Subscribe: StarDate
http://stardate.org/feeds/rss.xml
Added By: Feedage Forager Feedage Grade B rated
Language: English
Tags:
asteroid  atmosphere  bright  earth  galaxy  it’s  moon  october teaser  october  planet  space  star  stars  uranus   
Rate this Feed
Rate this feedRate this feedRate this feedRate this feedRate this feed
Rate this feed 1 starRate this feed 2 starRate this feed 3 starRate this feed 4 starRate this feed 5 star

Comments (0)

Feed Details and Statistics Feed Statistics
Preview: StarDate

StarDate Online - Your guide to the universe





 



Distant Rings

Thu, 19 Oct 2017 05:00:00 +0000

Small moons orbit within the faint rings of the planet Uranus, as shown in this diagram. The rings form several narrow bands, shown in white, and a few wider bands, in blue and orange. Some of the moons acts as shepherds, keeping the ring material in place. Most of the rings particles are tiny, but some are as big as pickup trucks. [Ruslik0/Wikimedia]

(image)



More Uranus at Opposition

Thu, 19 Oct 2017 05:00:00 +0000

Distant Rings Small moons orbit within the faint rings of the planet Uranus, as shown in this diagram. The rings form several narrow bands, shown in white, and a few wider bands, in blue and orange. Some of the moons acts as shepherds, keeping the ring material in place. Most of the rings particles are tiny, but some are as big as pickup trucks. [Ruslik0/Wikimedia] Like peanut butter, planetary rings come in different textures. The rings of Jupiter and Neptune are smooth because the ring particles are tiny. But the rings of Saturn and Uranus are more chunky. They contain plenty of small particles, but they have big chunks mixed in. These different textures can reveal how the rings were made. The particles in the rings of Jupiter and Neptune probably flake off the moons of these planets when the moons are hit by big space rocks. The bits of debris then spread out to form rings. The small particles in the rings of Uranus probably form in the same way. But the rings of Uranus also contain chunks as big as pickup trucks. These pieces may be debris from a moon that was pulverized by a collision with a comet or asteroid. The rings of Uranus are darker than charcoal, so they were discovered just 40 years ago. Even then, they were found only because they blocked the light of a star that was passing behind them. There are several tight bands of material within the rings. These bands are no more than a few miles wide. They probably are “penned in” by small moons, which act like shepherds — their gravity keeps their flocks of ring materials from drifting away. And Uranus is putting in its best appearance of the year. It rises at sunset, in the constellation Pisces, and remains in view all night. It’s also closest to us for the year, so it shines brightest. Even so, you need binoculars to find it.   Script by Damond Benningfield Keywords: Planetary RingsUranusStarDate: Thursday, October 19, 2017Teaser: Smooth or chunky? [...]



New Moon

Thu, 19 Oct 2017 05:00:00 +0000

The new Moon will accompany the Sun as it climbs across the sky today. We can’t see the Moon because it is immersed in the Sun’s glare. The exact moment of new Moon is 2:12 p.m. CDT. The Moon will return to view after sunset tomorrow or Saturday.




Uranus at Opposition

Wed, 18 Oct 2017 05:00:00 +0000

The planet Uranus is putting in its best appearance of the year this week. It rises at sunset and remains in the sky all night. It’s also closest to us for the year, at less than 1.8 billion miles, so it shines brightest. In fact, under especially dark skies, for those with very good vision, it’s barely visible to the unaided eye. Most of us, though, need binoculars to find it.

Uranus is one of the giants of the solar system — only Jupiter and Saturn are bigger. But Uranus may be put together differently from its larger siblings.

Jupiter and Saturn are balls of hydrogen and helium wrapped around solid cores. Uranus probably has a solid core, too, but it has a lot less hydrogen and helium.

All of those elements that it does have are contained in an atmosphere that’s perhaps 3,000 miles thick — about one-fifth of the distance down from the tops of the planet’s clouds.

Below that may be a liquid or partially frozen mixture of water, methane, and rocky minerals. Unlike the boundary between the oceans and air here on Earth, though, there probably isn’t a sharp boundary between the layers of Uranus. The pressure is so great that the liquid and gas merge in a slushy transition zone.

Uranus climbs into view in the southeast an hour or two after sunset, near the eastern edge of the constellation Pisces. Through binoculars, it looks like a faint blue-green star — a giant world far from the Sun.

We’ll have more about Uranus tomorrow.

