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Hunting the Hunter: Orion’s Myth and Marvels · Star Trails: From Backyard Astronomy to Cosmic Wonder

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Howdy star gazers and welcome to this episode of Star Trails.
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I'm Drew and I'll be your guide to the night sky for the week starting January 26th through
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February 1st.
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This week's winter sky offers up some familiar favorites and with Orion prominent in the
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sky we're going to take a closer look at the celestial treasures of this familiar constellation.
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I'll tell you how to find its notable nebula and will tour its brightest stars.
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So grab a comfortable spot under the night sky and let's get started.
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We begin this week with the moon in a waning crescent phase with the new moon arriving
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on January 29th.
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The moon is essentially invisible making this an excellent period for deep sky observations.
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There's still a bit of a parade of planets happening.
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You aren't likely to catch Mercury as it's very close to the sun, but Venus and Saturn
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are still dominating the southwest sky just after dusk.
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Look for Venus, the brightest object in that portion of the sky, with Saturn a good bit
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dimmer hanging out below and to the left.
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Saturn's rings look amazing right now and you should be able to make out its moon, Titan,
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and even some cloud bands with a decent instrument.
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Look towards the south to catch Jupiter already rising high after dusk.
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It will be visible in Taurus near the red star Aldebaran until about 3am when it finally
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dips below the western horizon.
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A keen observer may be able to spot a moon or two with good binoculars, but in a small
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telescope you should be able to see all four Galilean moons along with some cloud bands
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on the Jovian surface.
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The real standout continues to be Mars.
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Having reached opposition the week before last, it's still big and bright in Gemini.
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Look for it as a bright, ruddy star near Caster and Pollux.
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If you can observe it with a higher powered scope, you're likely to see a polar ice cap
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in contrast to its red color.
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We often mention several of the prominent constellations, Orion, more on him later,
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Gemini and Taurus.
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For something different, check out Canis Major, the big dog, and Canis Minor, the little dog.
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Canis Major is low in the southeast in the early evening, but will rise throughout the
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night.
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Follow Orion's belt of three stars downward until you see a bright star.
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That's Sirius, the brightest star in our night sky.
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The deep sky object, M41, is also located nearby.
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It's an open cluster just southeast of Sirius and is a good target in binoculars.
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Look roughly 10 degrees to the west of Sirius to encounter Procyon, a bright star in Canis
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Minor forming the winter triangle with Sirius and Betelgeuse.
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It's hard to think of a more recognizable constellation than Orion.
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With its three distinct belt stars and easily recognizable shape, it's a familiar sight
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in the winter, even to non-astronomers, who are probably familiar with at least some of
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its lore.
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Known to many cultures as a mighty hunter or warrior, Orion is a treasure trove of astronomical
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marvels.
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From brilliant stars on the verge of stellar death to newborn suns still swaddled in glowing
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nebula.
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We'll journey through the mythological roots, the bright stars, the sprawling nebula, and
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the star-forming secrets of this mighty constellation.
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Orion has captured imaginations for millennia.
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In Greek mythology, Orion was a gifted hunter.
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So skilled, he boasted he could slay every creature on Earth.
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Depending on the version of the legend, his fate was sealed by a scorpion sent by the
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Earth Goddess Gaia, or by Artemis, in a tragic twist of events.
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In many retellings, Orion and Artemis shared a mutual love of hunting and became companions.
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Some versions of the story hint at a romantic or at least a very close bond, one that concerned
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Apollo, Artemis' brother, who worried Orion might threaten Artemis' vow of chastity.
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In one account, Apollo tricked Artemis into shooting an unidentified figure swimming far
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out at sea, claiming it was a villain she needed to slay.
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Only after losing her arrow did Artemis realize she'd killed Orion.
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In other versions, Gaia, or Earth, grew angry at Orion's boast that he could kill every
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animal, and she sent a scorpion to dispatch him.
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This scorpion killed Orion, and Artemis placed him among the stars to honor his hunting prowess
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and her fondness for him.
