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StarDate Online - Your guide to the universe





 



New Moon

Fri, 23 Jun 2017 05:00:00 +0000

The Moon is “new” today, as it crosses the imaginary line between Earth and Sun. It will return to view as a thin crescent on Sunday evening, quite low in the west shortly after sunset.




Storm Damage

Fri, 23 Jun 2017 05:00:00 +0000

Solar storms can create all sorts of trouble. They can knock out power grids, cripple orbiting satellites, and disrupt airline schedules and radio communications. And a team of scientists is looking at one other possible form of trouble: stranding events for whales, dolphins, and porpoises.

These marine mammals, known as cetaceans, have internal compasses to help them navigate the world’s oceans. But solar storms are caused by short-circuits in the Sun’s own magnetic field. They can send massive clouds of charged particles toward Earth. These particles cause problems when they hit Earth’s magnetic field.

The researchers suggest that one of those problems is interfering with the navigation of cetaceans.

These animals sometimes strand themselves on the beach, either individually or in groups. There are many possible causes for the strandings, including diseases and storms. And sonar causes some strandings by interfering with the animals’ internal sonar, which they use to locate both prey and others of their own kind.

Because the animals have an internal compass to sense Earth’s magnetic field, though, the researchers suggest that solar storms could be another cause of strandings. The team will comb through many years of observations of strandings and solar storms. They’ll compare the two to see if there’s a relationship — perhaps identifying another threat to these beautiful creatures.

Tomorrow: three stars for the price of one.

 

Script by Damond Benningfield

StarDate: 
Friday, June 23, 2017
Teaser: 
Risks from storms on the Sun



Eltanin

Thu, 22 Jun 2017 05:00:00 +0000

Eltanin, an Arabic name that means “the serpent,” is the brightest star of Draco, the dragon, which is high in the north on summer evenings. Eltanin is as bright as the nearby North Star, Polaris.




Quiet Sun

Thu, 22 Jun 2017 05:00:00 +0000

The Sun has been unusually “quiet” in recent years — the quietest in more than a century. And forecasters say there’s a good chance it’ll be even quieter over the next few decades.

The Sun’s level of activity is determined by its magnetic cycle. On average, a cycle lasts about 11 years. The Sun is most active at the cycle’s peak, when it can be covered by dozens of sunspots and produce big outbursts of energy and charged particles. These outbursts can knock out power grids on Earth, damage orbiting satellites, and disrupt our technology in many other ways.

Astronomers have been watching the solar cycles for four centuries. And they’ve been counting them since 1755. Right now, we’re near the end of Cycle 24.

The most active solar cycle ever recorded peaked in the early 1960s. The cycles since then have been weaker. And the current one is the weakest since the early 1900s. Over the last few years, in fact, there have been dozens of days when there were no sunspots at all.

And scientists say that trend could continue. Early forecasts call for Cycle 25 to be even weaker than the current one, with Cycle 26 weaker still. In fact, we could be heading into a period of weakness that could rival the Maunder Minimum — a period in the 17th and 18th centuries where the Sun was almost comatose. If so, then the Sun could remain quiet through the end of the century — giving our technology a break from our star’s disruptive effects.

 

Script by Damond Benningfield

StarDate: 
Thursday, June 22, 2017
Teaser: 
A long period of rest for the Sun



Hot Halo

Wed, 21 Jun 2017 05:00:00 +0000

Clouds of charged particles form a halo around the Perseus galaxy cluster in this combined radio and optical view. The radio view, in red, is produced by particles that are accelerated by collisions between galaxies or by powerful jets from supermassive black holes. The halo spans about 1.3 million light-years. [Gendron-Marsolais et al.; NRAO/AUI/NSF; NASA; SDSS]

(image)



Odd Ophiuchus

Wed, 21 Jun 2017 05:00:00 +0000

Ophiuchus, the serpent bearer, passes high across the south tonight, above Sagittarius and Scorpius. Ophiuchus is the only one of the 13 constellations along the Sun’s path that is not a member of the zodiac.




Busy Sun

Wed, 21 Jun 2017 05:00:00 +0000

The Sun is one of the steadiest of all stars. Even so, its energy output does vary — by less than a tenth of one percent. This variation takes place over an 11-year cycle that’s tied to changes in the Sun’s magnetic field. But cycles aren’t the same. The most intense yet seen peaked in the early 1960s. And right now, we’re in the middle of the weakest cycle in more than a century.

