Phil Daly explains what you might see in the astronomical sky over Edinburgh and Lothians in the next month.
We retain our parade of 6 planets during the first week of March and witness
the arrival of astronomical spring beginning on the Vernal Equinox. The start
of British Summer Time sees out the month.
The Sun leaves Aquarius (The Water Bearer) on 12 March at 5:36 am and enters
Pisces (The Fishes) and recedes from Earth by 1,252,748 km (0.008 AU) over the
month. Daylight lengthens from 10:43 (10.710 hours) on 1 March to 13:03 (13.044
hours) on 31 March so we lose 2 hours and 20 minutes of night time by the end
of March. The Vernal Equinox occurs on 20 March at 2:46 pm in Pisces (The
Fishes) and astronomical spring will last 92 days, 17 hours and 38 minutes. On
the equinox, sunrise is due east and sunset is due west and day and night are
equal. This is true for every inhabitant of the planet and, in the current
world of grief and uncertainty, it might give a modicum of comfort to think
that such a simple phenomena can be enjoyed by everyone on Earth wherever they
may live.
The Moon begins the month in Cancer (The Crab) and ends in Virgo (The Maiden)
but recedes by 15,222 km. The full Worm Moon makes an appearance on 3 March at
11:38 am in Leo (The Lion). If you are lucky enough to be visiting the Pacific
region on this day, you will witness a total Lunar eclipse. Lunar apogee
(furthest from Earth) that occurs on 10 March at 1:43 pm and takes the Moon to
404,345 km away from Earth—around 19,945 km further than average—subtending
an angle of 29.5 arc-minutes. The Moon enters last quarter on 11 March at 9:39
am in Ophiuchus (The Serpent Bearer). The new Moon appears on 19 March at 1:23
am in Pisces (The Fishes) beginning a new synodic month which will last 29
days, 10 hours and 28 minutes. Lunar perigee (closest to Earth) occurs on 22
March at 11:33 am and finds the Moon some 366,884 km away from Earth—around
17,516 km closer than average—subtending an angle of 32.6 arc-minutes. The
first quarter Moon shows up on 25 March at 7:18 pm in Gemini (The Twins).
There is little in the way of Lunar conjunctions with stars that are visible
from Edinburgh and Lothian this month except for 2. The conjunctions we will
witness are, first, on 27 March in the pre-dawn hours when the waxing gibbous
Moon meets with Pollux in Gemini (The Twins). Second, on 29 March, the same
phase Moon meets with Regulus in Leo (The Lion) in the evening but this will
include a full occultation during civil twilight.
For the inferior planets: Mercury begins the month in Pisces (The Fishes) and
ends in Aquarius (The Water Bearer) but recedes by 20,163,714 km (0.135 AU).
The ‘Swift Planet’ increases in magnitude from 2.03 to 0.44 (4.34 times in
brightness) over the month. Mercury will be lost for observing at inferior
conjunction (in front of the Sun as seen from Earth) on 7 March. On 10 March,
Mercury will be closest to Earth until July. On 20 March, Mercury returns to a
prograde (direct) orbit. Venus begins the month in Aquarius (The Water Bearer)
and ends in Aries (The Ram) but approaches by 13,191,495 km (0.088 AU). The
‘Evening Star Planet’ maintains a bright magnitude of -3.9 over the month. On 8
March, Venus and Saturn will be 0.5 degrees apart as they set in the early
evening.
For the superior planets: Mars remains in Aquarius (The Water Bearer) all month
but approaches by 6,921,566 km (0.046 AU). The ‘Red Planet’ decreases in
magnitude from 1.14 to 1.18 (1.04 times in brightness) over the month. On 26
March, Mars reaches perihelion (closest to the Sun). Jupiter remains in Gemini
(The Twins) all month but recedes by 69,834,672 km (0.467 AU). The ‘Gas Giant’
decreases in magnitude from -2.44 to -2.20 (1.25 times in brightness) over the
month. On 11 March, Jupiter returns to a prograde (direct) orbit as seen from
Earth. On 26 March, Jupiter will be 3.5 degrees south of the waxing gibbous
Moon after sunset and into the evening.
Saturn remains in Pisces (The Fishes) all month but recedes by 10,151,528 km
(0.068 AU). The ‘Ringed Planet’ increases in magnitude from 0.99 to 0.92 (1.07
times in brightness) over the month. Saturn will be furthest from Earth, all
year, on 25 March lying some 1.569 billion km away. Later that day, Saturn
reaches conjunction with the Sun and is lost for observers as the Sun lies
between Earth and planet. Uranus remains in Taurus (The Bull) all month and
recedes by 34,636,471 km (0.23 AU). Uranus decreases in magnitude from 5.75 to
5.80 (1.05 times in brightness) over March. Neptune remains in Pisces (The
Fishes) all month but recedes by 79,196,018 km (0.53 AU). This barely affect
the magnitude of 7.82. The ‘Blue Giant’ reaches solar conjunction on 22 March
and is furthest from Earth, all year, next day lying some 4.62 billion km away.
Our parade of planets (from west-to-east Mercury, Venus, Saturn, Neptune,
Saturn and Jupiter) continues across 130 degrees of azimuthal sky just after
sunset. Mercury will be very difficult to see and Uranus and Neptune will
require a telescope or binoculars. Mercury will be lost in the Sun’s glare
after 7 March.
There are no comets or meteor showers of note this month visible from Edinburgh
and Lothian.
At the time of our sky map, some constellations visible are Ursa Major (The
Great Bear) at zenith, Cepheus (The King) in the north, Bootes (The Herdsman)
in the east, Auriga (The Charioteer) in the west, and Hydra (The Female Water
Snake) in the south. The ecliptic hosts Virgo (The Maiden), Leo (The Lion),
Cancer (the Crab), Gemini (The Twins), Taurus (The Bull) and Aries (The Ram).
Highly visible in the south-west is the ‘Winter Triangle’ comprising the bright
stars Procyon in Canis Minor (The Lesser Dog), Sirius in Canis Major (The
Greater Dog) and Betelgeuse in Orion (The Hunter). Also visible is the much
larger ‘Winter Hexagon’ containing bright stars in 6 constellations: Procyon,
Sirius, Rigel in Orion (The Hunter), Aldebaran in Taurus (The Bull), Capella in
Auriga (The Charioteer) and Pollux in Gemini (The Twins). Circumpolar
constellations—always above the horizon at the latitude of Edinburgh and
Lothian—include Draco (The Dragon), Perseus (The Hero), Cassiopeia (The
Seated Queen) and Camelopardalis (The Giraffe).