 

Script by Damond Benningfield

Keywords:

StarDate: 
Wednesday, October 18, 2017
Teaser: 
A giant world with a difference



Uranus at Opposition

Wed, 18 Oct 2017 05:00:00 +0000

The planet Uranus is putting in its best appearance of the year this week. It rises at sunset and remains in the sky all night. It’s also closest to us for the year. It’s still so faint, though, that you need binoculars to find it.




Sniffing Venusian Air

Tue, 17 Oct 2017 05:00:00 +0000

A Soviet stamp commemorates the flight of Venera 4, which parachuted through the atmosphere of Venus in October 1967. It made the first direct measurements of the atmosphere of any planet beyond Earth, determining that Venus's "air" consists mainly of carbon dioxide. It also measured high temperatures and pressures before its battery died at an altitude of about 15 miles. [Wikimedia]

 

(image)



Moon and Venus

Tue, 17 Oct 2017 05:00:00 +0000

Sniffing Venusian Air A Soviet stamp commemorates the flight of Venera 4, which parachuted through the atmosphere of Venus in October 1967. It made the first direct measurements of the atmosphere of any planet beyond Earth, determining that Venus's "air" consists mainly of carbon dioxide. It also measured high temperatures and pressures before its battery died at an altitude of about 15 miles. [Wikimedia]   The beautiful “morning star” shines above the crescent Moon at dawn tomorrow. It’s not a star at all, though — it’s Venus, our nearest planetary neighbor. It shines so brightly in part because its surface is completely covered by clouds. They hide not only the surface, but the planet’s atmosphere as well. In fact, scientists got their first direct measurements of the atmosphere half a century ago. Venera 4 was a Soviet spacecraft that arrived at Venus 50 years ago tonight. It dropped a probe into the atmosphere — the first craft to plumb the atmosphere of any planet other than Earth. Venera’s parachute opened at an altitude of more than 30 miles. The probe’s instruments then transmitted readings for an hour and a half, until Venera reached an altitude of about 15 miles. Because of the cloud cover, there was no consensus on what Venera 4 would find. Estimates of surface temperature and pressure, along with the atmosphere’s composition, varied wildly. The probe put a lot of that uncertainty to rest. By the time it stopped working, atmospheric pressure was already more than 20 times the surface pressure on Earth, and temperatures had reached 530 degrees Fahrenheit. And Venera found that carbon dioxide made up more than 90 percent of the atmosphere. Several later missions made it all the way to the surface, providing a more complete picture of Venus’s atmosphere — a hot, dense, toxic brew hiding beneath a beautiful blanket of clouds.   Script by Damond Benningfield Keywords: Soviet/Russian Space ProgramSpace ExplorationVenusVenusian SurfaceStarDate: Tuesday, October 17, 2017Teaser: Dropping in on a neighbor [...]



Moon and Venus

Tue, 17 Oct 2017 05:00:00 +0000

The beautiful “morning star” shines above the crescent Moon at dawn tomorrow. It’s not a star at all, though. Instead, it’s Venus, our nearest planetary neighbor. It shines so brightly in part because its surface is completely covered by clouds.




Moon and Mars

Mon, 16 Oct 2017 05:00:00 +0000

Earth’s geologic history is divided into several eras. Today, we’re in the Cenozoic era, which began about 66 million years ago.

The current geologic era on Mars has been going on a lot longer. Known as the Amazonian period, it’s been underway for three billion years. That means that not much has changed on the planet during that time.

During earlier eras, the Martian surface changed quickly. Rivers flowed across the landscape, carving channels and canyons. They filled lakes and seas, and perhaps even an ocean. There was a lot of volcanic activity as well.

By the start of the Amazonian, though, things were slowing down. Mars had cooled off, so some of its water froze. But much of the water escaped into space, because Mars’s weak gravity couldn’t hold on to the planet’s atmosphere. Without an atmosphere, standing water vaporized, water molecules were split apart by sunlight, and the hydrogen in the water was whisked away by the solar wind.

That doesn’t mean things have been static over that period, though. Volcanic activity continued, and winds in the thin atmosphere sculpted the landscape — a process that’s still going on. Yet Mars is much quieter than it was during its youth — a world little changed over most of its long history.

And Mars is in good view at dawn tomorrow. It stands to the right of the crescent Moon, and looks like a moderately bright star. The much brighter planet Venus stands below them. More about that tomorrow.

 

Script by Damond Benningfield

StarDate: 
Monday, October 16, 2017
Teaser: 
A long period of quiet on Mars



Moon and Mars

Mon, 16 Oct 2017 05:00:00 +0000

The planet Mars is in good view at dawn tomorrow. It stands to the right of the crescent Moon, and looks like a moderately bright star. The much brighter planet Venus stands below them.