The Sun is a big, spinning ball. Because it’s made of gas, different layers and different latitudes rotate at different rates. That causes the Sun’s magnetic field to get twisted and tangled. Lines of magnetic force poke through the surface, creating dark sunspots, giant eruptions, and other activity. When the cycle peaks, the Sun can be covered with dozens of sunspots.

Astronomers have been tracking sunspots for more than 400 years. In the late 1600s and early 1700s, they saw almost no sunspots at all — a period known as the Maunder Minimum. It corresponded to a period of unusually cold weather in North America and Europe. Four of the five busiest cycles they’ve seen have happened in the last 75 years or so.

By looking at tree rings, and at ice cores from Antarctica and Greenland, scientists have estimated the intensity of solar cycles going back more than 11,000 years. And they’ve found that the peaks of the mid-20th century are the strongest in at least 8,000 years.

Over the last few cycles, though, that intensity has faded. More about that tomorrow.

 

Script by Damond Benningfield

StarDate: 
Wednesday, June 21, 2017
Teaser: 
Some busy years for the Sun



Summer Solstice

Tue, 20 Jun 2017 05:00:00 +0000

Summer begins tonight in the northern hemisphere, when the Sun stands farthest north for the year — a moment known as the summer solstice. The season lasts until the September equinox, when the Sun crosses the equator from north to south.




Summer Solstice

Tue, 20 Jun 2017 05:00:00 +0000

The modern calendar is one of the oldest and most basic astronomical instruments. It measures the relative motions of Earth and the Sun. A day, for example, is the average length of time it takes the Sun to return to the same place in the sky: 24 hours. And a year is the time it takes Earth to make one complete turn around the Sun.

So perhaps it’s not surprising that the calendar uses astronomical definitions for the seasons: key points in the Sun’s annual migration across the sky.

Summer, for example, begins tonight here in the northern hemisphere, when the Sun stands farthest north for the year — a moment known as the summer solstice. And the season lasts until the September equinox, when the Sun crosses the equator from north to south. The solstice also marks the longest day of the year.

For centuries, the calendar was timed to match the seasons as well. In Great Britain and its American colonies, for example, the year began at the spring equinox in March. It wasn’t until 1752 that the British calendar was changed to move the start of the year to January 1st.

Of course, astronomy isn’t the only way to mark the seasons. Meteorologists, for example, have a slightly different range for summer: from the first of June through the end of August. And families follow the school calendar, in which summer also spans June through August — different ways to mark the cycles of the Sun.

We’ll have more about the Sun tomorrow.

 

Script by Damond Benningfield

StarDate: 
Tuesday, June 20, 2017
Teaser: 
Marking time by the motions of the Sun



Moon and Venus

Mon, 19 Jun 2017 05:00:00 +0000

Venus, the brilliant “morning star,” will stand to the left of the Moon at first light tomorrow, and about the same distance to the upper right of the Moon on Wednesday.




Moon and Venus

Mon, 19 Jun 2017 05:00:00 +0000

One of the loveliest events in the night sky is a close alignment of the Moon and the planet Venus. And just such an alignment takes place the next couple of days before and during dawn. Venus, the brilliant “morning star,” stands to the left of the Moon at first light tomorrow, and about the same distance to the upper right of the Moon on Wednesday.

A close alignment between two or more astronomical objects is called a conjunction. The Moon has several of them every month, because it makes a full loop against the background of stars and planets.

And it’s always the same roster of companions, because the Moon follows a narrow path across the sky. In fact, it stays close to the Sun’s path, known as the ecliptic. Several bright stars lie near the ecliptic, and so do the bright planets. So the Moon swings past each of these objects every month, staging beautiful conjunctions.

The Moon also has conjunctions with the Sun. Most months, these conjunctions are invisible. The Moon’s path is tilted just a bit with respect to the ecliptic, so the Moon usually swings just above or below the Sun, where it’s lost in the glare.

In August, though, the Moon will be crossing the ecliptic just as it passes the Sun. That will create the most beautiful of all astronomical encounters: a total solar eclipse. Its path will cross the United States from Oregon to South Carolina — a beautiful conjunction between the Moon and Sun.

More about the Sun tomorrow.

