Sky & Telescope - February 2024 - 46

FEBRUARY 2024 OBSERVING
Sun, Moon & Planets by Gary Seronik
To find out what's
visible in the sky from
your location, go to
skyandtelescope.org.
Lunar Highs and Lows
The Moon rides the ecliptic, where it encounters several planets and Spica (twice).
THURSDAY, FEBRUARY 1
The Moon meets up with Spica twice
this month, and of the two pairings
the best one occurs early this morning
around 3:30 a.m. EST. Less than 1°
separates the two objects - something
worth setting an early alarm for and
bundling up against the chill of a February
morning. The Moon is a waning
gibbous (just 1½ days past last-quarter
phase) sitting left of the star. When
they next greet each other on the morning
of the 28th, the Moon will again be
a waning gibbous but positioned a little
farther away and to the right of the star.
As noted last month, the Moon and
Spica have some very special meetings
in 2024, including not one but two (!)
occultations - the first in July and the
second in November. Those spectacles
aside, this month's conjunctions are
among the closest the Moon has with
Spica this year and so fall into the
" don't miss it " category.
WEDNESDAY, FEBRUARY 7
The Moon and Venus are separated by
7° as they have their monthly encounter
this morning. For a little bonus
luster, 1.3-magnitude Mars is below and
left of the Morning Star.
Unfortunately, viewing conditions
for this conjunction aren't exactly ideal.
The reason is that the Moon sits just
a few degrees above the southeastern
horizon and at a declination of -28½°.
That's very nearly as far south as it can
get! There are even special terms for
this situation: lunistice, or " major lunar
standstill. " So, what's going on here?
The answer is two things at once. First,
recall that the ecliptic is tilted by 23½°
to the celestial equator. That means that
the ecliptic's northern and southern
extremities have declinations of +23½°
(in Gemini), and -23½° (in Sagittarius).
The second thing is that the
Moon's orbit around Earth is inclined
by 5°. If it reaches the northern extreme
of its orbit at the same time that it
arrives at the northernmost part of the
ecliptic, the two factors add together for
a declination of around +28½°. Similarly,
when the two tilts combine in the
south, the Moon dips to a declination
of -28½°. These tilts coincide every 18.6
years, but the Moon appears unusually
far north or south for several months
before and after the date they max out.
And now is one of those times. When
the Moon rides low on the ecliptic, it's
extra-low and when it's high, it's extrahigh.
The current major lunar standstill
climaxes in January 2025, with the
Moon's declination reaching plus and
minus 28.725°!
These scenes are drawn for near the middle of North America (latitude 40° north, longitude 90° west). European observers should move each
Moon symbol a quarter of the way toward the one for the previous date; in the Far East, move the Moon halfway.
Jan 31 - Feb 2
1 am
Moon
Jan 31
VIRGO
Antares
Moon
Feb 1
Spica
10°
Moon
Feb 5
Dawn, Feb 3 - 6
1 hour before sunrise
SCORPIUS
Moon
Feb 4
Moon
Feb 3
Moon
Feb 2
SAGITTARIUS
Venus
Moon
Feb 7
Looking East-Southeast
46
FEBRUARY 2024 * SKY & TELESCOPE
Looking Southeast
Looking South-Southeast
Looking South
Moon
Feb 6
LUPUS

http://www.skyandtelescope.org

Sky & Telescope - February 2024

Table of Contents for the Digital Edition of Sky & Telescope - February 2024