Howdy Star Gazers and welcome to this episode
of Star Trails. Drew here and I'll be your guide
to the night sky for the week starting June the
15th through the 21st. This week we'll check
in on the moon, a few bright planets, and the
rising galactic core. Then we'll take a step
back in time to explore how ancient cultures
watched and tracked the skies, including the
story of a 2 ,000 year old device pulled from
a shipwreck that turned out to be the world's
first computer. Whether you're tuning in from
the backyard, the balcony, or just your imagination,
I'm glad you're here. So find a cozy spot, let
your eyes adjust, and let's see what the sky
holds for us this week. Let's start with the
moon, since it tends to dominate our evening
sky this week. Tonight the moon is in its waning
gibbous phase, about 87 % illuminated, and rises
a little after sunset. Each night this week,
it'll rise later and later, shrinking as it does.
By Wednesday the 18th, it reaches the last quarter,
looking like a perfect half -circle in the pre
-dawn hours. After that, the moon becomes a waning
crescent, rising in the wee hours of the morning
and becoming harder to spot as it approaches
the new moon on the 25th. One subtle treat arrives
on June 23 when the moon reaches Perigee, its
closest approach to Earth in its monthly orbit,
sitting about 225 ,000 miles away. Perigee also
means slightly stronger ocean tides, and for
the keen -eyed, a slightly larger lunar disk.
The planetary lineup this week spans both dusk
and dawn. Right after sunset, the western sky
gives us two familiar travelers, Mercury and
Mars. Mercury is beginning a brief but favorable
evening sight. On the 15th it appears about 74
% illuminated through a telescope and shines
at magnitude 0 .3, not its brightest, but visible
if you've got a clear, flat western horizon.
Mercury sets about 90 minutes after the sun,
so you'll need to catch it quickly. By June 24th,
it'll be part of a neat lineup with the bright
Gemini twins, Castor and Pollux, hovering just
above the western horizon. If you catch it at
twilight, you'll see Mercury sitting below those
two stars in a graceful vertical line. A little
higher in the sky, Mars is making its slow passage
through the constellation Leo. Its orange glow
contrasts beautifully with Regulus, Leo's bright
blue -white heart star. Look for a close approach
with these objects on the 16th and 17th. The
pre -dawn sky is where the real planetary action
unfolds this week. There you'll find Venus rising
brightly in the east about 90 minutes before
sunrise. At magnitude negative 3 .9, it's the
brightest object in the sky besides the moon
and sun. Just to its upper right, you'll find
Saturn glowing pale yellow in the constellation
Aquarius. On the 19th, the moon will drift nearby
Saturn in the early morning sky, creating a gorgeous
pre -dawn pairing. If you're up around 3 or 4
a .m., it's worth stepping outside for. Jupiter,
on the other hand, is making its quiet exit.
It's low in the west before dawn and gets lost
in the sun's glare by June 24th, when it reaches
solar conjunction. That means it's passing directly
behind the sun from our point of view. It won't
be visible again until it emerges in the morning
sky in mid -July. For telescope users, Uranus
and Neptune are both technically visible, but
they're faint and require effort. Neptune sits
near Saturn in the sky this week, though it's
at magnitude 7 .9 and invisible without optical
aid. Uranus rises before dawn in Aries but remains
difficult to spot until it climbs higher in the
coming weeks. Now let's pull back from the planets
and take in the broader canvas of stars because
this time of year the Milky Way really begins
to show off. By mid -evening, say around 10 p
.m., the Milky Way's bright central band begins
to rise in the southeast. If you're under a dark
sky free from streetlights and urban haze, you'll
see a faint cloudy river of stars running from
horizon to zenith. That's the galactic core,
and June is one of the best times to see it in
the Northern Hemisphere. Overhead, the summer
triangle is fully visible. This prominent asterism
is formed by three bright stars, Vega in the
constellation Lyra, Deneb in Cygnus, and Altair
in Aquila. Vega is the brightest of the three
and nearly directly overhead. Deneb marks the
tail of the celestial swan, and Altair, the eye
of the eagle, flaps along the Milky Way's edge.
