Latest / Star Trails: From Backyard Astronomy to Cosmic Wonder / A Beginner’s Winter Sky Tour & the Wonders of Ceres

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A Beginner’s Winter Sky Tour & the Wonders of Ceres · Star Trails: From Backyard Astronomy to Cosmic Wonder

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Howdy Stargazers 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 5th through
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the 11th.
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It seems like it's been ages since we last met under the stars.
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We took a little break for the month of December to recharge, travel, and spend time with family
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and friends.
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I hope everyone had a great holiday break.
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If you may be found a new telescope under the tree or a pair of binoculars in your mantel
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stocking or just stumbled on the show out of a curiosity for astronomy, you're in luck
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because this episode is aimed at new backyard astronomers.
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In the first part of the episode, we're going on a guided tour through notable planets,
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constellations, and objects visible into night's sky.
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I'll share some tips for using telescopes and binoculars, and later in the show we'll
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cruise out to one of my favorite spots in the solar system, the enigmatic asteroid belt,
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home to the Dwarf Planet series.
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So grab a jacket if it's cold, find a comfortable spot under the night sky, and let's get started.
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Before we get oriented, be sure to go ahead and bring your scope or binoculars outside
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and let them acclimate to the temperature outdoors.
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Optics can expand and contract with temperature fluctuations, so letting them cool down to
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the ambient temperature will improve your visibility.
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Also, take a moment to let your eyes become used to the darkness.
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Try to avoid bright lights if you can, and don't ruin your night vision with your smartphone.
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Get it in dark mode and turn the screen brightness down.
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A red flashlight will also be useful.
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You won't need anything special for this observation, but in case you'd like a smartphone
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app to help you locate objects, go back and check out episode 37, where I shared my top
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picks for stargazing apps.
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I prefer the app Stellarium.
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One thing to keep in mind is that we'll occasionally refer to objects being a number
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of degrees above the horizon.
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An easy way to eyeball this measurement is by holding your fist at arm's length to the
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sky.
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Your fist will measure about 10 degrees from top to bottom.
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Be aware that some of the times and locations will vary depending on your latitude, so a
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smartphone app is going to come in handy.
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When we talk about finding objects in the night sky, it helps to have a reference point.
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For most of us in the Northern Hemisphere, that point is Polaris, the North Star.
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If you're just stepping outside, figure out which direction is North.
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It's easy to find West by facing the sunset, then make a quarter turn right to face North.
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A compass or a compass app can also help.
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Typically we'd use the Big Dipper or Ursa Major to help us locate Polaris.
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Currently, the Big Dipper is low on the horizon for North American observers just after dusk,
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but it will rotate into view later in the evening, becoming fully visible by midnight.
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When it's up, the two stars at the end of its bowl will point you directly to Polaris.
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You can also approximate the location of Polaris if you know your latitude.
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For example, if you're at a latitude of 34, as I am, Polaris will be about 34 degrees
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above the North horizon.
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When you see Polaris, you've found the sky's version of home base.
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It doesn't move through the night, so it's a good starting point.
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If you have a telescope with an equatorial mount, you'll often hear about polar alignment.
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This means aligning your mount so its axis points towards Polaris.
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While that's essential for astrophotography or tracking objects for long periods, don't
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let it intimidate you if you're just starting out.
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A rough alignment is often enough for casual observing.
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Check your scope's manual for the exact procedure, as all mounts are slightly different.
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So let's begin the tour.
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If you happen to be outside at twilight, just after sunset, look west and up at about a 30
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degree angle to spot the brightest star in the sky right now.
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That's actually the planet Venus.
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It's not much to look at in a telescope, but because it's between the Earth and Sun, it
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goes through phases like our moon.
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So you may see it in a crescent or gibbous phase, depending on the time of year.
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Its brightness is alluring, and I just enjoy looking at it with my naked eye.
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Just like the Sun, planets rise in the east and set in the west.
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Venus, having made its way across the sky during the day, will be setting around 8 p.m.,
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so catch it while you can.
