NASA’s Total Solar Eclipse Maps Show Best Viewing Spots (Photos)


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NASA’s Total Solar Eclipse Maps Show Best Viewing Spots (Photos)

Path of a solar eclipse

Credit: NASA

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Gorgeous Crater Lake Stuns in This Photo from Space


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Gorgeous Crater Lake Stuns in This Photo from Space

Crater Lake, the deepest lake in the United States, was formed after eruption and collapse of Mount Mazama 7,700 years ago.

Credit: NASA Earth Observatory

Southern Oregon’s idyllic Crater Lake — snow ringed and shade dappled — belies its violent past.

This image, taken by an astronaut aboard the International Space Station, was released July 31 by NASA’s Earth Observatory. Crater Lake’s midnight-blue waters are mottled only by the shadows cast by clouds and Wizard Island (at right of the frame), stippled in snow.

The caldera — the volcanic bowl of the lake — was formed 7,700 years ago after the volcano Mount Mazama erupted, spewing pumice and ash skyward, reaching heights of up to 30 miles (50 kilometers). The excess of magma then caused the volcano to collapse. Rain and snow filled the caldera, outpacing the lava that continued to flow from further smaller eruptions, until the lake was formed, according to the United States Geological Survey. [The 10 Biggest Volcanic Eruptions in History]

The Wizard Island peak —which science teacher Tom McDonough observed in one of the Crater Lake Institute’s Nature Notes From Crater Lake “somehow seems fitting to have a winged dinosaur fly in circles around the cone” —is one of the only remnants of the volcano’s fiery past that can be seen above the surface. Further clues, however, remain along the lake floor. In 2000, scientists conducted a bathymetry survey, a study of the topography of the lake bottom, which revealed that the lake’s depths contain a lava dome, cone and traces of a landslide.

Other crater lakes have similarly tumultuous histories. The supervolcano that formed the vast Indonesian Lake Toba 75,000 years ago spewed ash more than 4,350 miles (7,000 km), about the distance between Chicago and Hawaii. More recently, the 1991 eruption of Mount Pinatubo in the Philippines not only unleashed a 100-mile-wide (160 km) cloud of ash, but also created hot ash avalanches and enormous mudflows. This powerful eruption created the caldera that now contains serene Lake Pinatubo.

Original article on Live Science.

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Do Other Planets Have Solar Eclipses?


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Do Other Planets Have Solar Eclipses?

The Mars rover Curiosity took these images of an annular, or ring, eclipse as Mars’ largest moon, Phobos, passed directly in front of the sun on Aug. 20, 2013. The photos were taken 3 seconds apart.

Credit: NASA/JPL-Caltech/Malin Space Science Systems/Texas A&M University

As Earthlings, we have the privilege of ooohing and aaahing at total solar eclipses, those dazzling celestial events in which the moon blocks the sun’s light from hitting our planet. But is Earth the only world in our solar system that experiences this spectacular phenomenon?

The answer is no. Total solar eclipses can happen on other planets too, as long as they have moons that are big enough to cover the sun’s disk from the planet’s perspective and orbit the planet on the same plane as the sun, astronomers told Live Science.

A total solar eclipse occurs when a planet, its moon and the sun are aligned along the same plane, and a substantially sized moon passes between the planet and its sun, totally blocking the sun’s light from reaching the planet.

“To get a solar eclipse, the first thing you need is a moon,” said Christa Van Laerhoven, a postdoctoral fellow of astronomy at the University of British Columbia in Canada. “This immediately rules out solar eclipses on Mercury or Venus” — two planets without moons, she said. [What Would Earth Be Like with Two Suns?]

Mars has two moons — Phobos and Deimos — but both are too small to create total solar eclipses that would be visible from the Red Planet. Rather, these moons can make partial eclipses for any potential life-form (or Mars rover) watching from the ground, Van Laerhoven said.

“The view from those little moons is more interesting: They see Mars eclipsing the sun very frequently, and during some seasons, it happens every day,” astronomer Matija Cuk wrote on the Cornell University blog “Ask an Astronomer.”

The gas giants — Jupiter, Saturn, Uranus and Neptune — can all have total solar eclipses, as they have large moons and the sun appears small to them, Cuk said. But because these planets are made of gas, it would be impossible to stand on them and see such solar eclipses, he said.

