Abrams Planetarium Skywatcher's Diary
May 1998
To the reader
The Skywatcher's Diary for May 1998 has been prepared
by Robert C. Victor. Credit to the author and to Abrams Planetarium, Department
of Physics and Astronomy at Michigan State
University, and mention of our Sky Calendar, would be appreciated.
A sample recent issue of the Sky Calendar is available
over the Internet. It can be viewed via a World-Wide Web browser at
http://www.pa.msu.edu/abrams/SkyCalendar/Index-t.html
Our May 1998 issue may be reprinted for free
distribution on National Astronomy Day, Saturday, May
2.
If you would like a printed sample of the May issue, send a long,
self-addressed stamped envelope to:
May Sky Calendar
Abrams Planetarium
Michigan State University
East Lansing, MI 48824
Each month, the Department of Physics and Astronomy at Michigan State
University also makes Skywatcher's Diary available over the Internet.
It can be accessed with a World-Wide Web browser at
http://www.pa.msu.edu/abrams/SWD/Diary.html
The Skywatcher's Diary is also available via anonymous ftp at:
ftp://www.pa.msu.edu/pub/swd/
Morning Planets: Throughout May, Venus and Jupiter are prominent in
E to ESE an hour before sunrise. Venus is brighter, to lower left of
Jupiter. They are 8 degrees apart on May 1, 15 degrees apart on May 9.
Their separation widens by 1 degree per day, to 20 degrees on May 14,
25 degrees on May 19, 30 degrees on May 24, 35 degrees on May 29,
40 degrees on June 3. Mercury rises in bright twilight 16 or 17 degrees
lower left of Venus May 1-15. Despite Mercury's attaining greatest
angular distance from the Sun for this year on May 4, it is hard to see
from mid-northern latitudes; viewers in N states will need binoculars to
see Mercury during this horizon-hugging appearance. Saturn emerges,
passing only 1 degree from brighter Mercury on May 12 and 13, but
watchers in N states must wait until several days later before Saturn
becomes visible with unaided eye. Look for Saturn to lower left of
Venus, by 10 degrees on May 19, decreasing to within 5 degrees on
May 24. The waning crescent Moon sweeps by four planets, in order,
Jupiter, Venus, Saturn, and Mercury, May 20-24. As depicted on Sky
Calendar, Moon leapfrogs Jupiter on May 20-21, approaches Venus on
May 22, and is 2 or 3 degrees below Saturn May 23. A glimpse of the
old Moon on May 24 in bright twilight just 3 or 4 degrees lower right of
Mercury is reserved for southern viewers. Venus and Saturn appear
within 5 degrees apart on ten consecutive mornings, May 24-June 2.
Binoculars give rewarding views of Venus and Saturn in same field
May 24-June 2, about one hour before sunup. The Venus-Saturn pair
appears closest May 28 & 29.
Skywatcher's Diary: May 1998
Friday, May 1
At dusk, locate the fat crescent Moon in the western sky, with the bright
star Procyon 12 degrees to its lower left, and Pollux in Gemini almost
as far to Moon's upper right. Castor, the fainter Gemini twin, is 4-1/2
degrees right of Pollux.
This Friday and Saturday, MSU Observatory will be open for public
viewing from 9:00 until 11:00 p.m. if skies are clear. Telescopes and
binoculars provide stikingly detailed views of the lunar landscape,
especially near the Moon's terminator (day-night boundary). Tonight the
crater Theophilus is in excellent view.
Milky Way Legacy continues 8:00 p.m. tonight at Abrams Planetarium.
Tour our amazing home galaxy with noted author Ken Croswell and
emerge with a clearer view of our home in space. Find out some of the
ways the Milky Way is very special, and how, unlike most galaxies, it
is equipped to create the variety of ingredients needed for life.
Showtimes are Fridays and Saturdays at 8 p.m., Sundays at 4 p.m.,
through August 2.
Saturday, May 2
Today is National Astronomy Day. Check with your local planetarium
or astronomy club, and join in on their activities. For events at Abrams
Planetarium and MSU Observatory, see Fri. May 1.
About 1-1/2 hours after sunset, using binoculars, locate the Beehive
cluster within 5 degrees to the Moon's upper right. The Moon is
approaching First Quarter phase (90 degrees or one-quarter circle east of
the Sun) and is nearly half full.
Sunday, May 3
Our family show, WSKY ... Radio Station of the Stars, is presented
Sundays at 2:30 p.m. at Abrams Planetarium.
An hour after sunset, Regulus, marking the heart of Leo the Lion, is
high in SSW, about 9 degrees to Moon's upper left. Look again at the
same time on Monday. These evenings the reddish first-magnitude star
Aldebaran, eye of Taurus, is low, about 15 degrees N of due west, but
it's getting lower each night and will soon disappear for the season.
An hour before sunrise on Monday, the two brightest objects are low,
between E and ESE: Venus, with Jupiter about 10 degrees to its upper
right. About 15 minutes later, use binoculars to watch for Mercury
rising just north of east and nearly 17 degrees lower left of Venus. On
Monday, Mercury appears farthest from the Sun, 27 degrees, but from
northern U.S. it rises in bright twilight and is difficult to see. In poor
apparitions such as this one, Mercury is noticeably higher and easier to
see from southern states.
