NATURALIST GUIDED FIELD SEMINARS and tours. 
West Texas and Mexico, Rafting, hiking, backpacking, 
bus University or Continuing Education credit as ap- 
propriate Write Education Department, Chihuahuan 
Desert Research Institute, Box 1334, Alpine. TX 79830 
NATURE PHOTOGRAPHY field work and instruction 
in remote, mountain locations throughout the West 
Brochure The Natural Image, P O Box 45. Wmthrop, 
WA 98862 
NORTH SCOTLAND HIGHLAND WILDERNESS Ex- 
plore, study, interpret the wildlife, vegetation, terrains 
& impact of man on a surpassingly beautiful land 
Small group led by local Scot who knows surfaces 
& depths of his home place 7-14 day programs, 
Apr thru Oct Details Albannach Ltd , Hamilton House, 
Ross & Cromarty, Strathpeffer. Scotland 
OAXACA, MEXICO Unique historical/cultural tour 
Festivals. pre-Hispanic art. Mixtec, Zapotec civiliza- 
tions Oaxaca Club (415) 388-3503 
ORIENTAL ECLIPSE EXPRESS China— Mongolia— Si- 
beria Hong Kong, Nanking, Sian, Peking, Ulan Bator, 
Lake Baikal. Irkutsk, and Bratsk View 31 July 1981 
Solar Eclipse 21 days-$3595 Baylis-Todd Eclipse 
Tour, Claremont Hotel, Berkeley, CA 94705 (415) 
849-4333 
PERU Andean Archaeological trek along Inca Trail 
to Machu Picchu August - Two weeks Small group 
Budget - $985 Write High Country Passage, Box 
1100-NH, Hamilton, Montana 59840 (406) 363-2555 
SAVE ON LUXURY CRUISES' (Passenger ship or 
Freighter) How? Ask TravLtips, 163-09 Depot Road, 
B514, Flushing, NY 11358 
SCOTLAND, ORKNEY, SHETLAND AND ICELAND 
Comprehensive program of nature trips Write Cal- 
edonian Wildlife at McGregor Travel, 33 Lewis Street. 
Greenwich, CT 06830, or toll-free (800) 243-5330 
SINGLE TRAVELERS natural history of the Southwest 
5/2/81 Georgia Island Birdmg & Beachcombing 8/ 
22/81 Maine Wmd|ammer 8/23/81 All Travelers 
Hike-Camp Hawaii 9/26/81 Southwest Photo Work- 
shop 6/21/81 New England Whale Research Ex- 
pedition 9/18/81 Mt McKinley Base Trek 8/7/81 
Blue Sky Adventures, Dept. NH4, Oak Ridge, NJ 07438 
STONE RINGS IN ENGLAND AND SCOTLAND Visit 
over twenty (of the 900!) rings of standing stone 
in the British Isles, including Stonehenge and Avebury 
Time also for castles, churches, cathedrals, and Ro- 
man antiquities Coach tour, July 1-17, 1981 Lyman 
C Peck, (Miami University) 223 Field Crest. Oxford. 
Ohio 45056 (513) 523-2480 
TRAVEL PHOTOGRAPHY WORKSHOP IN SANTA FE 
with Lisl Dennis, author of "How to Take Better Travel 
Photos." HP Books Aug 29-Sept 5 and Sept 5- 
12 PO Box 2847, Dept X, Santa Fe, NM 87501 
WILDERNESS TRAILS IDAHO Backpacking, Ski-tour- 
ing, and Bicycle-touring Come adventure and learn 
with us. Trips for all abilities, everything provided 
We have thirteen years experience and guide only 
in Idaho Write P O 9252 M, Moscow, Idaho 83843 
(208) 882-1955 
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Celestial Events 
by Thomas D. Nicholson 
The Moon Except possibly for a 
brief glimpse of the slim, late crescent 
during dawn on the first of the month, 
don’t expect to see the moon until 
a few nights after the April 4 new 
moon. The earliest view of the thin, 
waning crescent should come on the 
evening of the 7th, with the moon 
in Taurus, between the bright, reddish 
star Aldebaran and the closely packed 
group of stars known as the Seven 
Sisters (or the Pleiades). First-quarter 
moon on April 1 1 will be near Castor 
and Pollux (in Gemini) and full moon 
on April 19 will be near Spica (in 
Virgo). Thereafter, the moon is in the 
morning sky. Last-quarter moon is on 
April 27, new moon in May on the 
5th, and first-quarter on the 10th. 
Stars and Planets Evening planets 
have been scarce so far this year (for 
half of February and most of March 
there was only Mars, which barely 
made it), but this month they come 
back in a stampede. Three planets 
make the transition into the evening 
sky in April (Mercury, Venus, and 
Pluto) and one more in May (Uranus). 
So, even though Mars is going the 
other way (into the morning sky), six 
of the planets will be evening stars 
(above the horizon at sunset) at some 
time during April. 
Despite all the shifting around in 
the morning and evening sky, however, 
only two planets, Jupiter and Saturn, 
are easily visible in April and early 
May. In the morning they are in the 
west, setting during morning twilight. 
To find them, just look for the 
brightest starlike object in the sky. 
That will be Jupiter. The “star” near 
it is Saturn. The next nearest bright 
star (about as bright as Saturn) is 
Spica. Jupiter and Saturn remain close 
to each other throughout April and 
May, although the brighter Jupiter 
separates slowly to the right (west) 
of Saturn. Both planets are moving 
retrograde (westward) relative to the 
stars around them, Jupiter more rap- 
idly than Saturn. You can readily ob- 
serve their movement by comparing 
their positions, night by night, with 
Spica, to their left (east). 
The sun is in the constellation Pisces 
until late in April and then moves 
into Aries. Mercury spends time in 
Aquarius in early April, in Pisces after 
midmonth, and in Aries before the 
end of April. Venus and Mars are 
in Pisces at the beginning of April 
and move into Aries after midmonth. 
Jupiter and Saturn are in Virgo, Ura- 
nus is in Libra, Neptune in Ophiuchus, 
and Pluto is along the border between 
Virgo and Bootes. 
April 2: Mars is in conjunction with 
the sun, leaving the evening sky as 
it shifts to the sun’s morning (right) 
side. 
April 5: Perigee moon (nearest the 
earth) occurs today, about twenty-four 
hours after new moon. The effect of 
perigee will enhance the normally 
strong spring tides that accompany the 
new moon. 
April 7: Venus is in superior con- 
junction (in line with and beyond the 
sun), passing the sun from right to 
left. This takes it into the evening 
sky, where it will be seen in the late 
twilight toward the end of June. 
April 16-17: Tonight will bring an 
exceptional opportunity to watch the 
moon slide past Jupiter and Venus. 
After sundown, the three objects are 
above the eastern horizon, the gibbous 
86 
