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There's a "dark impactor" blasting holes in our galaxy. Stellar streams are lines of stars moving together across galaxies, often originating in smaller blobs of stars that collided with the galaxy in question. Under normal conditions, the stream should be more or less a single line, stretched out by our galaxy's gravity, she said in her presentation. Astronomers would expect a single gap in the stream, at the point where the original globular cluster was before its stars drifted away in two directions. But Bonaca showed that GD-1 has a second gap. And that gap has a ragged edge —...

2015 TG387, a newfound object in the far outer solar system, way beyond Pluto. The orbit of 2015 TG387 shares peculiarities with those of other extremely far-flung bodies, which appear to have been shaped by the gravity of a very large object in that distant, frigid realm — the hypothesized Planet Nine, also known as Planet X. "These distant objects are like breadcrumbs leading us to Planet X," And 2015 TG387 is special among these bread crumbs, because it was found during a relatively uniform survey of the northern and southern skies rather than a targeted hunt for clustered objects...

A rogue, planet-size object 20 light-years away from Earth has stunned astronomers with its incredibly powerful magnetic field. The scientists found that the object's magnetic field is more than 200 times stronger than Jupiter's, which, in turn, is between 16 and 54 times stronger than Earth's, according to NASA. How the object, which scientists call SIMP J01365663+0933473, can maintain a magnetic field so strong, as well as generate spectacular auroras, is still unclear. "This particular object is exciting because studying its magnetic dynamo mechanisms can give us new insights on how the same type of mechanisms can operate in extrasolar...

A bizarre rogue planet without a star is roaming the Milky Way just 20 light-years from the Sun. And according to a recently published study in The Astrophysical Journal, this strange, nomadic world has an incredibly powerful magnetic field that is some 4 million times stronger than Earth’s. Furthermore, it generates spectacular auroras that would put our own northern lights to shame. The new observations, made with the National Science Foundation’s Karl G. Jansky Very Large Array (VLA), not only are the first radio observations of a planetary-mass object beyond our solar system, but also mark the first time...

Astronomers using the National Science Foundation's Karl G. Jansky Very Large Array (VLA) have made the first radio-telescope detection of a planetary-mass object beyond our Solar System. The object, about a dozen times more massive than Jupiter, is a surprisingly strong magnetic powerhouse and a "rogue," traveling through space unaccompanied by any parent star. "This object is right at the boundary between a planet and a brown dwarf, or 'failed star,' and is giving us some surprises that can potentially help us understand magnetic processes on both stars and planets," said Melodie Kao, who led this study while a graduate...

Conspiracy theorists are claiming that a rogue planet will disrupt Earth’s orbit this Sunday and bring about a series of catastrophic earthquakes that could decimate life as we know it Nibiru, also known as Planet X, was originally supposed to destroy our world on Sept. 23... But that day came and went without an apocalypse in sight.  Now theorists say that Nibiru will come near our planet this weekend and throw off our gravitational forces and with it, bring hellfire and brimstone. Nibiru is a hypothesized planet located on the outer edges of our solar system that allegedly completes one...

The American space agency says that one object is a massive comet, but has so far been unable to identify the other NASA recently spotted two massive space objects hurtling towards Earth. While the American space agency has pinpointed one as a comet, the other has left it slightly more baffled. The comet is set to fly close to Earth this week, but the mystery object isn't expected to make an appearance until February. The object, dubbed "2016 WF9", was detected by NASA's asteroid- and comet-hunting NEOWISE project on 27 November 2016. It is roughly 0.3 to 0.6 miles (0.5...

Astronomers are beginning to glimpse what exoplanets orbiting distant suns are actually like. The trickle of discoveries has become a torrent. Little more than two decades after the first planets were found orbiting other stars, improved instruments on the ground and in space have sent the count soaring: it is now past 2,000. The finds include 'hot Jupiters', 'super-Earths' and other bodies with no counterpart in our Solar System - and have forced astronomers to radically rethink their theories of how planetary systems form and evolve. Yet discovery is just the beginning. Astronomers are aggressively moving into a crucial phase...