However, if you had a special spaceship that could hover near the swirling gas giants, you could very well glimpse a solar eclipse. Jupiter has up to 67 moons, including Ganymede, the largest moon in the solar system. Because Jupiter’s moons orbit on the same plane as the sun, the planet can have solar eclipses, Cuk and Van Laerhoven said.

In fact, if you could land on one of Jupiter’s moons, you could see its other moons eclipse the sun, the astronomers said.

But what about dwarf planets, such as Pluto? “It seems likely that Charon [Pluto’s largest moon] produces total solar eclipses for Pluto,” Van Laerhoven said. But because the same side of Pluto and Charon always face each other, “only one side of both Pluto and Charon will ever experience eclipses,” Cuk wrote.

On Earth, the moon is almost perfectly suited to making eclipses. The moon is the right size — that is, it appears to be the same size or larger than the apparent size of the sun, as seen from Earth. “This means that when the moon passes in front of the sun, the photosphere [the sun’s luminous outer shell] gets covered, but the corona [the sun’s upper atmosphere] remains visible,” Van Laerhoven said. [Why Total Solar Eclipses Are Total Coincidences]

She noted that Earth’s moon is slowly moving farther away from our planet, so in the distant future, the moon’s apparent size will be too small to entirely cover the sun, at least from Earth’s perspective. This means that one day, the moon won’t be able to cause total solar eclipses but only annular eclipses, in which a “ring” of the sun’s disk is still visible, Van Laerhoven said. Experts speculate that Earth will experience its last total solar eclipse about 600 million years from now.

For now, however, the moon is in prime location to cause a total solar eclipse.

“The reason we don’t get solar eclipses every month is because the moon’s orbital plane is slightly misaligned from Earth’s orbital plane around the sun,” Van Laerhoven said. “If they are misaligned, that decreases your chances of having a solar eclipse. You only get it when things happen to be lined up.”

REMEMBER: Looking directly at the sun, even when it is partially covered by the moon, can cause serious eye damage or blindness. NEVER look at a partial solar eclipse without proper eye protection. Our sister site Space.com has a complete guide for how to view an eclipse safely.

Original article on Live Science.

10 Hypothetical Astronomical Objects That Could Actually Exist


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10 Hypothetical Astronomical Objects That Could Actually Exist

PAULINA DESTARAC JULY 24, 2017

http://listverse.com/2017/07/24/10-hypothetical-astronomical-objects-that-could-actually-exist/

Space has undoubtedly been a fascinating part of reality for humanity. Ever since we were able to understand our surroundings, we’ve looked up at the stars in search for answers, inspiration, and constancy. Space has been the muse for hundreds of movies and thousands of books. It has inspired calendars and horoscopes that detail how the arrangement of astronomical objects can predict personality traits and major life events.

Space has also inspired numerous visions of the future. We’ve conjured up scenarios of interplanetary travel, alien communication, and even time travel via wormholes. The items on this list look like they have been taken from an old science fiction book. However, numerous scientists believe these objects could exist somewhere in the vastness of space. Here are the top ten hypothetical astronomical objects that could actually exist.

10Zombie Star

Photo credit: NASA, ESA

As the name suggests, this type of star is one that, in a way, comes back from the dead. We’ve all heard of a supernova being referred to as the “death” of a star. In most cases, supernovae do mark the end of stars’ lives, since, during those grand explosions, the star is completely obliterated. However, scientists at NASA now believe that a faint supernova could leave behind a surviving portion of the dying dwarf star.

Astronomers first thought about the possibility of zombie stars when they observed a faint blue star feeding energy to its larger companion star. This process ignited a relatively small supernova, a Type Iax, which is low in brightness and does not spew out as much stellar mass as its cousin, the Type Ia supernova. So far, this is the only known way a white dwarf can explode. Typically, stars that explode at the end of their lifetimes are large, massive, and have very short life spans. White dwarfs, on the other hand, are cooler and tend to live longer, since they do not typically explode. Instead, they tend to expel their mass and create a planetary nebula. NASA scientists believe they have identified 30 of these Type Iax supernovae that leave behind a surviving white dwarf, but additional evidence is needed to safely say that they exist.

9White Hole


White holes were theorized by scientists who were working with black holes. While they were working through the complex mathematics associated with black holes, they found that by assuming the singularity at the center of a black hole had no mass, or by assuming that there was no mass within the event horizon, a white hole could be created.