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Now let's turn towards the east and about 40 degrees up, where we find Jupiter rising.
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It will be the brightest star in that area of the sky.
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Through a telescope, it kind of resembles a small solar system.
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You can see its four largest moons, Io, Europa, Ganymede, and Callisto, lined up around the
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planet.
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In a good telescope, you may even discern cloud bands on Jupiter's surface, or its
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raging storm, the great red spot.
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Now look back toward the west, gaze about a fist's width above and slightly to the
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left of Venus.
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You should be able to locate another relatively bright star here.
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That's Saturn, the ringed planet.
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Known for its gorgeous ring system, Saturn usually appears a bit fainter than Jupiter.
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If you can spot it, aim your telescope and prepare to have your breath taken away.
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Even at lower magnification, Saturn's rings are a jaw-dropping sight, and observing them
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never gets old.
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Some scopes may even resolve the gap in the rings, called the Cassini division.
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Looking south and higher in the sky, you can spot the moon around its first quarter this
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week, waxing towards next week's full moon.
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This is a great period for examining the moon's terminator.
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That's the dividing line between night and day on the lunar surface.
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In a telescope, you can see 3D-like relief where the light meets shadow.
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A fun fact, these dark patches you're seeing on the surface are maria, ancient lava planes.
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Imagine volcanic eruptions billions of years ago, shaping the face of our moon.
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The moon is an excellent first target for new telescope owners, and a great way to get
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acquainted with your instrument.
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When you're comfortable viewing the moon, move on to Jupiter and Saturn.
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Now let's check out some key constellations.
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Look south to southeast to spot one of the most recognizable constellations in the sky,
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Orion the Hunter.
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Orion is easily identified by his famous belt, three bright stars almost evenly spaced in
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a row.
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If you see those three stars, you found Orion.
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Above the belt, you'll notice a bright, ruddy star called Betelgeuse, a massive red supergiant
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nearing the end of its life.
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Below the belt, there's a bright blue-white star called Rigel, one of the most luminous
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stars we can see.
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Just below Orion's belt is a small, hazy patch.
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If you look at it with the naked eye, it appears like a fuzzy star.
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Aim your telescope or binoculars there, and you'll see the glowing gas and dust of the
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Orion nebula, one of the most spectacular deep sky objects you can see from your backyard.
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Even a modest telescope at low magnification reveals swirling gray-green or blueish clouds
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in the nebula.
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Just to the northwest of Orion, you'll find another majestic constellation, Taurus the
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Bull.
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The brightest star in Taurus is Aldebaran, a red giant that forms the fiery eye of the
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bull.
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You'll notice that Aldebaran is embedded in a loose cluster of stars known as the Hyades,
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this V-shaped cluster outlines the face of Taurus.
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A little higher in the sky and a bit to the right, if you're scanning from Orion, look
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for a tighter, dazzling cluster of stars known as the Pleiades.
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Also called the Seven Sisters, or M45, it's one of the easiest star clusters to spot with
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the naked eye.
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To many, it looks like a tiny version of the Big Dipper.
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Through binoculars or a wide-field telescope eyepiece, the Pleiades fills your view with
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luminous blueish-white stars.
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You might catch a hint of the reflection nebula around the brightest members, especially under
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dark skies.
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This cluster is young, only about a hundred million years old, practically newborns in
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cosmic terms.
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Back to the north and northeast, if you look high above Polaris, you'll see a distinct
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W-shape in the sky.
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That's Cassiopeia.
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It's an excellent landmark constellation that stands opposite the Big Dipper, helping frame
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Polaris between them.
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From Cassiopeia, you can star-hop toward the Andromeda Galaxy, M31, the nearest major
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galaxy to our own Milky Way.
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Star-hopping is a navigational technique in which you start from a bright, easily recognizable
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star and hop from one star to another using a chart or your memory.
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Think of it like following stepping stones across the sky.
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Each known star helps guide you closer to your target, whether it's a faint nebula or
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distant galaxy.
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I like to imagine the large triangle formed by Cassiopeia's top three stars as a giant
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arrow pointing the way to M31.