Surprising Monster

Sun, 15 Oct 2017 05:00:00 +0000

The giant galaxy UGC 1382, which is in the constellation Cetus, the sea monster, is a bit of a surprise. At visible wavelengths alone (left), it looks like a dull elliptical galaxy, which has already used up all of its gas and is no longer giving birth to new stars. A few years ago, though, scientists took a closer look at it in ultraviolet wavelengths (center), which revealed bright spiral arms around the galaxy's core. Adding radio wavelengths (right, in green) reveals massive clouds of hydrogen gas around the galaxy, indicating that it has plenty of materials for making many more stars. [NASA/JPL/Caltech/SDSS/NRAO/L.Hagen and M.Seibert]

 

(image)



Monster Galaxy

Sun, 15 Oct 2017 05:00:00 +0000

Surprising Monster The giant galaxy UGC 1382, which is in the constellation Cetus, the sea monster, is a bit of a surprise. At visible wavelengths alone (left), it looks like a dull elliptical galaxy, which has already used up all of its gas and is no longer giving birth to new stars. A few years ago, though, scientists took a closer look at it in ultraviolet wavelengths (center), which revealed bright spiral arms around the galaxy's core. Adding radio wavelengths (right, in green) reveals massive clouds of hydrogen gas around the galaxy, indicating that it has plenty of materials for making many more stars. [NASA/JPL/Caltech/SDSS/NRAO/L.Hagen and M.Seibert]   Astronomers got quite a surprise recently. What they thought was a fairly ordinary galaxy turned out to be one of the largest galaxies they’d ever seen. UGC 1382 had been classified as an elliptical galaxy — a type that no longer gives birth to new stars. But a closer look revealed an enormous disk of stars around the galaxy’s center. The disk includes spiral arms that are giving birth to new stars. The stars are so spread out, though, that the disk is hard to see. Our galaxy, the Milky Way, is also a giant spiral. Its disk of stars spans more than a hundred thousand light-years. But UGC 1382’s disk is more than 500,000 light-years across — several times the diameter of the Milky Way’s disk. The galaxy doesn't stop there, though. Beyond the stellar disk is a disk of gas, just as there is in the Milky Way. When you count that, UGC 1382 is a whopping 700,000 light-years across. That’s nearly a third of the distance between the Milky Way and the Andromeda galaxy, the closest big galaxy to our own. Gargantuan though this galaxy is, it isn’t unique. Three decades ago, astronomers found a similar galaxy, Malin 1. But UGC 1382 is much closer. That will make it easier for astronomers to study — and figure out how such a monster galaxy came to be. Appropriately enough, this galactic monster is in Cetus, which represents a sea monster. It clears the horizon in late evening, spanning much of the southeastern quadrant of the sky.   Script by Ken Croswell, Copyright 2017 Keywords: GalaxyStarDate: Sunday, October 15, 2017Teaser: A monster within a monster [...]



Andromeda Galaxy

Sun, 15 Oct 2017 05:00:00 +0000

The Andromeda galaxy is in good view right now. Tonight, it’s in the east-northeast as darkness falls, and overhead later on. It looks like a faint, fuzzy star. Small telescopes reveal its true nature: a family of hundreds of billions of stars.




Moon and Regulus

Sat, 14 Oct 2017 05:00:00 +0000

Regulus is a big star — it’s three times the Sun’s diameter. Even so, the heart of the lion will wink out of sight in an instant early tomorrow for skywatchers across almost all of the United States.

Nothing is happening to the star itself. Instead, it’ll be covered by the crescent Moon — an event known as an occultation. It’s one of a series of occultations that began last December and will continue through April.

The Moon can occult Regulus because the star lies right on the ecliptic, which is the Sun’s path across the sky. The Moon stays close to that path, too. But the Moon’s orbit is tilted a bit with respect to the ecliptic. So most months, the Moon misses Regulus.

In fact, it misses the star most years as well. That’s because the Moon veers back and forth across the ecliptic over a period of years. So its occultations of Regulus come in clumps — when the Moon’s position relative to the ecliptic is just right.

This occultation begins in the wee hours of the morning — around 5:45 a.m. from New York, and earlier as you move farther west. Regulus will disappear behind the lighted portion of the Moon, then return to view from the dark portion. The occultation will last about 30 minutes to an hour, with Regulus remaining hidden longer from more southerly latitudes.