 

Script by Damond Benningfield

StarDate: 
Monday, June 19, 2017
Teaser: 
Beautiful encounters with the Moon



A Civil Sky

Sun, 18 Jun 2017 05:00:00 +0000

Evening twilight descends on McDonald Observatory and the Davis Mountains of West Texas. This depicts civil twilight, when the Sun is no more than six degrees below the horizon, and the sky is still fairly bright. Full astronomical twilight, when the Sun is between 12 and 18 degrees below the horizon, will come later, providing skies that are dark enough to allow astronomers to begin staring into the depths of the universe. [Damond Benningfield]

(image)



Approaching Summer

Sun, 18 Jun 2017 05:00:00 +0000

Summer arrives on Tuesday night, with the summer solstice. Tuesday and Wednesday will be the longest days of the year here in the United States — the greatest intervals between sunrise and sunset.




Twilight

Sun, 18 Jun 2017 05:00:00 +0000

A Civil Sky Evening twilight descends on McDonald Observatory and the Davis Mountains of West Texas. This depicts civil twilight, when the Sun is no more than six degrees below the horizon, and the sky is still fairly bright. Full astronomical twilight, when the Sun is between 12 and 18 degrees below the horizon, will come later, providing skies that are dark enough to allow astronomers to begin staring into the depths of the universe. [Damond Benningfield] Summer arrives on Tuesday night, with the summer solstice. Tuesday and Wednesday will be the longest days of the year here in the United States — the greatest intervals between sunrise and sunset. But the light of day doesn’t begin or end at those moments. Sunlight filters into the sky long before the Sun breaks the horizon in the morning, and long after it disappears in the evening. These periods are known as twilight. But there are several versions of twilight, all of which depend on how far below the horizon the Sun is. What most of us think of as twilight is known as civil twilight. In the evening, it begins at sunset and ends when the Sun has dropped six degrees below the horizon — about the width of three fingers held at arm’s length. There’s still light in the sky at the end of civil twilight, but not enough for everyday activities, such as driving. When the Sun is between six and 12 degrees below the horizon, it’s nautical twilight. When sailors navigated by the stars, they could begin to see stars during this period, but they could also still see the horizon, so it was a good time to take readings. Finally, when the Sun is between 12 and 18 degrees below the horizon, it’s astronomical twilight. It’s dark enough for astronomers to observe brighter stars and planets, but not dark enough to see faint galaxies and nebulae. When astronomical twilight ends, the sky’s just about as dark as it’s going to get — the darkness of another night.   Script by Damond Benningfield Keywords: SeasonsWeather and Atmospheric PhenomenaStarDate: Sunday, June 18, 2017Teaser: Dark, darker, and darkest skies [...]



Sunrise and Sunset

Sat, 17 Jun 2017 05:00:00 +0000

The timekeeper for the United States, the Naval Observatory, defines sunrise and sunset as the moments when the center of the Sun is physically 50 minutes of arc below the horizon, which is less than the width of your finger held at arm’s length.




Sunrise and Sunset

Sat, 17 Jun 2017 05:00:00 +0000

In the modern world, there’s a rule, a regulation, or a definition for just about everything. And that includes such everyday events as sunrise and sunset.

There are several ways to think of these daily bookends. They can be the points at which the Sun is bisected by the horizon — half in view, half not. Or they can be the points when the Sun has dropped below the horizon. Or, in the modern definition, they can be the points when the Sun drops from view.

You might think those last two would be the same, but they’re not. Earth’s atmosphere acts as a lens, bending the Sun’s rays. So when you see the Sun standing just atop the horizon, it’s actually below the horizon, but the atmosphere has projected an image of the Sun into view.

So the official timekeeper for the United States, the Naval Observatory, defines sunrise and sunset as the moments when the center of the Sun is physically 50 minutes of arc below the horizon — a bit less than one degree. That accounts for the size of the Sun itself, and the “bending” properties of the atmosphere.

The atmosphere can bend the Sun’s rays at different angles at different times, though. So the predicted times of sunrise and sunset can be off by a minute or so. And when the Sun rises and sets at a low angle to the horizon, they can be off by several minutes.

And even when the Sun does drop from sight, the atmosphere scatters its light back into view, producing twilight. More about that tomorrow.