The math explains that if white holes are real, they would behave exactly unlike black holes. That is, instead of sucking up all the matter around them, they would eject matter into the universe. However, the math also states that white holes could only exist if there was absolutely no matter inside the event horizon, not even a tiny cookie crumb. In the instance one atom of matter enters the white hole’s event horizon, it would collapse and disappear, so even if these white holes existed in the beginning of our universe, their life spans would have been incredibly short, since our universe is filled with matter.

8Dyson Sphere


The concept of a Dyson sphere was first introduced by Freeman Dyson, a physicist and astronomer who explored the idea through a thought experiment. He imagined a solar system–sized solar power collector. He believed a civilization could enclose its star in a cloud of satellite-type objects (or a “shell” or “ring of matter” in Dyson’s words) in order to beam 100 percent of the star’s radiation to a planet. Dyson created this thought experiment as a way to identify possible alien life in the universe. If we were to find a Dyson sphere, it could indicate the presence of a highly advanced alien civilization.

Here’s a cool fact: If we had the technology to create a Dyson sphere around the Sun, we would generate 384 yottawatts of energy, aka the total power output of the Sun. (Yotta- is the largest decimal unit prefix. It is equal to ten to the 24th power, or one septillion, or one million million million million.)

7Black Dwarf


Black dwarf—the name itself does not invoke sci-fi vibes as “zombie star” does. However, the concept behind a black dwarf is equally as interesting as all the other hypothetical objects on this list. So far, astronomers have found white dwarfs, brown dwarfs, and red dwarfs. However, black dwarfs have never been seen and are purely theoretical. Astronomers believe they could be formed from white dwarfs that have cooled for a sufficiently long time, to the point where their temperature matches the temperature of the Cosmic Microwave Background. The CMB is the radiation left over from the Big Bang that fills up the entire universe. It currently has an average temperature of 2.7 Kelvin.

These black dwarfs are thought to be invisible, since their temperature is so low and they have no internal source of energy. Theoretically, if a 5-Kelvin white dwarf was to turn into a black dwarf, it would take 1015 years.Therefore, the universe is still too young to have created any black dwarfs!

6Quark Star

Photo credit: Science

Quark stars, also called strange stars, are thought to be composed of a soup of quarks—the fundamental constituents of matter. Astronomers believe that these stars can be created after a medium-sized star (about 1.44 times the size of our Sun) has run out of fuel and has entered the collapsing stage of its lifetime. As it collapses, it squeezes protons and electrons together, eventually forming neutrons. However, scientists think that if the star is heavy enough and continues collapsing after this stage, the neutrons that were created could break down into their component quarks under the immense pressure, creating an incredibly dense type of matter.

A paper published in 2012 delves into the hypothetical nature of these strange quark stars. The authors of the paper explain that these stars could be enveloped in a thin nuclear “crust,” consisting of heavy ions immersed in an electron gas. However, they could also exist without the crust. In that case, the quark stars would possess ultra-high electric fields that could reach up to 1019 Volts per centimeter!

5Ocean Planet

Photo credit: Anynobody

As the name suggests, ocean planets, or water worlds, are thought to be composed entirely of vast, uninterrupted oceans. The idea of water worlds became popular when NASA announced the existence of two planets outside of our solar system: Kepler-62e and Kepler-62f. These planets are thought to be water worlds that could harbor a wealth of aquatic life.

A paper published in June 2004 explains how these types of planets could be formed. It is believed that they form relatively far away from their parent star and slowly migrate toward it (over a time period of about a million years). The planet would have to come five to ten times closer to the star, depending on how far away it initially formed. The paper delves into the internal structure of the planets as well as how deep their oceans could be and what their atmospheres could be composed of. Interesting read!

4Chthonian Planets

Photo credit: ESO/L. Calcada

The idea of Chthonian planets became popular thanks to an extrasolar planet nicknamed Osiris. NASA scientists were baffled when they detected carbon and oxygen for the first time in an atmosphere outside of our solar system. However, Osiris’s atmosphere was seen to be rapidly evaporating.

Scientists have designated a new class of worlds called Chthonian planets, which are created when gas giants, like Jupiter, enter a critical distance from their parent star. When they get too close, their outer layers begin to rapidly evaporate. Chthonian planets are thus the remnants of these gas giants, which have been stripped of their outer layers, leaving behind a dense central core.