Cygnus, also known as the Northern Cross, is
a rich area to explore with binoculars. Look
for clusters, dark nebulae, and star clouds tucked
along the Milky Way's spine. To the west, Boötes
and Arcturus still dominate the early evening.
Arcturus is easy to find. Just follow the curve
of the Big Dipper's handle and arc to Arcturus.
This orange giant star is relatively close, about
37 light -years away, and heading towards us.
Near Boötes, you'll find Corona Borealis, the
northern crown, a small but elegant arc of stars.
And rising later in the east, the teapot -shaped
Sagittarius begins to ascend, marking the gateway
to the galactic center. We're still a few weeks
away from any major meteor showers, but sporadic
meteors can be seen on any clear night. And with
the moon waning towards new this week, darker
skies will make these background meteors even
easier to spot. The summer solstice occurs on
Friday. It's the longest day of the year and
the moment when the sun reaches its highest point
in the sky. The solstice is a reminder of a truth
as old as humanity itself. People have always
looked up. Long before telescopes or scientific
journals, humans were watching the sky, tracking
its rhythms and embedding its stories into stone,
memory, and myth. The solstices, both summer
and winter, acted as celestial bookmarks for
ancient cultures, fixed points in the rhythm
of the seasons. From the Arctic Circle to the
Andes, they marked time by the sky, planting,
harvesting, hunting, and praying according to
the movements of the sun, moon, and the stars.
Let's begin in prehistoric Europe, where monuments
like Stonehenge align almost precisely with the
rising sun on the summer solstice. When sunlight
breaks over the heelstone and pours into the
monument's center, it creates a striking visual
that likely held spiritual, agricultural, or
communal meaning. Constructed in several phases
between roughly 3000 and 2000 BCE, Stonehenge
incorporated massive rock formations transported
from more than 150 miles away in Wales. Beyond
solstice alignments, theories suggest Stonehenge
may have functioned as a burial ground, ceremonial
center, or a lunar calendar. Similar alignments
appear in Ireland and Orkney, where solar events
dictate how light enters stone passageways at
exact times of year. These early engineers didn't
use metal tools or mathematics as we know them,
but they built with precision, using horizon
markers and the human eye to measure time itself.
Across the world in Mesopotamia, the Babylonians
were developing what we might recognize as the
first scientific astronomy. They recorded the
rising and setting of stars, tracked eclipses,
and used a base 60 number system that still influences
how we measure time today. They also discovered
the Saros cycle, an 18 -year period after which
lunar and solar eclipses repeat. All of this
was done without lenses, telescopes, or even
basic optics. Their most sophisticated tools
were observation, record -keeping, and patience.
But for sheer ingenuity, few artifacts of the
ancient world rival the Antikythera mechanism.
Pulled from the sea off the coast of Greece in
1901, this corroded mass of bronze gears remained
a mystery for more than a century. Today, we
know it to be an ancient computer. a mechanical
device designed around 100 BCE to track the motions
of the sun, moon, and five known planets. It
even predicted eclipses and synchronized with
the Olympic games. Recent studies revealed it
used differential gearing and a sophisticated
epicyclic model to account for the moon's elliptical
orbit. a level of mechanical sophistication not
seen again until the 18th century. Its back dials
also recorded the metonic cycle, that's a 19
-year cycle in which lunar phases recur at the
same time, and eclipse predictions using Babylonian
-style glyphs. It's the only device of its kind
ever found suggesting a lost tradition of high
-precision astronomical engineering in the Hellenistic
world. The Greeks also gave us some of the earliest
theoretical frameworks for understanding the
sky. Aristarchus proposed a heliocentric model
of the solar system around the 3rd century BCE,
nearly 1800 years before Copernicus. Hipparchus,
often called the father of trigonometry, developed
the first comprehensive star catalog and discovered
precession. That's the slow wobble in Earth's
axis. And of course Ptolemy's geocentric model,
though incorrect, dominated astronomical thought
for more than a millennium, owning to its mathematical
sophistication and explanatory power. These thinkers
were beginning to shift astronomy from observational
tradition into formal science. Over in ancient
China, astronomers during the Shang dynasty and
later eras kept detailed records of comets, eclipses,
and planetary motions. They identified guest
stars, what we now know as supernova, and connected
celestial events to the Emperor's legitimacy.