 

Script by Damond Benningfield

StarDate: 
Saturday, June 17, 2017
Teaser: 
Defining the day’s “bookends”



Big Changes

Fri, 16 Jun 2017 05:00:00 +0000

Hydra, the water snake, slithers quite low across the southwest at nightfall. One of its treasures is the binary system V Hydra. Its main star is old and puffed up. It expels gas into space, which the second star grabs, then shoots out like cannonballs.




Big Changes

Fri, 16 Jun 2017 05:00:00 +0000

For most of a star’s long life, things happen slowly. A star like the Sun, for example, steadily converts hydrogen to helium in its core for about 10 billion years. At the end of that run, the pace picks up. And in the star’s final, colorful act, major changes can happen over just a few centuries.

One star that may be going through that last act is in Hydra, the water snake, which slithers quite low across the southwest at nightfall.

V Hydra appears to consist of two stars. The main star is the same mass as the Sun. It’s at the very end of its life, though, so it’s puffed up to more than 400 times the Sun’s diameter. The star pulses in and out like a beating heart, and it’s ejecting a lot of gas into space.

The second star orbits the bigger one every eight and a half years on a stretched-out path. When it gets close to the bigger star, it grabs some of the expelled gas, forming a disk. When enough gas builds up, some of it may be flung back into space as a “cannonball” — a blob that’s twice as heavy as the planet Mars.

So today, astronomers are seeing big changes in V Hydra every few years. And the changes could come even faster in the not-too-distant future. The bigger star may soon expel all of its outer layers of gas into space, forming a colorful nebula. The companion may sculpt it into an exotic shape — perhaps an hourglass, or even a butterfly. It’s a process that could play out very soon — a fast-paced change for a Sun-like star.

 

Script by Damond Benningfield

StarDate: 
Friday, June 16, 2017
Teaser: 
A Sun-like star picks up the pace



Blowing Bubbles

Thu, 15 Jun 2017 05:00:00 +0000

A multi-wavelength image shows the Ring Nebula, the last gasp of a dying star. As the nuclear reactions in its core began to slow down, it started blowing strong winds into space, which form the dark red rings and arcs, shown in infrared light. Later, the star began expelling its outer layers in bulk, forming the brighter doughnut-shaped structure at center. Different colors show different chemical elements: red is hydrogen, for example, while blue is oxygen. The expanding nebula probably is shaped like a barrel, and we're looking through its open end. In a few thousand years, the nebula will dissipate, leaving only the star's hot but dead core, known as a white dwarf. [NASA/ESA/C.R. Robert O’Dell (Vanderbilt)/G.J. Ferland (Kentucky)/W.J. Henney and M. Peimbert (UNAM)]

(image)



Planetary Nebulae

Thu, 15 Jun 2017 05:00:00 +0000

The last gasp of a dying star climbs the eastern sky on June evenings. The Ring Nebula is not far to the lower right of the brightt star Vega, which is about halfway up the sky as night falls. The nebula consists of the ejected outer layers of a once-normal star.




Planetary Nebulae

Thu, 15 Jun 2017 05:00:00 +0000

Blowing Bubbles A multi-wavelength image shows the Ring Nebula, the last gasp of a dying star. As the nuclear reactions in its core began to slow down, it started blowing strong winds into space, which form the dark red rings and arcs, shown in infrared light. Later, the star began expelling its outer layers in bulk, forming the brighter doughnut-shaped structure at center. Different colors show different chemical elements: red is hydrogen, for example, while blue is oxygen. The expanding nebula probably is shaped like a barrel, and we're looking through its open end. In a few thousand years, the nebula will dissipate, leaving only the star's hot but dead core, known as a white dwarf. [NASA/ESA/C.R. Robert O’Dell (Vanderbilt)/G.J. Ferland (Kentucky)/W.J. Henney and M. Peimbert (UNAM)] When a Sun-like star dies, it leaves a brilliant corpse — a glowing shell of gas that can look like a ring, a box, or even an hourglass. The colorful object doesn’t last forever, though — it slowly fades from sight. Such a beautiful corpse is known as a planetary nebula — not because it has anything to do with planets, but because it can look like a planet when seen through a telescope. And one of the brightest and best known is in good view at this time of year. The Ring Nebula is not far to the lower right of the brilliant star Vega, which is about halfway up the eastern sky at nightfall. Long-exposure images show an oval that’s bright red and yellow on the outside, and pale blue and green in the center. The nebula began forming several thousand years ago, as its star stopped producing nuclear reactions in its core. The core began to shrink and get much hotter. A couple of thousand years ago as seen from Earth, radiation from the core began pushing away the star’s outer layers. As they expanded into space, energy from the superhot core caused them to glow — forming the Ring Nebula. The nebula is probably shaped like a barrel or a thick doughnut, and we’re looking straight through the hole in the middle. Other planetary nebulae may have companion stars that sculpt them into more exotic shapes, from hourglasses to butterflies — creating beautiful final acts among the stars. We’ll talk about the possible birth of a planetary nebula tomorrow.   Script by Damond Benningfield   Keywords: Planetary NebulaeRing Nebula, M57StarDate: Thursday, June 15, 2017Teaser: A star’s colorful demise [...]