3Preon Star


A preon star is something that could follow a quark star. As a star is compressed to the point where it becomes a quark star and is still massiveenough to continue its collapse, scientists believe that the quarks themselves could break down into these theoretical preons.

So far, scientists have not found a way to break down quarks, so they remain the main constituents of matter. However, if quarks are made of other individual particles—these so-called preons—stars could technically achieve this even denser state, one of matter created entirely of a soup of hyper-dense preons.

2Ghost Galaxy

Ghost galaxies, also called dark galaxies, are galaxies that have very few stars. They’re so inefficient at making stars that they’re thought to be mostly composed of gas and dust, making them basically invisible. As of now, they remain theoretical for this very fact, but astronomers believe that dark galaxies are likely to exist. An international team of scientists even thinks they have found the first dark galaxy. However, more data analysis needs to be done before it is confirmed.

Astronomers believe they have also found a different type of ghost galaxy, one that is 99 percent dark matter. They named it Dragonfly 44, and it seems to be the Milky Way’s dark doppelganger in mass, but it contains very few stars and is different in its structure. If this galaxy is ever observed or analyzed in enough detail, it could change how astronomers perceive galaxy formation and dark matter.

1Cosmic Strings


Cosmic strings are an insane idea, but the craziest part about them is that they could actually exist. Cosmic strings are slight defects in the fabric of space and time that were created at the beginning of time, left over from the formation of the universe. If one were to interact with one of these defects, one could create a “closed time-like curve,” which would allow for backwardtime travel. Scientists have speculated how they can make time machines out of these cosmic strings. They believe that by putting two of them close enough together, or one string and one black hole, they could create an array of these closed time-like curves.

To better visualize this, picture the cosmic strings as loops of space-time. Imagine picking up one loop and throwing it across space directly toward another loop. Then, imagine jumping on a space ship and flying around them in a perfect figure eight. This would allow you to emerge at any random point in space and time!

Although these objects are purely theoretical, astronomers believe that, if they exist, they would be very small “lines” in the fabric of space, and their effects would be incredibly strange. It is also believed that their existence could explain bizarre effects observed in faraway galaxies.

10 Amazing Discoveries Involving Asteroids


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10 Amazing Discoveries Involving Asteroids

JANA LOUISE SMIT JUNE 7, 2017

http://listverse.com/2017/06/07/10-amazing-discoveries-involving-asteroids/

At first glance, all asteroids look the same and don’t get much attention unless one destroys modern life in a movie. In reality, these ancient space mountains still surprise astronomers with their origins, bizarre behavior, and effects on the planets. In recent years, science has identified unique traits, devastating weather, and amazing individual rocks not even the experts could have predicted.

10Towers Within Craters

Photo credit: Live Science

In 2016, researchers were looking to study cosmic impacts on other worlds. To do this, they chose the Chicxulub crater in Mexico’s Yucatan Peninsula. Said to be the footprint of the asteroid that bumped dinosaurs off the face of the Earth, the crater had one trait that made it useful to study impacts on other planets.

So-called “peak rings” are tall hills circling the center inside of major craters. They exist across the solar system but in only one place on Earth: the epic crash that left an impression 180 kilometers (110 mi) wide across the Yucatan Peninsula. The 65-million-year-old scar was a rare opportunity to study the origin of these structures and revealed how asteroids are capable of violent and dramatic landscaping.

The force of the collision almost pierced Earth’s crust and caused the soil to behave like a thick fluid. Within minutes, deeply buried granite shot up like a water drop following an object dropped in liquid. The rising center reached the height of about 15 kilometers (9 mi) before collapsing downward and outward into a ring of peaks.

9Martian Tornadoes

Photo credit: sciencetimes.com

Asteroid impacts can whip up extreme weather and not just on Earth. In this case, they spawned frightening tornadoes on ancient Mars. Scientists first became aware of this when they studied NASA images and found strange streaks.

The streaks scoured the surface near large craters and were only visible in thermal infrared during Martian nights. A simulated environment was created in a laboratory to find out what caused these unusual surface lines.

Turns out, an asteroid would hit the red planet once in a while. After the asteroid vaporized itself and tons of material from the surface, air was forced from the crater at supersonic speed. Traveling at more than 800 kilometers per hour (500 mph), these plumes surfed just above the surface.

