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GUIDELINES
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CALIFORNIA WILD
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Skyguide
January to March 1999
Bing
F. Quock
| January
1 |
Full Moon. The moon appears larger
than it really is as it rises: this is known as "the Moon Illusion." |
| January
3 |
Earth at perihelion, its closest point
to the Sun–a distance of 91,405,800 miles (147,096,600 kms). |
| January
4 |
Peak of the Quadrantid meteor shower,
which averages about 40 meteors per hour. Unfortunately, the bright
light of the waning gibbous Moon will probably interfere with observations.
However, with the Moon entering the stars of Leo, you can still watch
as it slowly approaches the bright star Regulus during the night. |
| January
31 |
"Blue Moon." This is the
second Full Moon in the same calendar month, since the Moon's cycle
of phases is shorter than 30 days. In truth, nothing happens to the
Moon's color. |
| February
3 |
Mercury at superior conjunction, or
located on the other side of the Sun from Earth. Being in line with
the Sun, it is not visible in our star's bright glow. |
| February
15 |
New Moon. An Annular Solar Eclipse
is visible from Australia. |
| February
22 |
First Quarter Moon in Taurus, due south
at sunset. Look nearby for the bright red star Aldebaran, the Bull's
glaring eye. Look with binoculars along the dividing line between
the Moon's daytime and nighttime sides for the shadows of craters
and mountains. |
|
March 1
|
Full Moon for the Pacific Time Zone.
For most of the U.S. (and on printed calendars) the Full Moon is on
March 2. |
| March
3 |
Mercury at greatest eastern elongation,
easily visible in the west at sunset. |
| March
17 |
New Moon. Not visible, but Venus and
Saturn are striking in the west after sunset. In two days, the crescent
Moon will join them, forming a commanding triplet. |
| March
20 |
Vernal Equinox, or beginning of spring, at 5:47 p.m.The Sun rises
due east and sets due west–theoretically above and below the horizon
for the same length of time. For people south of the equator, this
is the first day of Autumn. For people on the equator, the Sun crosses
directly overhead at noon.
|
| March
31 |
Full Moon, another Blue Moon. Didn't
this already happen in January? See the box. |
Planets
Mercury
A good year for Mercury-watchers. Our best opportunity to glimpse it this
quarter will be between February 23 and about March 11, when it is at
its greatest eastern elongation (or angular separation) from the Sun.
It'll be visible low in the west just after sunset, and some interesting
planetary configurations will make it easy to locate. On February 23,
look about 10 degrees below and slightly to the right of the striking,
close pair of Venus and Jupiter (10 degrees is about the height of your
fist held at arm's length). During the following days, as Venus and Jupiter
separate, Jupiter will descend toward the horizon and approach Mercury.
On March 7, Jupiter and Mercury will form a line parallel to the horizon,
with Jupiter on the left and fainter Mercury on the right.
Venus
In January, this brilliant planet can be seen briefly in the evening sky,
setting in the southwest soon after the Sun. Gradually, as its angular
separation from the Sun increases, it'll be seen higher and higher in
the sky after sunset, its dazzling brightness making it hard to miss.
On February 23, look for Venus and Jupiter in the year's closest planetary
conjunction. For the next few days after that, you can see Mercury, Venus,
Jupiter, Saturn, and the Moon in the sky at the same time, just after
sunset.
Mars
In January, Mars rises at about midnight, located against the stars of
Virgo. On February 20, it crosses into Libra, and on March 18, stops its
slow, eastward crawl and begins moving back toward the west, beginning
what is called a "retrograde loop." By March, it rises about
two hours before midnight. On the morning of January 9, look toward the
south–south-east before dawn to see Mars, the Moon, and Virgo's brightest
star, Spica, clustered together. The Moon passes close again on the mornings
of February 7 and March 7.
Jupiter
Our solar system's largest planet slowly moves westward into the Sun's
glow, disappearing by late March. Until then, you can see it in the evening
sky, encountering the crescent Moon on January 21 and February 17, Venus
on February 23 (spectacular!), and Mercury on March 5.
Saturn
Following Jupiter toward the glow of the Sun, Saturn lounges against the
faint stars of Pisces, crossing the boundary into Aries just as March
ends. Located in an area devoid of bright stars, it is easy to pick out.
The Moon sweeps past on the evenings of January 23, February 19 and 20,
and most strikingly on March 19, when the Moon and Saturn are clustered
with brilliant Venus.
| |
Sunrise |
Local Noon |
Sunset |
| January 1 |
7:25 A.M. PST |
12:13 A.M. PST |
5:02 P.M. PST |
| February 1 |
7:14 A.M. PST |
12:24 P.M. PST |
5:33 P.M. PST |
| March 1 |
6:41 A.M. PST |
12:22 P.M. PST |
6:03 P.M. PST |
| April 1 |
5:55 A.M. PST |
12:14 P.M. PST |
6:33P.M. PST |
| |
(Times
are for San Francisco, CA) |
| A Moonless February? |
|
January and March of this year both have what have come to be known
as "Blue Moons"--that is, two full moons in the same calendar
month. One occurs at the very beginning of each month and the other
at the end. Technically this leaves February without a full moon,
though on the 1st and 28th, it'll look close enough to full that
most people won't think anything of it. February usually has only
28 days, and since the moon's cycle of phases is 29 1/2 days long,
there's always some part of the lunar cycle that doesn't occur during
February although it isn't often the full moon.
Noting that this same rare coincidence occurred in 1866, cartoonist
Robert Ripley (creator of "Believe It or Not!") declared
the second month of that year to be "the Month without a Moon,"
implying the moon had not been seen at all that February. He also
claimed that such a phenomenon wouldn't happen again for 2.5 million
years. In fact, after 1999, the next February without a full moon
will be 2018...believe it or not!
|
Bing
F. Quock, Morrison Planetarium
bquock@calacademy.org
|
Winter 1999
Vol. 52:1
|