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Look about 15 degrees away from the arrow's pointer star to find M31.
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It's nearly directly overhead right now.
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M31 can be challenging to see with the naked eye.
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Under very dark skies, it can appear as a faint, fuzzy patch to the naked eye.
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But with binoculars or a small telescope, you'll see a brighter core surrounded by a
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delicate halo of light.
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If you've managed to locate the bright core of Andromeda in your telescope, you might
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even catch glimpses of its satellite galaxies, M32 and M110, depending on how dark your location
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is.
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Don't be disappointed if you can't see much detail.
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Galaxies are faint, extended objects, so it helps to let your eyes adapt to the dark
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and use averted vision.
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That's looking slightly away from the target to capture more detail.
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At 9 p.m., look back to the east to find another planet rising, Mars.
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Mars may appear as a bright, ruddy point of light.
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It doesn't show as many details as Jupiter or Saturn in a small telescope, but the color
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is unmistakable.
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Occasionally, you can make out bright polar caps or dark surface markings when Mars is
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closest to the Earth.
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No matter which of these objects you decide to explore first, here are some tips to make
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your stargazing experience more enjoyable.
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Use lower magnification first.
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Start with your telescope's lowest power eyepiece.
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This gives you a wider field of view, making it easier to find and center objects.
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Once you've acquired your target, you can swap to higher magnifications.
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Stabilize your scope.
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Telescopes can be wobbly, especially cheaper models, and even the slightest touch can knock
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an object out of your field of view, particularly at high magnifications.
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Make sure your telescope is on level ground and your mount is properly adjusted and locked
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down.
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Even a slight wobble can make focusing difficult.
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If you have a Dobsonian mount, try placing it on a perfectly flat surface.
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Be careful of bumping the scope when you look through the eyepiece.
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Unless you have a computerized scope that finds targets automatically, you're going
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to spend a good bit of time simply placing your target in the field of view.
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Your first night with a new scope is probably going to be frustrating, but once you get
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the hang of it, you'll be sliding around the sky with ease.
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Aligning your finder scope, or red dot finder, in daylight on a distant tree or telephone
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pole is a huge time saver.
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This helps you accurately aim at celestial targets when the sky is dark.
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Keep a little notebook or use a voice recorder to jot down your observations, sketches, or
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anything interesting you notice.
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Over time, this will help you track your progress and build your skills as an observer.
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Saturn, Jupiter, and the Moon are all very dynamic targets that change from night to
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night, so it pays to revisit them often.
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If you live in an urban or suburban area, you might struggle with light pollution.
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Street lights, car headlights, and the glow from nearby buildings can wash out fainter
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stars and deep sky objects.
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If you can, plan a trip to a darker location, maybe a local park or campsite away from
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city lights.
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You'll be amazed at how many more stars you can see.
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And one last note, be patient.
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And I say this as someone who is very impatient.
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Telescopes, especially for beginners, require a bit of practice before that wow moment.
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The more you use it, the better you'll get at finding objects quickly, focusing and picking
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out faint details.
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Journey is a lifetime hobby, and the night sky offers endless discoveries.
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If you can't find what you want to see tonight, there's always tomorrow.
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As the year progresses, I'll make note of night sky objects to keep an eye out for.
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You may even want to go back and check out some of the episodes in the back catalog.
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The winter is one of the best times for stargazing, owing to longer nights and clearer skies.
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So if you've just started your journey, you're coming in at a very good time.
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Today we're focusing on a fascinating region of the solar system, the asteroid belt.
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This expanse of rocky bodies has captivated astronomers for centuries, and in it lies
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the dwarf planet Ceres, a world that's rewriting what we know about these ancient remnants
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of planetary formation.
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The asteroid belt is a vast region of space located between the orbits of Mars and Jupiter.
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Unlike the chaotic obstacle courses often depicted in movies, such as the asteroid sequence
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in Empire Strikes Back, the asteroid belt itself is mostly empty.
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Although it contains millions of objects, these are spread out across a region spanning
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more than 140 million miles.