Wherever the flow encountered any raised geography, it created funnels with the strength of an F8 tornado. These scattered storms were responsible for the unusual streaks, leaving trails as they stripped the ground bare. This type of wind phenomenon on Mars is unique to asteroid arrivals and won’t occur again until the next one hits.

8The Olivine Trojans

Photo credit: star.arm.ac.uk

Mars has several companion asteroids that share its orbit. Called Trojans, they come in so-called families that drift around other planets as well, notably a group of 6,000 near Jupiter.

Mars Trojans are unique. So far, nine have been discovered and are the only ones in a stable planetary orbit. They also group together in a way that’s repeated nowhere else in the solar system. Eight keep the same distance from Mars and form the “Eureka family,” named for the asteroid at the nucleus of the cluster.

In 2016, scientists wanted to determine if a common link existed between them and used a spectograph to study three, one being Eureka. By studying the colors that sunlight reflects across the asteroids’ surfaces, their chemical composition could be determined.

The color spectrum turned out to be identical, which is rare enough among asteroids. But even more uniquely, they consisted mostly of olivine. This mineral is evidence that the group is likely ancient remains of the inner mantle of a mini-planet destroyed eons ago.

7The Clovis Killer

Photo credit: Heinrich Harder

When researchers found an abnormal amount of platinum at sites belonging to the Clovis culture, they realized that a long-standing mystery was possibly solved. Around 12,800 years ago, the Clovis Paleoindians suddenly vanished along with over 35 species of Ice Age animals, including the mammoth and saber-toothed tiger.

Scholars aren’t exactly sure why this happened. The unnaturally high deposit of platinum suggested that an impact could be behind it. The scarce metal showed up at 11 archaeological sites linked with the Clovis culture in California, Arizona, New Mexico, Ohio, Virginia, North Carolina, and South Carolina.

Earlier, in 2013, another team found platinum-enriched ice in Greenland dating back to the “Young-Dryas” period. During this era, temperatures mysteriously plummeted and lasted for 1,400 years. It also began around the same time that the Clovis culture disappeared.

While rare on Earth, platinum is abundant in comets and asteroids. All research points to an extinction event that hit North America. Most likely, fragments from a comet or asteroid caused disaster, such as the climate suddenly cooling, on a continental or even global scale.

6The Eternal Fallout

Photo credit: astronomy.com

Earth gets bombarded with around 100 tons of extraterrestrial objects on a daily basis. Luckily, most are microscopic and burn up in the planet’s atmosphere. Those that reach the surface are mostly rocky meteorites called chondrites. Depending on which ancient collision event they were born from, they are classed H, L, or LL. At the moment, the vast majority are types H and L.

To find out what kind of space “rains” occurred on Earth in the distant past, researchers traveled to Russia. Near St. Petersburg exists an area with a rich buildup of such materials dating back to antiquity. Hundreds of samples were taken and chemically tested to determine their type.

Surprisingly, they found a barrage of L-chondrites starting around 466 million years ago. This particular shower is currently still going strong. It began with what must have been an impressive impact involving an asteroid somewhere in the solar system. The resulting fallout on Earth was so thick that it dominated the geological record for a million years, to the point of covering up all other impacts.

5The Lomonosov Tsunamis

Photo credit: National Geographic

A theory suggesting Mars once had water recently received dramatic backup—signs that tsunamis raged across the red surface. Where there are tidal waves, there are oceans, and one probably existed on the northern plains of Mars.

Some three billion years ago, an asteroid hit the area and scooped out the Lomonosov crater, measuring 70 kilometers (43 mi) in diameter. After studying the formations of the landscape, it was determined that a pair of giant tsunamis was forced from the crater at 60 meters per second (197 ft/sec).

The first was 300 meters (985 ft) high and reached land within a few hours. The size, speed, and power of the waves would have been monumental. Tsunamis leave their mark on shorelines, and researchers found these typical deposits at what would have been a Martian beach.

Nearby was another distinctive ground pattern called a thumbprint terrain, which occurs when one set of tsunamis bounce back from the shore and smash into a second set. There’s no other way to explain the evidence other than assuming Mars had a northern ocean that got hit by an asteroid, which then sparked devastating tsunamis.

