. A
good example of vanishing
moons comes January 10. At
5:28 a.m. EST, Io and Europa
simultaneously disappear into
the giant planet’s shadow.
Track the two moons for the
half-hour leading up to the
eclipse and then watch them
fade over several minutes.
You can find Mercury to
the lower left of Mars and
Jupiter during January’s first
three weeks. The innermost
planet reaches greatest elonga-
tion on the 1st, when it lies 23°
west of the Sun and stands 11°
high in the southeast 30 min-
utes before sunrise. It shines at
magnitude –0.3, more than a
full magnitude brighter than
ruddy Antares 11° to its right.
A view through a telescope
reveals the planet’s disk,
which spans 6.7" and appears
62 percent lit.
Mercury loses altitude
each morning. On January 10,
it’s still a decent 8° high a half-
hour before sunup, but that
drops to just 4° by the 20th.
Although the planet remains
at magnitude –0.3 throughout
this period, it becomes pro-
gressively harder to see in
bright twilight. Its disk also
shrinks and becomes more
fully illuminated, making tele-
scopic views less appealing.
But you’ll want to be
sure to look for Mercury on
January 13 because Saturn
then lies just 0.6° north of the
inner world. You’ll probably
need binoculars to spot the
magnitude 0.5 ringed world
in the bright twilight.
But unlike its neighbor,
Saturn climbs higher with
each passing day. By the end of
the month, the planet appears
10° high in the southeast an
hour before sunrise. You
should be able to spot it easily
among the background stars of
Sagittarius. Unfortunately,
Saturn’s low altitude means it
won’t look that great through
a telescope. You’re better off
waiting a month or two for it
to return to glory.
The last of the solar sys-
tem’s major planets remains
out of sight all month. Venus
reaches superior conjunction
January 8/9, when it passes on
the opposite side of the Sun
from Earth. Look for it to
reappear low in the evening
sky in late winter.
A waning crescent Moon stands above Mars and Jupiter in the predawn
sky January 11. Brilliant Jupiter shines 20 times brighter than ruddy Mars.
This 9th-magnitude asteroid should be easy to find during January
as it moves slowly against the backdrop of eastern Taurus.
Martin Ratcliffe provides plane-
tarium development for Sky-Skan,
Inc., from his home in Wichita,
Kansas. Meteorologist Alister
Ling works for Environment
Canada in Edmonton, Alberta.