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An ancient, meteorite, or achondrite, was discovered in the Sahara desert last year that has now been identified as chunk from a protoplanet that formed before Earth came into existence. The space rock, named EC 002, dates back 4.6 billion years and consists mostly of volcanic rock, leading experts to believe it came from the crust of a very early planet.... ...no asteroid shares the spectral features of EC 002, indicating that almost all of these bodies have disappeared, either because they went on to form the building blocks of larger bodies or planets or were simply destroyed.'

The planets of the outer Solar System are known for being strange, as are their many moons. This is especially true of Triton, Neptune’s largest moon. In addition to being the seventh-largest moon in the Solar System, it is also the only major moon that has a retrograde orbit – i.e. it revolves in the direction opposite to the planet’s rotation. This suggests that Triton did not form in orbit around Neptune, but is a cosmic visitor that passed by one day and decided to stay. ... Triton has a radius, density (2.061 g/cm3), temperature and chemical composition similar to...

Neptune’s moons are ...all are named for gods of the sea, or for the children of Poseidon (which include Triton, Proteus, Depsina and Thalassa), minor Greek water dieties (Naiad and Nereid) or Nereids , the water nymphs in Greek mythology (Halimede, Galatea, Neso, Sao, Laomedeia and Psamathe). Neptune’s Regular Moons are those located closest to the planet and which follow circular prograde orbits that lie in the planet’s equatorial plane. They are, in order of distance from Neptune: Naiad , Thalassa , Despina, Galatea, Larissa , S/2004 N 1, and Proteus. All but the outer two are within Neptune-synchronous orbit......

(NASA/JPL-Caltech) ================================================================================= Life isn't always easy for astrophysicists: just when they've figured out another aspect of the patterns of movement in our Solar System, along come two of the moons of Neptune to mess everything up. The two moons in question are Naiad and Thalassa, both around 100 kilometres or 62 miles wide, which race around their planet in what NASA researchers are calling a "dance of avoidance". Their strange orbit was first detected by NASA researchers in November 2019. Compared with Thalassa, Naiad's orbit is tilted by about five degrees – it spends half of its time above Thalassa...

<p>WASHINGTON (AP) — Uranus is a lopsided oddity, the only planet to spin on its side. Scientists now think they know how it got that way: It was pushed over by a rock at least twice as big as Earth.</p>

<p>Uranus is a lopsided oddity, the only planet to spin on its side. Scientists now think they know how it got that way: It was pushed over by a rock at least twice as big as Earth.</p> <p>Detailed computer simulations show that an enormous rock crashed into the seventh planet from the sun, said Durham University astronomy researcher Jacob Kegerreis, who presented his analysis at a large earth and space science conference this month.</p>

The researchers report that they were studying the planet's rings, which are collectively called Eta, and discovered that they had an oddly shaped orbit -- not round or even circular. Instead, they describe it as sort of triangular. More study showed that the odd orbit of the rings was due to gravitational pull from Cressida -- one of the planet's moons. The gravitational impact is exaggerated, they note, due to the moon keeping pace with the orbit of the planet. The particles in the ring, on the other hand, move faster than the moon. This results in the moon tugging...

Although planets surround stars in the galaxy, how they form remains a subject of debate. Despite the wealth of worlds in our own solar system, scientists still aren't certain how planets are built. Currently, two theories are duking it out for the role of champion. The first and most widely accepted, core accretion, works well with the formation of the terrestrial planets but has problems with giant planets such as Uranus. The second, the disk instability method, may account for the creation of giant planets. "What separates the ice giants from the gas giants is their formation history: during...

Bursts of solar winds caused a huge sparkling region on Uranus, scientists observed this by using Hubble space telescope. Electrons that come from various origins such as solar winds, the planetary ionosphere and moon volcanism, when charged in the form of streams caused this, researchers from the Paris Observatory used the NASA/ESA Hubble Space Telescope to observe this on Uranus. They were able to catch it in powerful magnetic fields and, controlled it into the upper atmosphere, where set off spectacular bursts of light when made interactions with gas particles, such as oxygen or nitrogen.

It’s impossible to do an article about Uranus without opening up the back door to a spit storm of potty humour.... Anyway, perhaps one of the strangest aspects of Uranus is its tilt.... The Earth is tilted 23.5 degrees away from the Sun’s equator. Mars is 25 degrees, and even Mercury is 2.1 degrees tilted.... Uranus is 97.8 degrees... ...[A]stronomers define the angle as greater than 90 degrees when you take its direction of rotation into account. When you describe it as turning in the same direction as the rest of the planets in the Solar System, then you have...