4The Million-Year Volcanic Eruption

Photo credit: ibtimes.co.in

One rock stimulated the Earth to erupt for as long as a million years. Measuring 15 kilometers (9 mi), it hit Canada 1.85 billion years ago in theSudbury basin. The resulting damage left the second-biggest crater found thus far with a diameter of roughly 150–260 kilometers (93–161 mi).

Since most craters eventually end up being destroyed by geological processes, it’s difficult to study the link between space impactors andvolcanism. However, the Sudbury event left behind a remarkably preserved site that is perfect for this kind of research.

During 2013–2014, scientists climbed into the crater and extracted over a hundred samples from the 1.5-kilometer-thick (0.93 mi) rock layers within. The samples consisted of melted surface material as well as volcanic fragments shaped like crab claws. The peculiar formations resulted when gas inside the superheated rock caused them to explode violently.

The rocks were different enough to show that continual, volatile eruptions produced them. The process lasted an incredibly long time, from hundreds of thousands of years to a million years at most.

3Protoplanet Building Blocks

Photo credit: space.com

The second-largest asteroid in the solar system, Vesta, is special. Apart from being an asteroid, it’s also the last remaining protoplanet from the solar system’s beginnings. Vesta is approximately 525 kilometers (326 mi) wide, but its inner structure doesn’t match that of other asteroids.

Instead, like Earth and Mars, it has a core of iron and nickel and a rocky surface. At one point, a violent impact carved a crater near the southern pole and ejected the Vestoids. One such Vestoid, called 1999 AT10, is unlike any known asteroid. It did not come from the outer crust of its parent but from deep within.

This makes it a priceless find. To even begin to understand how the planets formed around 4.5 billion years ago, the exact thickness of Vesta’s crust needs to be calculated. In turn, this will allow scientists to identify which materials existed at the birth of the solar system and blended to form theprotoplanet.

Since 1999 AT10 came from inside of Vesta, this suggests that the maximum crust breadth is equal to the depth of the crater, which is about 25 kilometers (16 mi) deep.

2The Wrong-Way Asteroid

Photo credit: blastr.com

In 2015, astronomers found a bizarre boulder among Jupiter’s Trojans. Nicknamed “BZ,” it shares Jupiter’s orbit but moves in the opposite direction of every planet, the Sun, and 99.99 percent of solar asteroids. This is calledretrograde motion. But while rare, it’s not unique.

Even so, BZ does something spectacular. Since reversed paths spell an almost inevitable collision, other retrograde asteroids avoid planets. But not BZ. With every orbital lap, it comes dangerously close to Jupiter. No other planet in the solar system owns an asteroid that behaves in this manner.

Remarkably, the plucky asteroid has remained safe for thousands of laps and researchers estimate that it will continue to play its lethal game for at least another million years. Jupiter may represent the greatest threat to BZ. But for now, the gas giant’s gravity also keeps BZ safe.

Every time the pair orbits the Sun, the asteroid passes inside and then outside of Jupiter. Each turn’s gravitational tug cancels out the other, and this keeps the asteroid out of harm’s way.

1Six-Tailed Asteroid

Photo credit: space.com

Comets are famous for their fiery tails, but one asteroid outshines them all. In 2013, the Hubble telescope revealed an unknown phenomenon in the solar system’s asteroid belt—a space rock with tails.

For asteroids to develop comet-like dust trails is unheard of, and incredibly, this one flaunted six glowing tails. Dubbed P/2013 P5, its existence shocked scientists. They were also amazed by the way the beams shifted. When found, the tails were radiating from one side of the asteroid. But within 13 days, they ended up on the complete opposite side.

It would appear that the tails didn’t sprout all at once but in bursts. For this reason, it’s likely that a collision didn’t bring on this change. Rather, it probably occurred because P/2013 P5 started to tumble out of control after experiencing radiation pressure.

This destabilized the asteroid so much that its gravity could no longer hold onto material from the nucleus and surface. The 425-meter-wide (1,400 ft) rock is believed to be a 200-million-year-old fragment of a long-destroyed larger object. So far, P/2013 P5 has lost up to 1,000 tons of dust.

Planet 10? Another Earth-Size World May Lurk in the Outer Solar System


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Planet 10? Another Earth-Size World May Lurk in the Outer Solar System

A planetary-mass object the size of Mars may be lurking in the outer solar system.

Credit: Heather Roper/LPL

A planet-size object may be orbiting the sun in the icy reaches of the solar system beyond Pluto.