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In the sky, Scorpius, the scorpion, now rises in the east just as Orion sets in the west,
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ensuring the two never share the heavens.
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Many other cultures also recognized Orion's distinctive pattern, the ancient Egyptians
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associated Orion's belt with the god Osiris, and the three stars of the belt relinked to
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the pyramids on the Giza Plateau.
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In China, parts of Orion formed various asterisms used in astrology and folklore, while the Norse
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saw Orion as a reminder of their heroic tales.
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Let's survey the brightest stars of Orion.
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Beetlejuice, or Alpha Orionis, marks Orion's shoulder.
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It's a red supergiant more than 700 times the diameter of our sun, and among the largest
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visible stars in the night sky.
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Beetlejuice is nearing the end of its life, destined to explode as a supernova, though
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it could be in a hundred thousand years or more.
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Its brightness is also variable, sometimes it dims noticeably, reminding us that star
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behavior can be surprisingly dynamic.
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Directly opposite Beetlejuice in Orion's foot, or knee, is Rigel, Beta Orionis, a blue-white
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supergiant.
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Despite its beta designation, Rigel is often the brightest star in Orion.
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It emits tens of thousands of times more light than our sun and represents a star still burning
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its fuel at a furious rate.
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Rigel's intense luminosity makes it a valuable anchor for navigators in the southern hemisphere.
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Bellatrix, Gamma Orionis, or the Amazon star, is another blue giant, though smaller and
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dimmer than Rigel.
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It forms Orion's other shoulder.
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The name Bellatrix translates from Latin as Female Warrior, which seemingly conflicts
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with Orion's masculine persona.
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No one really knows why, but over centuries astronomers adopted a grab bag of ancient
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medieval and Renaissance naming conventions, and perhaps ages ago, this star's relationship
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to Orion wasn't perfectly aligned with the Greek mythos.
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At the lower right corner of the constellation, diagonally opposite Beetlejuice is Syif, Kappa
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Orionis, another brilliant blue supergiant.
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Though it shines less brightly to the naked eye than Rigel, Syif's luminosity is enormous
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by stellar standards, just partially veiled by distance and interstellar dust.
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But perhaps the most famous part of Orion is the trio of stars that form his belt.
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Alnatak, Alneelum, and Mentaka.
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Lined up in a near straight line, these stars serve as a cosmic signpost.
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They can guide observers to brilliant Sirius and Canis Major, or to Aldebaran and Taurus.
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Each belt star is, in fact, a large, luminous star in its own right.
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Alnatak, for instance, is another hot, young, blue supergiant.
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At the heart of Orion's visual splendor lies a vast and complex region of dust and gas
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called the Orion Molecular Cloud Complex.
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This colossal structure is home to some of the sky's most photogenic nebula and active
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star-forming zones.
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Look just below Orion's belt.
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You'll spot Orion's sword, an asterism made of a few bright stars and the glowing Orion
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nebula, M42.
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Even to the unaided eye, under decent skies, this region can appear slightly fuzzy or cloudy
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hinting at the nebula's presence.
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In astrophotos, swirling clouds of magenta and violet hydrogen gas cradle young stars.
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Check it out in binoculars or a telescope.
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Even in light-polluted skies, you can see details.
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At its heart lies the trapezium cluster, a group of hot, massive stars whose intense
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ultraviolet radiation illuminates the nebula.
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The Orion nebula is one of the closest and most active star-forming regions to Earth,
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giving us a direct window into how stars and planetary systems are born.
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Just north of M42, and technically part of the same cloud, is M43, DeMarin's nebula,
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separated by a dark lane of dust.
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While it often gets overshadowed by its more famous neighbor, M43 is a wonderful emission
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region in its own right, another cradle for newly forming stars.
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The horsehead nebula is perhaps the most iconic dark nebula in the sky.
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The nebula, also known as Bernard 33, is a small, horse-shaped silhouette set against
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the bright emission nebula IC-434.