Monday, May 4
Moon is about two-thirds full at dusk. Note star Regulus 3 or 4 degrees
to its upper right.
Tuesday, May 5
The Moon is in S about an hour after sunset. Note Regulus, heart of
Leo, 15 degrees to its upper right, and Denebola, the Lion's tail, nearly
as far to Moon's upper left.
Wednesday, May 6
On Thursday, about 45 minutes before sunrise, brilliant Venus lies low,
just south of due east, with Jupiter 13 degrees to its upper right.
Mercury has just risen just N of due east, and 16 degrees to Venus'
lower left. This is as close as Mercury gets to Venus during the current
apparition of Mercury. In Mercury's next morning appearance, in late
August and early September, these planets will appear within 3 degrees
of each other for three weeks.
Thursday, May 7
An hour after sunset, locate Spica in SE, 15 degrees to Moon's lower
left. Spica marks the ear of corn or spike of wheat in the hand of Virgo.
Friday, May 8
Locate the first-magnitude star Spica just lower right of the Moon at
dusk. For most of the night, until Spica sets, Moon and star remain
within 5 or 6 degrees apart.
Saturday, May 9
Tonight at dusk, Spica lies about 10 degrees to Moon's upper right.
An hour before sunup on Sunday, find Venus low in east with Jupiter
16 degrees to its upper right. As the sky brightens, use binoculars to try
for Mercury 16 degrees to Venus' lower left. Even harder to see is
Saturn, 3 degrees to Mercury's left and a little lower.
Sunday, May 10
The Moon is up all night tonight, rising before sunset on Sunday, and
setting soon after sunrise on Monday. Approaching Full, the Moon
slips between the 3rd-magnitude stars Alpha and Beta in Libra
overnight. At dawn on Monday, faint Saturn appears 2 degrees left of
Mercury. Look on horizon, north of east, 16 to 18 degrees lower left of
Venus.
Monday, May 11
The Moon, just past Full, rises in ESE shortly after sunset. From a
place with an unobstructed view toward ESE, note Moon's red color
and flattened shape just as it rises.
On Tuesday about 45 minutes before sunrise, two bright planets are in
clear view between E and ESE: Brilliant Venus with Jupiter 18 degrees
to its upper right. Using binoculars, look for Mercury and fainter Saturn
near horizon 17 degrees to Venus' lower left. On both Tuesday and
Wednesday mornings, Mercury and Saturn are 1 degree apart; on
Tuesday Saturn is to upper left of Mercury, and on Wednesday it's
almost directly above Mercury.
Tuesday, May 12
Mars is hidden behind the Sun's disk today, and will emerge into
morning twilight during July. Rising farther ahead of sunup each day,
Mars will be up all night in late April 1999. Tonight, the Moon rises in
ESE about an hour after sunset. Wait another 1-1/2 hours, and look low
in SE for reddish first-magnitude Antares, heart of the Scorpion, 9
degrees lower right of the Moon. Moon and Antares remain about the
same distance apart for the rest of the night, with the star almost directly
below the Moon as dawn brightens.
Wednesday, May 13
About 45 minutes after sunset, can you still see the Winter Triangle? It
is nearly equilateral, and consists of Sirius very low in WSW, Procyon
26 degrees above it, and Betelgeuse low in the west. Tonight the Moon
rises in ESE about 2 hours after sunset.
Thursday, May 14
An hour after sunset, after Sirius sets, the three brightest stars visible are
yellow-orange Arcturus high in ESE, blue-white Vega low in NE, and
yellowish Capella in NW.
Friday, May 15
An hour after sunset, notice Vega low in NE with Deneb 24 degrees to
its lower left. In another two hours, Altair is visible low in E,
completing the Summer Triangle.
Saturday, May 16
At this time of year, the Big Dipper is high in the north as the evening
sky darkens. Follow the Dipper's handle to two bright stars: "Follow the
arc to Arcturus and drive a spike to Spica".
Sunday, May 17
In the evening sky, Arcturus and Spica are 33 degrees apart. To their
west and 35 degrees from each, is the 2nd-magnitude star Denebola,
marking the tail of Leo, the Lion. The figure formed by connecting
Arcturus, Spica, and Denebola is sometimes called the Spring Triangle.
Monday, May 18
An hour before sunrise each day this week, a lineup of four bright solar
system objects is visible. On Tuesday, the Last Quarter Moon, half full,
is in SE, with Jupiter in ESE 22 degrees to Moon's lower left. Brilliant
Venus is low in E, 25 degrees lower left of Jupiter. Finally, Saturn on
Tuesday is 10 degrees lower left of Venus, and appears one degree
closer to Venus each day. Look each morning this week as Moon
passes all three planets.
Tuesday, May 19
On Wednesday an hour before sunup, the two brightest planets are
Venus, low in E, and Jupiter in ESE. The fat crescent Moon is about 8
degrees upper right of Jupiter. Saturn is very low, 9 degrees lower left
of Venus.