Royal astronomers operated with high stakes.
Failing to predict an eclipse would cause political
unrest or even cost them their lives. The Chinese
were also among the first to document phenomena
like Halley's Comet, and their star charts helped
preserve sky positions across centuries. In the
Inca Empire, solar observation was central to
statecraft. Temples like Machu Picchu were aligned
with solstices, and ritual pillars were believed
to hold the sun in its proper path. Likewise,
Mayan kings scheduled battles and ceremonies
according to the Venus cycle. The Dresden Codex,
one of the few surviving Mayan texts, contains
incredibly precise Venus tables. Its appearances
and disappearances were used to guide warfare.
coronations, and sacrifices. Islamic scholars
preserved and expanded on Greek knowledge. They
developed astrolabes, improved star catalogs,
and calculated planetary orbits with remarkable
precision. And speaking of star maps, some of
the most astonishing weren't drawn at all. They
were sung. The Polynesians, navigating vast stretches
of the Pacific, memorized the rising and setting
points of stars to guide them between islands
that were thousands of miles apart. Without metal
tools or written maps, they used oral knowledge,
wave patterns, bird behavior, and the stars to
sail across the world's largest ocean. Their
star compass divided the horizon into more than
30 sectors each marked by a key star. This mental
map was passed down through chance, ritual, and
experience. We also see astonishing sky knowledge
in indigenous cultures of North America and Australia.
The Navajo, Lakota, and other Native American
nations wove constellations into their moral
teachings. agricultural cycles, and healing practices.
In some traditions, the Milky Way was seen as
the path of souls or a great river in the sky.
What kind of tools made all this possible? Most
ancient astronomers relied on naked eye observation
and simple but clever instruments. One such instrument
was the nomen, a stick planted vertically in
the ground that could track the Sun's shadow
to measure time and solstices. Egyptians used
plumb lines and the stars to align structures
and keep time at night. The armillary sphere,
quadrant, and water clocks were used by Greeks,
Chinese, and Arabs to refine measurements. Of
course, the stars weren't only mapped, they were
mythologized. Cultures around the world gave
names and stories to the constellations, turning
the night sky into a canvas of meaning. The Pleiades,
or Seven Sisters, appear in Greek, Japanese,
and Aboriginal lore. The Greek version of Orion
the Hunter is mirrored in myths from the Americas
and Africa, often with similar traits. Chasing.
boasting or falling. The Inuit interpret Orion
as a caribou hunter. The Greeks imagined Scorpius
chasing Orion, which is why they appear on opposite
sides of the sky. And the Milky Way itself might
be a road, a river, a trail of birds, or the
backbone of night, depending on where you're
standing. The night sky is part calendar, part
compass, and part sacred text. And maybe that's
the biggest through line of all. Ancient astronomy
wasn't some esoteric discipline. It was life.
Watching the sky meant understanding your place
in time, your duties to the community, and your
connection to something larger than yourself.
So today, when we glance at an app to check the
phase of the moon or use GPS to navigate a back
road, It's easy to forget how deep our relationship
with the sky runs. But every time we look up,
we're tapping into an ancient tradition. One
that crosses borders, bridges millennia, and
ties us to the people who built stone circles,
carved eclipse charts into clay, or sang the
constellations into memory. We're not just watching
the sky. We're participating in humanity's oldest
shared story. If the stars spoke to you this
week, or if a question's been on your mind, I'd
love to hear it. Visit our website, StarTrails
.Show, where you can contact me and explore past
episodes. Be sure to follow us on Mastodon, Blue
Sky, and YouTube. Links are in the show notes.
Until we meet again beneath the stars, clear
skies everyone.