Those on the Pacific coast won’t see the occultation at all — it’ll be over by the time the Moon and Regulus rise, with the bright star standing just above the Moon.

 

Script by Damond Benningfield

StarDate: 
Saturday, October 14, 2017
Teaser: 
A big star disappears from view



Moon and Regulus

Sat, 14 Oct 2017 05:00:00 +0000

Regulus will wink out of sight early tomorrow across most of the U.S. The star will be covered by the crescent Moon, an event known as an occultation. It’s one of a series of occultations that began last December and will continue through April.




Capricornus

Fri, 13 Oct 2017 05:00:00 +0000

The roster of constellations includes some weird and wonderful creatures. There’s a dragon, a unicorn, and two centaurs. But perhaps the weirdest of all is Capricornus, the sea-goat. It’s half goat and half fish.

In Greek mythology, it’s associated with the god Pan, who was half goat and half man. The story says that he was about to be attacked by the monster Typhon, so he jumped into the water to escape. At the same time, he tried to transform himself into a fish to speed his getaway. But he botched the spell, and turned his human half into a fish, but kept the half that was a goat.

The constellation is low in the southern sky as darkness falls at this time of year. Its brightest stars form a wide triangle. None of the sea-goat’s stars is especially bright, though, so you need a fairly dark sky to make them out.

The brightest forms the left point of the triangle. It’s known as Deneb Algedi — “the tail of the goat.” It’s actually a system of at least two stars. The leader is about twice as big and heavy as the Sun, and shines several times brighter. The other is quite similar to the Sun.

The two stars orbit each other about once a day. As they do so, each star passes in front of the other for a bit. When the fainter star crosses the brighter one, the system’s overall brightness drops by about a quarter. That’s just enough for a skilled observer to notice with the eye alone — a slight flicker for one of the night sky’s oddest creatures.

 

Script by Damond Benningfield

StarDate: 
Friday, October 13, 2017
Teaser: 
The weird and wonderful sea-goat



Capricornus

Fri, 13 Oct 2017 05:00:00 +0000

Capricornus, the sea-goat, is low in the southern sky as darkness falls at this time of year. Its brightest stars form a wide triangle. None of the sea-goat’s stars is especially bright, though, so you need a fairly dark sky to make them out.




Protecting Earth

Thu, 12 Oct 2017 05:00:00 +0000

When a double asteroid swings close to Earth in 2024, it just might get a nasty reception. NASA is studying a mission that would slam a spacecraft into the smaller of the two bodies. Astronomers would then measure how much the impact affected the orbit of the two asteroids around each other — vital information that could help us deflect an asteroid on a collision course with Earth. An impact by a large asteroid could have devastating effects across a region or even the entire planet. But with enough lead time, it could be possible to nudge an asteroid onto a safe course. One way to provide the nudge might be to ram into the asteroid, changing its speed and direction by a tiny bit. The new mission, known as DART, would test that technique. The current concept calls for it to target Didymos, a system of two asteroids that orbit the Sun as a pair, bound by their mutual gravitational pull. The larger body is about half a mile in diameter, while the other is only about 500 feet across. DART would hit the smaller asteroid at about 13,000 miles per hour. That should alter the asteroid’s orbit around its companion just enough for astronomers to measure the change. NASA gave the okay to begin preliminary design work on the mission back in June. If DART is launched, it could be a first step in developing a way to protect our planet from potentially deadly space rocks. Tomorrow: odd but beautiful Capricornus, the sea-goat.   Script by Damond Benningfield Keywords: AsteroidImpacts and Impact CratersNASA and the American Space ProgramSpace ExplorationStarDate: Thursday, October 12, 2017Teaser: Protecting Earth from space rocks[...]



Last-Quarter Moon

Thu, 12 Oct 2017 05:00:00 +0000

The Moon is at its last-quarter phase at 7:25 a.m. CDT, so sunlight illuminates half of the lunar hemisphere that faces Earth. The illuminated portion of that hemisphere will grow smaller each day until the Moon is new on October 19.




Tracking Trouble

Wed, 11 Oct 2017 05:00:00 +0000

A small asteroid will pass about 30,000 miles from Earth late tonight. Astronomers are tracking it to learn more about the asteroid and its orbit around the Sun. Plotting its orbit will let us know if the asteroid could hit Earth over the next few decades.

Asteroid 2012 TC4 is about the size of a house. That’s not as big as the asteroid that exploded over Russia back in 2013. So it most likely wouldn’t do much damage even if it did hit us — it would burn up or explode high in the atmosphere.