A group of astronomers from the US, Europe, Chile and South Africa have determined that 70,000 years ago a recently discovered dim star is likely to have passed through the solar system's distant cloud of comets, the Oort Cloud. No other star is known to have ever approached our solar system this close - five times closer than the current closest star, Proxima Centauri. In a paper published in Astrophysical Journal Letters, lead author Eric Mamajek from the University of Rochester and his collaborators analyzed the velocity and trajectory of a low-mass star system nicknamed "Scholz's star." The star's trajectory...

Astronomers used ESO's Very Large Telescope and the Canada-France-Hawaii Telescope to find CFBDSIR2149, a free-floating planet with the mass of Jupiter that seems to wander through space without orbiting around a star like most planets we know do. In addition, the planet is actually relatively close to our solar system, only 100 light-years away, and offers scientists a more intimate setting to study a planet and its atmosphere. This isn't the first time that a free-floating object has been found in space, but the previous discoveries haven't provided scientists with enough information to label the body as a planet. Instead,...

Researchers say life-bearing planets may exist in vast numbers in the space between stars in the Milky WayA few hundred thousand billion free-floating life-bearing Earth-sized planets may exist in the space between stars in the Milky Way. So argues an international team of scientists led by Professor Chandra Wickramasinghe, Director of the Buckingham Centre for Astrobiology at the University of Buckingham, UK. Their findings are published online in the Springer journal Astrophysics and Space Science. The scientists have proposed that these life-bearing planets originated in the early Universe within a few million years of the Big Bang, and that...

Researchers at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford University estimate that "nomad" planets, ejected from their home stellar system and now free-floating through the Milky Way, could outnumber stars by as many as 100,000 to 1. Earlier estimates were more like a handful to 1, though previous studies have only counted unbound planets more massive than Jupiter. To estimate the number of unbound planets as small as Pluto that could be roaming the galaxy, Louis Strigari (KIPAC), lead author of the study, began with a basic rule of nature: where a few big objects are...

Eighteen rogue planets that seem to have broken all the rules about being born from a central, controlling sun may force a rethink about how planets form, astronomers said on Thursday... "The formation of young, free-floating, planetary-mass objects like these is difficult to explain by our current models of how planets form," Zapatero-Osorio said... They are not linked to one another in an orbit, but do move together as a cluster, she said... Many stars in our own galaxy, the Milky Way, may have formed in a similar manner to the Orion stars, she said. So there could be similar,...

If you can make sense of it, here's the article: Stellar encounters as the origin of distant Solar System objects in highly eccentric orbits SCOTT J. KENYON AND BENJAMIN C. BROMLEY The Kuiper belt extends from the orbit of Neptune at 30 AU to an abrupt outer edge about 50 AU from the Sun. Beyond the edge is a sparse population of objects with large orbital eccentricities. Neptune shapes the dynamics of most Kuiper belt objects, but the recently discovered planet 2003 VB12 (Sedna) has an eccentric orbit with a perihelion distance of 70 AU, far beyond Neptune's gravitational influence....

... 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...

A study published in the journal Earth and Planetary Science Letters posits that Mars formed in what today is the Asteroid Belt, roughly one and a half times as far from the Sun as its current position, before migrating to its present location. The assumption has generally been that Mars formed near Earth from the same building blocks, but that conjecture raises a big question: why are the two planets so different in composition? Mars contains different, lighter, silicates than Earth, more akin to those found in meteorites. In an attempt to explain why the elements and isotopes on Mars...

Toronto– A close encounter with Jupiter about four billion years ago may have resulted in another planet’s ejection from the solar system altogether, scientists have found. The existence of a fifth giant gas planet at the time of the solar system’s formation — in addition to Jupiter, Saturn, Uranus and Neptune that we know of today — was first proposed in 2011, researchers said.

U.S. geochemists challenged commonly held theories about how gases are expelled from the Earth and how a planet's atmosphere is formed. Rensselaer Polytechnic Institute researchers said their new theory could change the way scientists view the timing and mechanism involved in the formation of Earth's atmosphere, as well as the atmospheres of Mars and Venus. The team, led by Professor E. Bruce Watson, said it has found substantial evidence that argon atoms are strongly bound in the minerals of Earth's mantle and move through those minerals at a much slower rate than previously thought. In fact, they said they discovered...