... New research shows that Uranus, a chilly, hostile planet with a number of peculiar features, was the victim of a devastating impact during those early years, and it might explain some of the planet’s strange personality. Uranus moves much differently than the other planets in our Solar System, spinning on its side in comparison to the rest of the worlds in our neighborhood. Astronomers have often wondered just how this happened, but simulations performed by scientists at Durham University’s Institute for Computational Cosmology might have finally produced the answer. “We ran more than 50 different impact scenarios using a...

You might be aware of one of Uranus’ complexities: It spins on its side, and its moons orbit on that same rotated plane. New evidence strengthens the case that Uranus was smashed in a giant collision, resulting in its sideways orientation to its orbital plane and perhaps explaining some of the planet’s other mysteries. A new paper performs a series of simulations on Uranus early in its history, taking note of what an early impact may have done to its rotation rate, atmosphere, and internal structure. The impact could have left a clear signature still visible inside the planet we...

The collision with Uranus of a massive object twice the size of Earth that caused the planet's unusual spin, from a high-resolution simulation using over ten million particles, coloured by their internal energy. Credit: Jacob Kegerreis/Durham University ___________________________________________________________________________ Uranus was hit by a massive object roughly twice the size of Earth that caused the planet to tilt and could explain its freezing temperatures, according to new research. Astronomers at Durham University, UK, led an international team of experts to investigate how Uranus came to be tilted on its side and what consequences a giant impact would have had on the...

The dwarf planet Pluto and its system of five moons are about as mysterious as the underworld of antiquity that inspired their names. ... “We are still baffled by how the system formed,” says study co-author Mark Showalter, a senior research scientist at the Search for Extraterrestrial Intelligence (SETI) Institute. “I think everyone believes that, at some point in the distant past, a large object bashed into ‘proto-Pluto’ and the moons formed out of the debris cloud. However, after that point in the story, details get very sketchy.” Now, analysis of data collected from the Hubble Space Telescope following the...

Asteroid Vesta: The 10th Planet? Discovery Brightens Odds of Finding Another Pluto Nemesis: The Million Dollar Question HOUSTON, TEXAS -- Our solar system may have had a fifth terrestrial planet, one that was swallowed up by the Sun. But before it was destroyed, the now missing-in-action world made a mess of things. Space scientists John Chambers and Jack Lissauer of NASA's Ames Research Center hypothesize that along with Mercury, Venus, Earth, and Mars -- the terrestrial, rocky planets -- there was a fifth terrestrial world, likely just outside of Mars's orbit and before the inner asteroid belt. Moreover, Planet V...

A FIFTH terrestrial planet may once have orbited between Mars and Jupiter. Although gravitational disturbances would have sent the planet hurtling into the sun or out into space long ago, traces of this long-gone world may still be visible in part of the asteroid belt today. Recent simulations have suggested that the gas giants of our solar system formed with circular orbits but moved into their more elongated paths about 4 billion years ago – 700 million years after the solar system formed. While the gas giants were in circular orbits, rocky planets should have formed in stable orbits out...

Scientists used to think that things were pretty chill over in the south hemisphere of Uranus. In fact, they thought it was one of the calmest regions of any of the gas giants. But in analyzing images taken nearly three decades ago by NASA's Voyager-2 spacecraft, researchers think they've found a kerfuffle of activity — which might indicate that there's something unusual about the planet's interior. If you look at these old photos of Uranus, the planet appears to be a stark, featureless ball. And even to scientists, who were able to identify more lively features of the gas giant,...

Scientists have made a stunning discovery in the outer realm of the solar system — an asteroid with its own set of rings that orbits the sun between Saturn and Uranus. The space rock is the first non-planetary object ever found to have its own ring system, researchers say. The pair of space rock rings encircle the asteroid Chariklo. They were most likely formed after a collision scattered debris around the asteroid, according to a new study unveiled today (March 27). The asteroid rings also suggests the presence of a still-undiscovered moon around Chariklo that's keeping them stable, researchers said....

Astronomers from York University in Canada have identified an undocumented type of quasar where gas appears to be getting sucked into a black hole. This may not sound surprising, but current theories say that isn't supposed to happen. Quasars are hyperactive and extremely bright discs of hot gas that surround supermassive black holes. They're also known as galactic nucleuses. The Milky Way has one at its center. All the junk that's rapidly spinning down the drain hole forms a compact disc with a radius that's larger than Earth's orbit around the Sun and a temperature that's hotter than the surface...

Martin Bizzarro of the University of Copenhagen and his colleagues set out to determine the amount of iron in the early solar system. To do so, they measured nickel-60, a decay product of iron-60, in eight meteorites known to have formed at different times during the first 3 million years of the solar system. The meteorites that formed more than about a million years after the start of the solar system contain significantly more nickel-60 than do those that formed earlier, the team found. In a neighborhood of young stars, only a supernova could have produced iron-60, the parent of...