Many other asteroids that pass close to Earth are much bigger. If one of them hit us, it could cause damage on a local, regional, or even global scale. So astronomers have been scanning the skies for such asteroids for a quarter of a century.

They say they’ve found most of the ones that could cause global damage. Now they’re trying to find the ones that could cause more localized problems. Finding an asteroid long before it hits Earth could give us time to deflect it; more about that tomorrow.

2012 TC4 gives the asteroid-tracking networks a chance to refine their skills. So astronomers have been monitoring it since it got close enough and bright enough for them to see it clearly.

The asteroid will pass closest to Earth at 12:42 a.m. Central Time tomorrow. As astronomers track it, they’ll learn more about its size, mass, and composition — critical factors in determining how much of a threat any space rock poses to our planet.

 

Script by Damond Benningfield

StarDate: 
Wednesday, October 11, 2017
Teaser: 
A close encounter with an asteroid



Tracking Trouble

Wed, 11 Oct 2017 05:00:00 +0000

Asteroid 2012 TC4 will pass about 30,000 miles from Earth tonight. Astronomers are tracking it to learn about the asteroid and its orbit. 2012 TC4 is about the size of a house, which is smaller than the asteroid that exploded over Russia in 2013.




Catching Showers

Tue, 10 Oct 2017 05:00:00 +0000

Several well-known meteor showers punctuate this month’s night skies. Most of them produce only a handful of “shooting stars” per hour, so there’s not much to see. And even the best of them generate no more than a score of meteors per hour, and only for a short time.

Astronomers have also compiled a list of possible meteor showers — more than 300 spread throughout the year. And they’re using networks of automated cameras and telescopes to try to confirm them. The observations will help the astronomers identify the objects that cause the showers.

A meteor shower occurs when Earth flies through the orbital path of a comet or asteroid, which sheds bits of debris as it orbits the Sun. These particles ram into the atmosphere at tens of thousands of miles per hour, forming the streaks of light known as meteors.

A California-based network known as CAMS has hundreds of cameras in the United States, western Europe, Africa, and elsewhere. If two or more cameras spot the same meteor, scientists can triangulate the observations to trace where the meteor came from. Meteors that come from the same direction in space, at the same time of year and at the same speed, probably came from a single object, so they form a meteor shower.

These observations can help scientists forecast future meteor showers. Among other things, that could help protect orbiting spacecraft from damage by tiny space rocks.

We’ll talk about a bigger space rock tomorrow.
 

Script by Damond Benningfield
 

Keywords:

StarDate: 
Tuesday, October 10, 2017
Teaser: 
Tracking down meteor showers



Rho Cassiopeia

Tue, 10 Oct 2017 05:00:00 +0000

Rho Cassiopeia, one of the largest stars in the galaxy, stands to the right of the “W” outlined by Cassiopeia, which is in the northeast at nightfall. The star, which is visible to the unaided eye, eventually will blast itself apart as a supernova.




Bright Visitor

Mon, 09 Oct 2017 05:00:00 +0000

A brilliant meteor streaked across part of the United States on the evening of October 9, 1992, with a small chunk of it smashing into a parked car in Peekskill, New York. Because it was a Friday night, it was viewed by thousands of fans at high school football games. Their reports, along with videos shot by at least 16 people, helped scientists trace the disintegrating space rock's path (shown here). [Meteorite Action]

(image)



Peekskill Meteorite

Mon, 09 Oct 2017 05:00:00 +0000

Bright Visitor A brilliant meteor streaked across part of the United States on the evening of October 9, 1992, with a small chunk of it smashing into a parked car in Peekskill, New York. Because it was a Friday night, it was viewed by thousands of fans at high school football games. Their reports, along with videos shot by at least 16 people, helped scientists trace the disintegrating space rock's path (shown here). [Meteorite Action] High-school student Michelle Knapp was watching TV at her parents’ house in Peekskill, New York, when she heard what sounded like a three-car pile-up outside. When she checked, though, she saw only one damaged car: her own. The 1980 Chevrolet Malibu had a crumpled bumper and trunk. And beneath it was a warm rock the size of a bowling ball, partially embedded in the gravel driveway: a 26-pound space rock that had fallen to Earth. It happened 25 years ago tonight, at the end of a fiery plunge through the atmosphere The glowing streak was visible for about 40 seconds. Because it was a Friday night, thousands of high school football fans saw it. And at least 16 of them recorded it on video. That allowed scientists to trace its path across the sky, and calculate some details about the original rock. They determined, for example, that it was traveling at 33,000 miles per hour when it hit the atmosphere. It was a few feet across, and probably weighed between 10 and 25 tons. It broke up as it traveled over Kentucky, with the fragments racing northeastward. Most of the original rock vaporized during its entry into the atmosphere. The surviving bits of rock probably were scattered across thousands of square miles. But the biggest and most famous piece landed in Peekskill. Michelle Knapp sold the Malibu and the meteorite for tens of thousands of dollars — a windfall from a “falling star.” More about meteorites tomorrow.   Script by Damond Benningfield  Keywords: Meteors and MeteoritesStarDate: Monday, October 9, 2017Teaser: An unusual auto collision [...]