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The combined mass of the entire belt is only about 3% of our moon's mass.
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This region is home to objects of all shapes and sizes, from dust grains to large bodies
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like Ceres, which alone accounts for 40% of the belt's total mass.
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These objects date back to the early days of the solar system.
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They're often described as failed planets or leftovers that couldn't form a larger
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body owing to the disruptive gravitational influence of Jupiter, whose immense gravity
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is responsible for shaping the asteroid belt.
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Jupiter's influence has created gaps in the belt known as Kirkwood gaps, areas cleared
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of asteroids by orbital resonances with the gas giant.
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This dynamic prevents the asteroid belt from becoming a static graveyard of rocks.
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It's a constantly evolving part of the solar system.
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Ceres is the largest object in the asteroid belt.
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It was discovered in 1801 by Giuseppe Piazzi, who originally classified it as a planet.
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As more objects were found in the belt, Ceres was reclassified as an asteroid.
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In 2006, it was promoted to dwarf planet status, alongside Pluto.
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Interestingly, Ceres was considered a planet for a little more than 50 years.
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Pluto had that distinction for a little while longer, at 76 years.
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Ceres is about 590 miles in diameter, roughly the size of Texas, and it's made up of rock
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and water ice.
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Its density suggests it has a layered structure, a rocky core surrounded by a mantle rich in
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water.
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In fact, Ceres is thought to contain more water than all of Earth's fresh water combined.
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Most of it likely locked beneath its surface as ice or even liquid in a subsurface ocean.
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One of the most striking features is Ahuna Mons, a cryovolcano that towers about 4 kilometers
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high.
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Like the lava spewing volcanoes on Earth, Ahuna Mons erupts icy slush.
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This indicates that Ceres has been geologically active in the recent past, possibly within
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the last few hundred million years.
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In 2015, NASA's Dawn spacecraft became the first mission to orbit a dwarf planet.
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After visiting the asteroid Vesta, Dawn arrived at Ceres and began sending back data that transformed
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our understanding of this small world.
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One of its most surprising discoveries were the bright spots in the Akator crater.
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These spots, visible even from a distance, turned out to be deposits of sodium carbonate,
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a type of salt.
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Scientists believe these salts were left behind when briny water from Ceres's interior
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seeped to the surface and sublimated, leaving the salt behind.
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These discoveries suggest that Ceres has or had a subsurface reservoir of liquid water.
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The mission also found evidence of organic molecules.
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Combined with the presence of water, this raises the tantalizing possibility that Ceres
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might once have supported prebiotic chemistry, the early steps toward life.
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While there's no evidence of life itself, these findings make Ceres a compelling target
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for future astrobiological studies.
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Ceres formed about four and a half billion years ago, around the same time as the rest
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of the solar system.
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So by studying it, scientists can learn more about the conditions that existed during those
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early turbulent days when planets were forming.
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Ceres also offers practical opportunities for the future of space exploration.
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Its water ice could be harvested to provide drinking water for astronauts or converted
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into hydrogen and oxygen for rocket fuel.
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If humanity ever ventures into the outer solar system, places like Ceres could become vital
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refueling stations.
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Finally, Ceres challenges us to rethink our assumptions about what an asteroid world looks
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like.
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Its geology, chemistry, and even its thin atmosphere all point to a body that has been
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far more active and dynamic than we once imagined.
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It isn't simply a rock floating in space.
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So, you might be wondering, can you see Ceres from your backyard?
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The answer is yes, with a keen eye and some planning.
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Ceres is visible in a good pair of binoculars or a small telescope when it's at opposition,
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the point when it's closest to Earth in its orbit.
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This year, Ceres reaches opposition in October when it's estimated to be around a magnitude
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of 7.6.
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A stargazing app can help you locate it as it slowly moves through the constellations.
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While it won't look like more than just a faint dot, knowing you're observing the
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largest object in the asteroid belt and the dwarf planet closest to Earth is an awe-inspiring
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experience.
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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 your friends.
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Until next time, keep looking up and exploring the night sky.
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Clear skies, everyone!