Sky & Telescope - March 2020 - 47

in March. Venus starts the month in
eastern Pisces, crosses Aries, and ends
the month in western Taurus just a few
degrees below the Pleiades.
Uranus is roughly 2¼° south-southeast of Venus on the American evening
of March 8th, just a few hours after
Neptune is at conjunction with the Sun.

December
solstice

Uranus

Earth

PRE-DAWN AND DAWN

Dusk, March 26 - 28
1 hour after sunset
Moon
Mar 28

Pleiades

Sun
Neptune
Saturn

Mercury

June
Mars solstice

ORBITS OF THE PLANETS
The curved arrows show each planet's movement during March. The outer planets don't change
position enough in a month to notice at this scale.

they're in conjunction with each other
on March 31st (a ﬁne chance to compare their colors).
Mars passes only ¾° south-southeast of much more brilliant Jupiter
on the North American morning of
March 20th. The Red Planet measures
just 6″ across that day (with a decidedly
shadowed edge), Jupiter almost exactly
six times wider.
As Mars crosses the gap between
Jupiter and Saturn, we are treated to the
spectacle of three bright planets in a
line less than 7° long.
Mars lies less than 1° south of
Saturn during the American dawn of
March 31st, with Saturn's globe 16″
across. The rings then span 36″, and like

Jupiter's globe, appear six times wider
than the angular diameter of Mars.
Very challenging to observe is a
much closer conjunction that Mars
has this month. I'm talking about the
Red Planet passing less than 0.02°
south of 14th-magnitude Pluto around
5:15 UT on March 23rd! It's an event
I've waited for since ﬁ rst noticing it
in the printouts from Steve Albers's
breakthrough conjunction computer
program more than 25 years before
Pluto was demoted from planethood.
Sadly, the gap will have widened to
about 10′ by the time the pair rises in
North America, but that's still extraordinarily close.

SUN AND MOON

Venus

Dawn, March 31
1 hour before sunrise
Moon
Mar 27

Jupiter
Saturn

ARIES

CETUS

Sept.
equinox

March
equinox

Jupiter

Mars, Jupiter, and Saturn, west to
east in that order, begin the month
spanning a little more than an hour
in risetimes, all 2 to 3 hours before
sunrise. At month's end, however, the
order is Jupiter, Saturn, and Mars, with
risetimes all occurring within a period
of less than a half hour.
The three planets are east of the
Teapot of Sagittarius, with Saturn and
Mars slipping into Capricornus during the month. Mars is the most active
performer in this drama. It glides east,
overtaking Jupiter just after mid-month
and Saturn on the very last day of
March. Jupiter brightens only from
magnitude -2.0 to -2.1 in March and
Saturn stays at +0.7. But Mars kindles
from +1.1 to +0.8, making it almost
the equal of Saturn in brightness when

Venus

Moon
Mar 26

Looking West

Mars

S A G I T TA R I U S

Looking Southeast

The Sun comes to the March equinox at
11:50 p.m. EDT on March 19th, starting
spring in the Northern Hemisphere and
autumn in the Southern Hemisphere.
The Moon is a waning crescent
forming a dramatic compact triangle
with close-paired Jupiter and Mars 1° to
2° above it on the American morning
of March 18th (Saturn is farther off to
their left). The waxing lunar crescent is
far lower left, almost 10°, of Venus at
nightfall on March 27th, and almost as
far left of Venus the next night.
¢ FRED SCHAAF is the author of The
Starry Room, published 32 years ago by
John Wiley & Sons and republished 18
years ago by Dover Publications.
sskkyyaannddt et el el essccooppee. c. oorm
g * MARCH 2020

http://www.skyandtelescope.org

Sky & Telescope - March 2020

Table of Contents for the Digital Edition of Sky & Telescope - March 2020