Scientists at the University of Arizona’s Lunar and Planetary Laboratory (LPL) have determined that an unseen object with a mass somewhere between that of Earth and Mars could be lurking in the Kuiper Belt, a region beyond Neptune filled with thousands of icy asteroids, comets and dwarf planets.

In January 2016, a separate group of scientists predicted the existence of a Neptune-size planet orbiting the sun far, far beyond Pluto  about 25 times farther from the sun than Pluto is. This hypothetical planet was dubbed “Planet Nine,” so if both predictions are correct, one of these putative objects could be the solar system’s 10th planet.

The so-called “planetary-mass object” described by the scientists from LPL appears to affect the orbits of a population of icy space rocks in the Kuiper Belt. Distant Kuiper Belt objects (KBOs) have tilted orbits around the sun. The tilted orbital planes of most KBOs average out to something called the invariable plane of the solar system.

But the orbits of the most distant KBOs tilt away from the invariable plane by an average of 8 degrees, which signals the presence of a more massive object that warps its surroundings with its gravitational field, researchers said in a study due to be published in The Astronomical Journal.

“The most likely explanation for our results is that there is some unseen mass,” Kat Volk, a postdoctoral fellow at LPL and the lead author of the study, said in a statement. “According to our calculations, something as massive as Mars would be needed to cause the warp that we measured.”

These KBOs act a lot like spinning tops, Renu Malhotra, a professor of planetary sciences at LPL and co-author of the new study, said in the statement.

“Imagine you have lots and lots of fast-spinning tops, and you give each one a slight nudge … If you then take a snapshot of them, you will find that their spin axes will be at different orientations, but on average, they will be pointing to the local gravitational field of Earth,” she said. “We expect each of the KBOs’ orbital tilt angle to be at a different orientation, but on average, they will be pointing perpendicular to the plane determined by the sun and the big planets.”

An artist's impression of the undiscovered, planet-size object in the Kuiper Belt
An artist’s impression of the undiscovered, planet-size object in the Kuiper Belt

Credit: Heather Roper/LPL

It may sound a lot like the mysterious Planet Nine, but the researchers say the so-called planetary-mass object is too small, and too close, to be the same thing. Planet Nine lies 500 to 700 astronomical units (AU) from Earth, and its mass is about 10 times that of Earth. (One AU is the average distance at which Earth orbits the sun — 93 million miles, or 150 million kilometers. Pluto orbits the sun at a maximum distance of just less than 50 AU.)

“That is too far away to influence these KBOs,” Volk said. “It certainly has to be much closer than 100 AU to substantially affect the KBOs in that range.”

Though no planet-size objects have been spotted in the Kuiper Belt so far, the researchers are optimistic that the Large Synoptic Survey Telescope (LSST), which is currently under construction in Chile, will help find these hidden worlds. “We expect LSST to bring the number of observed KBOs from currently about 2,000 to 40,000,” Malhotra said.

“There are a lot more KBOs out there — we just have not seen them yet,” Malhotra added. “Some of them are too far and dim even for LSST to spot, but because the telescope will cover the sky much more comprehensively than current surveys, it should be able to detect this object, if it’s out there.”

Email Hanneke Weitering at hweitering@space.com or follow her @hannekescience. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

NASA’s Parker Solar Probe Mission to Touch the Sun Explained (Infographic)


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NASA’s Parker Solar Probe Mission to Touch the Sun Explained (Infographic)

NASA aims to launch its sun-studying Parker Solar Probe in July 2018.

Credit: Jef Castro/Space.com

NASA’s Parker Solar Probe mission, which is scheduled to launch in July 2018, will come within 3.9 million miles (6.2 million kilometers) of the sun — seven times closer than any other spacecraft ever has.

The specially shielded Parker Solar Probe will have to endure temperatures up to 2,500 degrees Fahrenheit (1,370 degrees Celsius) and solar radiation intensities 475 times higher than we’re used to here on Earth.

If all goes according to plan, the Parker Solar Probe will zoom close to the sun 24 times between 2018 and 2025, gathering a variety of data about the sun’s structure and magnetic and electric fields, as well as the energetic particles cruising near and away from Earth’s star. This information could help researchers solve two longstanding mysteries: How the solar wind is accelerated and why the sun’s outer atmosphere, or corona, is so much hotter than the solar surface, NASA officials have said.

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