Sky & Telescope - February 2023 - 47

+30°
+40°
+20°
+10°
AQUILA
0°
OPHIUCHUS
LIBRA
-10°
Spica
13
Mercury
-30°
-40°
Feb 16
SAGITTARIUS
10 am
8 am
SCORPIUS
6 am
4 am
2 am
Midnight
10 pm
8 pm
6 pm
LOCAL TIME OF TRANSIT
4 pm
2 pm
Antares
CORVUS
HYDRA
CANIS
MAJOR
Sirius
Rigel
ERIDANUS
10
18h
16h
Vega
CYGNUS
HERCULES
14h
12h
BOÖTES
Arcturus
LEO
5 - 6
Regulus
VIRGO
Procyon
ORION
EQUATOR
CANCER
Betelgeuse
TAURUS
Uranus
Feb
23
PISCES
Jupiter
Neptune
Venus
CETUS
Saturn
-20°
-30°
-40°
The Sun and planets are positioned for mid-February; the colored arrows show the motion of each during the month. The Moon is plotted for evening
dates in the Americas when it's waxing (right side illuminated) or full, and for morning dates when it's waning (left side illuminated). " Local time
of transit " tells when (in Local Mean Time) objects cross the meridian - that is, when they appear due south and at their highest - at mid-month.
Transits occur an hour later on the 1st, and an hour earlier at month's end.
Moon-Venus pairings occur later in the
year. Soon after sunset you should be
able to spot a thin, waxing lunar crescent
sitting about 6° below the Evening
Star. Earthshine (sunlight reflecting
off Earth and striking the Moon) will
make the " unlit " portion of the lunar
disk visible as twilight fades. It's a pretty
sight and a reminder not to let " better "
be the enemy of " good. " But better does
arrive tomorrow . . .
WEDNESDAY, FEBRUARY 22
The best conjunction between the
Moon and a planet occurs this evening
when the lunar crescent sits just 1°
left of Jupiter. Compared with Venus,
Jupiter is quite a bit dimmer - magniMoon
Feb
23
Dusk, Feb 21 - 23
1 hour after sunset
PISCES
Moon
Feb 22
Jupiter
Moon
Feb 27
Venus
Mars
Moon
Feb 21
Aldebaran
Looking West
Looking South,
almost overhead
Moon
Feb 26
Dusk, Feb 26 - 27
1 hour after sunset
Pleiades
tude -2.1 versus the Evening Star's -3.9.
The " better " part of this event obviously
comes from the fact that the Moon is
so much closer to its planetary partner.
And, it has to be said, magnitude -2.1
is still pretty bright! But what's really
going to capture your attention isn't
just this tight pairing, it's the threefor-one
spectacle that includes Venus
serving as the apex of a thin, isosceles
triangle that's less than 7½° long. That
triangle includes all three of the brightest
night-sky objects.
The fates of the two planets, however,
are quite different. Venus is early
into its evening apparition and slowly
gaining altitude, while Jupiter is nearing
the end of its current showing and
will gradually slip into twilight's glare
as it marches toward its April 11th
conjunction with the Sun. The gap
between the two planets will continue
to close all month until reaching a
climactic peak on the evening of March
1st when they're just ½° apart. More
about that next month.
MONDAY, FEBRUARY 27
In both December and January, the
Moon passed very close to Mars and
from some locations actually occulted
the planet. It performs that trick again
tonight, but only for observers in
Iceland and northern Scandinavia. For
those of us here in the Americas, we
simply get a very nice close encounter as
the waxing gibbous Moon approaches
to within roughly ½° of the +0.4-magnitude
Red Planet. They'll be closest
around 1 a.m. EST on the morning of
the 28th, and the farther north you
are, the smaller the gap between the
pair will be. From Edmonton, Alberta,
the southern limb of the Moon passes
just 23′ above Mars, but from Houston,
Texas, the gap is more like 37′.
Although the Moon will continue to
TAURUS
visit Mars on a monthly basis for much
of the rest of the year, tonight's encounter
is the final, closest one remaining.
It's also an excellent way to celebrate the
final phase of the current Mars apparition.
The planet reached opposition back
in early December and has been fading
and shrinking ever since. On the 7th
of this month its disk was smaller than
10″, marking the unofficial end of the
Mars telescopic observing season.
¢ Consulting Editor GARY SERONIK
has been keenly watching Mars come
and go since 1971.
sk yand tele scope .o r g * FEBRUARY 2023
47
10h
RIGHT ASCENSION
8h
6h
Castor GEMINI
Pollux
4h
Feb 1
Mars
26 Pleiades
ARIES
+20°
+10°
0°
2h
0h
22h
PEGASUS
+30°
+40°
E
C
L
I
P
T
I
C
DECLINATION

http://skyandtelescope.org

Sky & Telescope - February 2023

Table of Contents for the Digital Edition of Sky & Telescope - February 2023