Evening Stars

Mon, 09 Oct 2017 05:00:00 +0000

As twilight fades away this evening, the stars slowly fade in. The first stars to pop into view include yellow-orange Arcturus, fairly low in the west; ruddy Antares, quite low in the southwest, and the three stars of the Summer Triangle high overhead.




Moon and Aldebaran

Sun, 08 Oct 2017 05:00:00 +0000

For Aldebaran, it’s the beginning of the end. The bright orange star stands to the lower left of the Moon as they rise late this evening, and even closer to the upper left of the Moon at first light tomorrow. Aldebaran has completed its long run in the prime of life and now is in the early stages of its demise. This process will end in a few hundred million years, when all that remains will be the star’s dead core. Right now, the core is in a holding pattern. Nuclear reactions have converted its original hydrogen to helium. Reactions are still taking place in a thin layer around the core, but not in the core itself. The core is shrinking and getting hotter, causing Aldebaran’s outer layers to expand and cool. In fact, Aldebaran is more than 40 times wider than the Sun. Over millions of years, the core will get hot enough to ignite nuclear reactions in the helium. The outer layers will shrink a bit while Aldebaran burns through the helium. When the helium in the core runs out, the star will briefly get its energy from shells of helium and hydrogen around the core. As the hydrogen and helium take turns switching on and off, Aldebaran will pulse in and out like a beating heart. Each pulse will expel some of the star’s gas into space. Eventually, all the gas in the outer layers will stream into space, forming a colorful cocoon of gas and dust. This cocoon will quickly dissipate — leaving only the star’s hot but dead core.   Script by Damond Benningfield   Keywords: AldebaranLifecycle of StarsNuclear FusionStarDate: Sunday, October 8, 2017Teaser: The beginning of the end for a bright star[...]



Moon and Aldebaran

Sun, 08 Oct 2017 05:00:00 +0000

Bright orange Aldebaran, the eye of the celestial bull, stands to the lower left of the Moon as they rise late this evening, and even closer to the upper left of the Moon at first light tomorrow.




Fomalhaut

Sat, 07 Oct 2017 05:00:00 +0000

Every star in the night sky looks like nothing more than a dot against the darkness of space. Some are brighter than others, and some show a bit of color, but they’re all still just pinpoints of light. As modern telescopes allow us to zoom in more closely, though, we see that there’s a lot more to a star system than meets the eye. An example is Fomalhaut, the leading light of Piscis Austrinus, the southern fish. It’s low in the southeast at nightfall, and at its highest, due south, a few hours later. It’s pretty bright, and there are no other bright stars around it, so it stands out. Fomalhaut itself is bigger, heavier, and brighter than the Sun, and billions of years younger. It’s surrounded by a disk of debris that spans tens of billions of miles. Much of it consists of grains of dust coated with ice that are warmed by Fomalhaut, causing the disk to glow in the infrared. But the disk also contains lots of icy comets and rocky asteroids. They stage frequent collisions, renewing the supply of material in the disk. The disk also contains a giant planet. It’s been photographed by Hubble Space Telescope, although all we see is a small orange dot. The planet follows an elongated orbit around Fomalhaut. That may mean that another planet that’s closer to the star is pushing the visible planet around. That would give the system at least two planets, plus a vast cloud of debris — meaning there’s a lot more to Fomalhaut than meets the eye.   Script by Damond Benningfield   Keywords: ExoplanetHubble Space TelescopePiscis Austrinus, the Southern FishStarDate: Saturday, October 7, 2017Teaser: The busy environs of a bright star[...]



Fomalhaut

Sat, 07 Oct 2017 05:00:00 +0000

Fomalhaut, the leading light of Piscis Austrinus, the southern fish, stands low in the southeast at nightfall, and at its highest, due south, a few hours later. It’s bright, and there are no other bright stars around it, so it stands out.