Argonauts

Wed, 14 Jun 2017 05:00:00 +0000

Hercules and Ophiuchus are in the east this evening. Hercules is named for the Greek hero, while Ophiuchus, the serpent-bearer, is named for the mythological founder of Greek medicine. Both joined Jason aboard the Argo in search of the golden fleece.




Saturn at Opposition III

Wed, 14 Jun 2017 05:00:00 +0000

The surface of the largest moon of Saturn looks a lot like Earth, with mountains, riverbeds, lakes, and dunes. But while the dunes on Titan look like those on Earth, they’re really quite different. Their particles of “sand” may form in a different way, and the dunes align in the opposite direction from the prevailing winds.

Titan looks so Earth-like because it has a cold, thick atmosphere. Winds, along with rains of liquid methane and ethane, sculpt the surface — including the dunes. In fact, the grains that make up the dunes may consist of particles of organic compounds that stick together in Titan’s atmosphere and fall to the surface like sleet.

The dunes are found along Titan’s equator. They’re up to 30 stories high and hundreds of miles long.

Most of them point to the east. But climate models suggest that Titan’s prevailing winds are from the west, so the dunes ought to aim in that direction.

A recent study says they may align against the wind because the grains that make up the dunes have an electric charge, so they clump together. Titan’s everyday winds are too weak to move the clumps. At the equinoxes, though, jet streams that move eastward may give birth to big storms. Winds from those storms could be strong enough to sculpt the dunes on this intriguing moon.

Look for Saturn low in the southeast and south this evening. It looks like a bright golden star. Titan is visible through good binoculars or a telescope.

 

Script by Damond Benningfield

 

 

StarDate: 
Wednesday, June 14, 2017
Teaser: 
Sculpting sand dunes on a cold world



Altair

Tue, 13 Jun 2017 05:00:00 +0000

Altair, one of the closest and brightest stars in the night sky, is in good view on June evenings. It forms the southern point of the Summer Triangle, which is low in the east and northeast at nightfall, and wheels high across the sky during the night.




Saturn at Opposition II

Tue, 13 Jun 2017 05:00:00 +0000

Lightning can make an AM radio station crackle. It can also produce radio static on other planets. In fact, the Cassini spacecraft recorded this “crackling” from storms on Saturn, the second largest planet in the solar system.

Lightning on Saturn can be up to 10,000 times stronger than the typical flash here on Earth. But it’s also much less common: thousands of flashes per year, compared to millions on Earth.

Lightning on Saturn forms in the same way as lightning on Earth: in big thunderstorms. Warm water vapor rises high into the atmosphere, creating static electricity. When that static discharges, it produces lightning.

Most of the lightning on Saturn has been concentrated in one region of the southern hemisphere, and a single monster storm in the northern hemisphere. The southern region is known as “storm alley.” One storm in that region lasted for nine months, although it didn’t produce lightning all the time.

The northern storm eventually wrapped around the entire planet. It produced the highest rate of lightning flashes yet recorded — about 10 per second: the most brilliant display yet seen on the giant planet.

We can’t see the lightning from here on Earth, but we can see Saturn. It’s in the southeast at nightfall, and looks like a bright golden star. It arcs across the southern sky during the night, and sets around sunrise. More about Saturn tomorrow.

