Astronomy - USA (2020-06)

(Antfer) #1
Path of Pallas

30

June 1

5

10

15

20
25

1 °

N

E

9

1
1

(^54)
7
SAGITTA U
VULPECULA
WWW.ASTRONOMY.COM 43
LOCATING ASTEROIDS I
Crossing the Great Rift
YOU WON’T HAVE TO BE SLY to track 2 Pallas across the terri-
tory of Vulpecula, the celestial fox. With a 4- or 6-inch scope from
the suburbs, you can nab this main-belt asteroid by dropping
south of the lovely double star Albireo, or by scooting north of
the Coathanger asterism, all climbing higher in the eastern sky.
The background sky here is not crammed with stars, thanks to
all the obscuring dust and gas that together form the Great Rift in
the Milky Way. This will make it easier to locate and follow the
modest magnitude 10 glow of Pallas. Still, you will want to push
the power past 100x in order to separate the pinprick of light
from any nearby stars on the chart. After you find Pallas, shift
your scope east to see the Milky Way spill into view.
With the generally good weather in June, you can likely
observe three evenings in a given block of five, giving you the
chance to watch the night-to-night shift of Pallas. June 9 to 13 is
ideal, since one field of view contains more than a half-dozen
stars to use as reference markers. Just jot down a few points on a
logbook page, then keep coming back to discover which dot has
moved. We’re so far from the path of the Moon that its light will
not bother us.
Pallas is one of the few asteroids with an inclination high
enough to take it well above the throngs orbiting closer to the
ecliptic plane. Heinrich Olbers discovered it by accident in 1802
when it happened to be near Ceres. If not for that, Pallas would
have been found later and assigned a higher number.
Pallas passes the Coathanger (^)
with binoculars 3.5° east of Phi
(φ) Aquarii. Just over a degree
east of this star is a pair of 6th-
magnitude stars roughly
aligned north-south. Another
2 ° farther lies a second 6th-
magnitude star, forming a long
triangle with the previous pair.
Neptune lies a Moon-width
short of this star. For most of
June, it drifts slightly eastward
before reaching a stationary
point June 23.
Uranus lies in Aries the Ram
and rises in the hour before the
onset of twilight. It stands about
10° high June 16, a waning cres-
cent Moon nearby. Uranus, at
magnitude 5.9, lies 10° left of the
Moon and both are visible at
4:30 A.M. local time. In the dawn
sky of June 17, Uranus lies 5°
north of the thinning crescent.
The rapidly advancing twilight
hides Uranus quickly —
viewing improves next month.
Ve nu s leaps into the morn-
ing sky in late June following its
inferior conjunction with the
Sun on June 3. It misses the Sun
by just 0.2°. See how soon after
conjunction you can spot it low
in the east-northeast. By June 18,
Venus lies 11° east of a 27-day
thin crescent Moon. Venus is 4°
high 45 minutes before sunrise
and glowing at magnitude –4.3.
On June 19 the Moon occults
Venus from some regions of the
world, including northwestern
Europe and northern and east-
ern Canada. Its reappearance
from behind the Moon may be
visible from the northeastern
U.S., but challenging due to low
altitude. From Massachusetts,
the Moon rises about 3:55 A.M.^
EDT — and by 4:07 A.M., when
the Moon is 1° high, Venus
begins to reappear. Venus’ disk
is 8 percent lit, and the Moon is
4 percent lit. If the weather
behaves, Massachusetts or
Maine may grab the lucky view.
The pair rise after the reappear-
ance farther west, with the gap
between Venus and the Moon
increasing with longitude.
By June 30, Venus is 8°
high an hour before sunrise,
located near the Hyades star
cluster and 4.5° northwest of
Aldebaran, the 1st-magnitude
star in Taurus the Bull. The
Pleiades (M45) stand 10° above
the planet.
The Moon continues along
the ecliptic to occult the Sun on
June 21 in an annular eclipse
visible from Africa, the Arabian
Peninsula, Pakistan, northern
India, China, and Taiwan.
Greatest eclipse occurs near the
India-China border with a
38-second duration and 99 per-
cent coverage, resulting in a
very thin annular ring. Guam is
10 °
ARIES
June 30 , 1 hour before sunrise
Looking east
Aldebaran
Pleiades
Venus
Algol
Capella
TAURUS
PERSEUS
AURIGA
.
Venus returns to the morning sky (^)
By the end of June, Venus has returned to the pre-dawn sky. On June 30, it is
8° high an hour before sunrise.
just outside the path of annular-
ity and experiences a 98 percent
eclipsed Sun near sunset.
The summer solstice occurs
on June 20 at 5:44 P. M. EDT.
GET DAILY UPDATES ON YOUR NIGHT SKY AT
http://www.Astronomy.com/skythisweek.
SKY THIS MONTH
Martin Ratcliffe provides
planetarium development for
Sky-Skan, Inc., from his home
in Wichita, Kansas. Alister
Ling, who lives in Edmonton,
Alberta, has watched the skies
since 1975.
Tenth-magnitude Pallas spends June in Vulpecula, gracefully arcing past
the famous Coathanger asterism early in the month.

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