Wednesday, May 20
In the ESE an hour before sunrise on Thursday, the waning crescent
Moon has Jupiter about 6 degrees to its upper right. Low in east, Venus
has Saturn 8 degrees to its lower left.
Thursday, May 21
An hour before sunrise on Friday, four solar system bodies span an arc
of just 35 degrees in the eastern sky. In order from upper right to lower
left, they are Jupiter in ESE, and the Moon, Venus, and Saturn low in
the east. Other bright objects visible are the Summer Triangle,
consisting of Vega and Deneb nearly overhead and Altair high in the
south; golden Arcturus in the west; and reddish Antares very low in the
southwest.
Friday, May 22
Last easy chance to see the old crescent Moon: On Saturday an hour
before sunrise, look for the slender crescent very low, 8 degrees north
of due east and about 7 degrees lower left of brilliant Venus. Look for
Saturn within 3 degrees above the Moon and 6 degrees lower left of
Venus. Jupiter is 29 degrees to Venus' upper right. Although the Moon
will be gone from the morning sky next week, continue tracking the
planets!
Saturday, May 23
On Sunday morning, an hour before sunrise, find Venus in east with
Jupiter 30 degrees to its upper right, and Saturn 5 degrees to Venus'
lower left. Venus-Saturn will be no farther than 5 degrees apart through
June 2. From Gulf Coast states to southern California and Hawaii, the
Moon might be visible as sunrise approaches. Using binoculars 45
minutes before sunup, can you spot Mercury rising 21 degrees to
Venus' lower left? If so, wait 15 minutes more, then try for the very thin
old Moon 3 or 4 degrees to Mercury's lower right.
Sunday, May 24
An hour after sunset, the brightest stars visible (not in order of
brightness) are: the arch of four stars in W to NW marked from left to
right by Procyon, Pollux, Castor, and Capella; Vega and Deneb in NE;
Arcturus and Spica in SE, and Regulus in Leo in SW.
Monday, May 25
The Moon is New today at 3:32 p.m. EDT and is not visible.
Tuesday, May 26
Half an hour after sunset, look for the slender crescent young Moon
very low in WNW.
On Wednesday an hour before sunup, Venus is very low, a few degrees
north of due east. Jupiter is in ESE 33 degrees to Venus' upper right.
Saturn is 1.7 degrees to Venus' lower left. Mornings for the rest of May
will be interesting for planet viewing. Look daily.
Wednesday, May 27
An hour after sunset, the crescent Moon, low in WNW, displays
earthshine on its dark side. Note Pollux and Castor 20 degrees above,
and Procyon 22 degrees to upper left.
The Venus-Saturn pair, low in east an hour before sunup, appears
closest this Thursday and Friday mornings. From the East Coast,
Venus-Saturn are 0.7 degree apart on May 28, and 0.5 degree apart on
May 29. From the West Coast, they're 0.6 degree apart both mornings.
From Hawaii, they're within 0.5 degree on May 28, and 0.7 degree apart
on May 29. Binoculars give a very rewarding view of the close pair.
Jupiter is 34 or 35 degrees to the pair's upper right.
Thursday, May 28
An hour after sunset, bright Procyon is low in west, 13 degrees to
Moon's lower left. Plollux, the brighter Gemini twin, is 11 degrees to
Moon's upper right, and Castor, the other twin, is 4-1/2 degrees right of
Pollux.
Don't miss Friday morning's close pairing of Venus and Saturn, low in
east an hour before sunrise. [See May 27.]
Friday, May 29
This Friday and Saturday, MSU Observatory will be open for public
viewing from dusk until 11:00 p.m. if skies are clear. Telescopes and
binoculars provide stikingly detailed views of the lunar landscape,
especially near the Moon's terminator (day-night boundary).
Milky Way Legacy continues 8:00 p.m. tonight at Abrams Planetarium.
Tour our amazing home galaxy with noted author Ken Croswell and
emerge with a clearer view of our home in space. Find out some of the
ways the Milky Way is very special, and how, unlike most galaxies, it
is equipped to create the variety of ingredients needed for life.
Showtimes are Fridays and Saturdays at 8 p.m., Sundays at 4 p.m.,
through August 2.
Now spreading farther apart each day, Venus and Saturn are still only
1.5 degrees apart an hour before sunup on Saturday morning, and just
over 2.5 degrees apart on Sunday. You may recall that Venus passed
close to Jupiter in the morning sky on April 23. On the next occasion
that Venus will pass Jupiter and Saturn, the pairings will be seen in the
evening sky, on February 23 and March 19 in 1999.
Saturday, May 30
At dusk, look for Regulus in WSW, to Moon's upper left. Check again
on Sunday.
Sunday, May 31
Our family show, WSKY ... Radio Station of the Stars, continues at
Abrams Planetarium, Sundays through August 2, at 2:30 p.m.
An hour after sunset, notice the first magnitude star Regulus, heart of
Leo, closely above or upper right of the fat crescent Moon. Look hourly
tonight until they sink low in the western sky, and follow the Moon's
motion past the background star. From lower Michigan, the Moon's
northern cusp (point of the crescent) will miss the star by less than 1-1/2
degrees.