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Located near the leftmost belt star, Alnatak, this target typically requires a telescope
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with good filters or a long exposure photograph to really see the characteristic horsehead
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shape.
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Also near Alnatak is the flame nebula, NGC 2024, a region of hydrogen gas and dark dust
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lanes.
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The bright glow is largely due to ionization from a nearby young star.
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In images, it appears like a cosmic bonfire, living up to its evocative name.
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A bit farther north is M78, a reflection nebula.
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Unlike the emission nebula that glow with their own light, reflection nebula shine by
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reflecting the light of nearby stars.
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Through a modest telescope, M78 appears as a patchy, luminous cloud with a few embedded
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stars.
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Spanning much of Orion is a vast, faint arc called Bernard's Loop.
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It's believed to be a remnant of supernova explosions and powerful stellar winds from
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massive stars formed in Orion's past.
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In long exposure images, Bernard's Loop forms an elegant semi-circle framing many of the
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constellation's other features.
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Just north of the Orion Nebula lies the Running Man Nebula, NGC 1977, another region of mixed
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emission and reflection.
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Astrophotographers often note a dark shape in the gas that resembles a running figure,
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hence its name.
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Orion is a stellar nursery on a colossal scale.
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The Orion Molecular Cloud Complex houses massive clouds of hydrogen gas and interstellar
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dust.
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Under the force of gravity, these clouds can collapse, heating up and eventually igniting
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nuclear fusion to form new stars.
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This process is vividly on display in the Orion Nebula where astronomers have catalogued
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proplets, protoplanetary disks swirling around young stars.
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These disks may one day coalesce into fully formed solar systems, offering us a live-action
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look at the same processes that shaped our own sun and planets billions of years ago.
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Even if you have modest gear, Orion is an astrophotographer's paradise.
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You can effectively photograph the entire Molecular Cloud Complex with something as
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simple as an 85mm lens on a DSLR or mirrorless camera, using stacking techniques.
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You'll have better success with long, guided exposures.
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With such a setup, you can capture the glow of Orion's belt and sword and under dark conditions,
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you might even catch hints of Bernard's loop.
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A mid-level telephoto in the 135-200mm range can frame the belt stars, Horsehead Nebula,
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Flame Nebula, and Orion Nebula all in one shot.
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Through a small telescope, M42 is stunning.
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With filters like an H-alpha or UHC filter, the nebula's intricate structure becomes
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more apparent.
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Exposure stacking and various processing techniques are often used to preserve the
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bright core around the trapezium, while still capturing enough data to bring out faint outer
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details.
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If you're beginning your journey in astrophotography, M42 makes a captivating first target.
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I'm planning to talk more about some of these techniques in a future episode.
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For strictly visual observers, Orion is full of challenges and rewards.
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To the naked eye, under moderately dark skies, the Orion Nebula appears as a faint patch
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in the sword.
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A small telescope at low power reveals at least four bright stars in M42's heart, the
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trapezium.
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With excellent seeing conditions and a larger telescope, you can spot additional fainter
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members.
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Finding the flame nebula can be tricky.
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Try using a narrowband filter and keep the bright star on the tack just outside the field
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of view to reduce glare.
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For an additional challenge, try logging Betelgeuse's variability.
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Make note of its brightness changes over weeks or months.
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You'll want to compare it to other stars of known magnitudes to estimate its current
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brightness.
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Orion is sort of a universe in miniature and delivers one of the richest and most awe-inspiring
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experiences the sky has to offer.
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There's something here for everyone.
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It's one of the most studied and photographed areas of the entire sky, and for good reason.
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It's a grand cosmic stage where stars are born, live their brilliant lives, and eventually
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die in spectacular fashion.
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If you found this episode helpful, let me know and feel free to send in your questions
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and observations.
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The easiest way to do that is by visiting our website, startrails.show.
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This is also a great way to share the show with friends.
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Until next time, keep looking up and exploring the night sky.
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Clear skies, everyone.