 

Script by Damond Benningfield

 

StarDate: 
Tuesday, June 13, 2017
Teaser: 
Lighting up the skies on another planet



Making Waves

Mon, 12 Jun 2017 05:00:00 +0000

The moon Daphnis, which is about five miles (8 km) long, creates ripples in Saturn's rings as it orbits the giant planet in this January image from the Cassini spacecraft. The gravitational pull of Daphnis and other small moons stirs up the rings, which are quite dynamic. Collisions with ring material can shatter the small moons, but more material can coalesce to form new moons. Ring material rams into the surfaces of some of Saturn's larger moons, blasting out rock and ice which can then join the rings. Geysers on the moon Enceladus also supply an outer ring with fresh ice. [NASA/JPL/SSI]

(image)



Saturn at Opposition

Mon, 12 Jun 2017 05:00:00 +0000

The planet Saturn is putting on its best showing of the year this week. It’s low in the southeast as night falls and looks like a bright gold star. It arcs across the south later on, and remains in view all night.




Saturn at Opposition

Mon, 12 Jun 2017 05:00:00 +0000

Making Waves The moon Daphnis, which is about five miles (8 km) long, creates ripples in Saturn's rings as it orbits the giant planet in this January image from the Cassini spacecraft. The gravitational pull of Daphnis and other small moons stirs up the rings, which are quite dynamic. Collisions with ring material can shatter the small moons, but more material can coalesce to form new moons. Ring material rams into the surfaces of some of Saturn's larger moons, blasting out rock and ice which can then join the rings. Geysers on the moon Enceladus also supply an outer ring with fresh ice. [NASA/JPL/SSI] It’s rare for second place to outshine first. Most of the accolades go to the winner of the NBA Finals or the gold medalist at the Olympics, not the runner-up. Yet among the planets of the solar system, second place is a lot more memorable than first. That’s because the second-largest planet is Saturn, the most easily identifiable world other than our own. Its bright rings are both beautiful and memorable — the most distinctive feature of any planet or moon. The rings are made of small bits of ice mixed with chunks of rock and a sprinkling of dust. Scientists aren’t positive just when they formed — whether it was billions of years ago, or much more recently. But scientists are sure that the rings are dynamic. As small moons orbit within the rings, for example, their gravity pushes the ring material, creating ripples that look like the wake of a passing boat. Small moons are sometimes pulverized by collisions, adding material to the rings. At the same time, ring particles can bunch up to form new moons. And one of the outer rings gets fresh ice from geysers on one of Saturn’s bigger moons. That helps make Saturn’s rings intriguing as well as beautiful — enhancing the appeal of the solar system’s runner-up. And Saturn is putting on its best showing of the year this week. It’s low in the southeast as night falls, and looks like a bright gold star. It arcs across the south later on, and remains in view all night. More about Saturn tomorrow.   Script by Damond Benningfield   Keywords: SaturnSaturn's RingsStarDate: Monday, June 12, 2017Teaser: A runner-up to no planet [...]



Messier 5

Sun, 11 Jun 2017 05:00:00 +0000

The star cluster Messier 5 stands high in the southeast at nightfall, far to the lower left of Arcturus, a bright yellow-orange star. Through binoculars, M5 looks like a fuzzy star. Small telescopes reveal some of its individual stars.




Messier 5

Sun, 11 Jun 2017 05:00:00 +0000

Our home galaxy, the Milky Way, is about 13 billion years old. We know the age because some of its original stars are still around. Many of them congregate in giant ball-shaped clusters. And one of those clusters is in good view at this time of year. Messier 5 is in the constellation Serpens, the serpent. As night falls, it’s well to the lower left of Arcturus, a bright yellow-orange star that’s high in the south. Through binoculars, the cluster looks like a fuzzy star. Small telescopes begin to reveal some of its individual stars. In all, M5 has at least a hundred thousand stars, and perhaps as many as half a million. Most of them are packed into a spherical region that’s about 165 light-years across. For that reason, M5 is known as a globular cluster. The cluster is about 13 billion years old. Astronomers determined that age by taking a census of its stars. More-massive stars burn out faster than less-massive ones. So finding the heaviest remaining stars in a cluster reveals its age. In this case, the oldest remaining stars are a bit less massive than the Sun, so they’re a bit fainter and oranger. M5 orbits the center of the galaxy at more than a million miles per hour. That suggests that it comes from the galaxy’s halo — a spherical region that extends far outside the Milky Way’s bright disk. Right now, M5’s orbit has brought it near the disk. Over time, though, it will again loop into the outer reaches of the halo, leaving the disk behind.   Script by Damond Benningfield   Keywords: Messier ObjectsStar ClustersStarsStarDate: Sunday, June 11, 2017Teaser: Some of the oldest stars in the galaxy[...]