Celestial Events 
by Thomas D. Nicholson 
The Moon The evening crescent 
moon in May should be seen by the 
6th or 7th, passing beneath Pollux and 
Castor (the “twin” stars of Gemini) 
on the 8th. First-quarter moon is on 
the 10th, full moon on the 18th, and 
last-quarter (the morning moon) on 
the 26th. In June, the evening crescent 
will appear on the 5th in Cancer, move 
into Leo on the 6th, and pass very 
close to Regulus on the 7th. By June 
9, the moon is at first-quarter, and 
will be full on June 17, in Sagittarius 
very near the winter solstice. The full 
moon of the 17th is the lowest full 
moon of the year, in the sense that 
it spends the least time and travels 
on the shortest arc in crossing the 
sky from rising to setting. Perigee 
moon (nearest the earth) occurs on 
May 4 and June 1; apogee (farthest 
from the earth) occurs on May 17 
and June 13. 
Stars and Planets Mercury, Venus, 
Jupiter, Saturn, Uranus (after May 
18), Neptune (after June 14), and 
Pluto are in the evening sky; Mars, 
Uranus (until May 18), and Neptune 
(until June 14) are morning stars. Ju- 
piter and Saturn are easily visible from 
dusk until they set after midnight. 
During the early evening, look high 
in the south; the brighter of the two 
is Jupiter (brighter than any other ob- 
ject these nights except the moon). 
Saturn is just slightly to Jupiter’s left. 
Farther still to the left, the bright 
star is Spica, in Virgo. Watch care- 
fully during May and June, and you 
will see Jupiter part slowly from Sat- 
urn as both move away from Spica. 
In June, Jupiter will begin closing the 
gap with Saturn as both planets, re- 
versing their motion through the stars, 
move nearer to Spica. At the end of 
July, Jupiter will pass Saturn in the 
third and last of the “triple conjunc- 
tion” series, which has been taking 
place since January. 
The only other planet in relatively 
good position this month is Mercury, 
going through a favorable evening 
elongation. From mid-May until early 
June, Mercury will be low in the west 
about three-quarters of an hour past 
sundown, looking much like a very 
bright star below the twin stars of 
Gemini (Pollux and Castor). You may 
begin to see Venus, much brighter 
than Mercury, but lower, in the last 
week of May, setting in the sunset 
glow. If so, look above it for Mercury. 
The sun moves from the constel- 
lation Aries into Taurus in mid-May, 
and Mercury, Venus, and Mars move 
along with it through these groups of 
stars, Mercury ending up in Gemini 
in late May and Venus in Gemini in 
early June. Jupiter and Saturn are 
in Virgo, Uranus is in Libra, Neptune 
in Ophiuchus, and Pluto near the bor- 
der between Bootes and Virgo. 
May 3-4: The Eta Aquarid meteor 
shower (up to twenty often bright me- 
teors per hour) reaches maximum on 
the morning of the 4th. 
May 8: The two bright stars above 
the crescent moon tonight are Pollux 
and Castor. 
May 10-11: The first-quarter moon 
is near Regulus in Leo on the night 
of the 10th. It passes the star during 
the day on the 11th and appears east 
of it (to its left) that evening. 
May 13-14: The moon, now in its 
waxing gibbous phase, passes Jupiter 
and Saturn tonight. It moves closest 
to Jupiter at about 10:00 p.m., EST, 
closest to Saturn at about 4:00 a.m. 
on the 14th. It will be readily visible 
as it moves between the two planets 
during the intervening hours. 
May 15: The moon is near Spica, 
the bright star of Virgo, tonight, well 
to the left (east) of Jupiter and Saturn. 
May 19: The bright star tonight 
near the moon, just one day past full, 
is Antares, in Scorpius. 
May 26: Mercury is at maximum 
easterly elongation, its greatest dis- 
tance to the left (east) of the sun. 
This places the planet in its best po- 
sition to be seen as an evening star, 
since it remains above the horizon 
after sundown. Not all elongations are 
equally favorable for viewing the 
planet, but this is a good one since 
Mercury is still fairly high as the sun 
goes down, remaining above the ho- 
rizon into the late twilight, when the 
western sky is dark enough to see it. 
Until the end of May, you can find 
the planet low in the west, below the 
stars Pollux and Castor. 
May 28: Jupiter ends its retrograde 
motion and resumes its direct (eas- 
terly) movement among the stars. It 
now begins to move back toward Sat- 
urn, having last passed that planet 
in February. 
June 3: The new crescent moon may 
be too slim and dim to see tonight, 
but look carefully in the west about 
half an hour after sundown. If you 
can find Venus, look below it, and 
the crescent should be there. 
June 5: Saturn is stationary among 
the stars today, joining Jupiter in re- 
suming its normal easterly motion (to 
the left, relative to the stars around 
it). In another week or so, Jupiter and 
Saturn will be noticeably moving 
closer to Spica (the bright star to their 
left). 
June 9: Mercury is stationary and 
begins to move westerly (retrograde). 
It is in conjunction with Venus today. 
June 9-10: The moon moves past 
Jupiter and Saturn during the morning 
of the 10th. From one night to the 
next, it will shift from the right to 
the left of the two planets. 
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