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More clues about where to search for a possible ninth planet lurking in the fringes of our solar system are emerging from the Kuiper belt, the icy debris field beyond Neptune. And new calculations suggest that the putative planet might be brighter — and a bit easier to find — than once thought. Evidence for the existence of Planet Nine is scant, based on apparent alignments among the orbits of the six most distant denizens of the Kuiper belt (SN: 2/20/16, p. 6). Their oval orbits all point in roughly the same direction and lie in about the same plane,...

There may be an alien planet lurking within Earth's own solar system. If the hypothetical Planet Nine does indeed exist, the sun probably ripped the world away from another star long ago, a new study suggests. "It is almost ironic that while astronomers often find exoplanets hundreds of light-years away in other solar systems, there's probably one hiding in our own backyard," study lead author Alexander Mustill, an astronomer at Lund University in Sweden, said in a statement. [The Evidence for Planet Nine in Pictures]. Earlier this year, astronomers Konstantin Batygin and Mike Brown, both of the California Institute of...

A mysterious planet that wiped out life on Earth millions of years ago could do it again, according to a top space scientist. And some believe the apocalyptic event could happen as early as this month. Planet Nine — a new planet discovered at the edge of the solar system in January — has triggered comet showers that bomb the Earth’s surface, killing all life, says Daniel Whitmire, of the University of Louisiana. The astrophysicist says the planet has a 20,000-year orbit around the sun and, at its closest to us, it knocks asteroids and comets toward Earth. Fossil evidence...

http://www.thescottishsun.co.uk/scotsol/homepage/7054203/Mysterious-planet-wiped-out-life-on-Earth-once-and-could-do-it-again-THIS-MONTH.html?redirect=true

Periodic mass extinctions on Earth, as indicated in the global fossil record, could be linked to a suspected ninth planet, according to research published by a faculty member of the University of Arkansas Department of Mathematical Sciences. Daniel Whitmire, a retired professor of astrophysics now working as a math instructor, published findings in the January issue of Monthly Notices of the Royal Astronomical Society that the as yet undiscovered "Planet X" triggers comet showers linked to mass extinctions on Earth at intervals of approximately 27 million years. Though scientists have been looking for Planet X for 100 years, the possibility...

And this new planet could be huge. Back in January, the astronomer who led the charge to have Pluto demoted to dwarf planet status announced that he’d just found evidence that a huge, icy planet could be lurking on the edge of the Solar System, just past Neptune. Mike Brown, a planetary astronomer at Caltech University, estimated that the hypothetical 'Planet Nine' appears to be circling the Sun on a super-elongated orbit that takes an incredible 10,000 to 20,000 years to complete. And now, thanks to a newly detected Kuiper Belt Object (KBO) that’s acting really strange, Brown says the...

Based on a careful study of Saturn's orbit and using mathematical models, French scientists were able to whittle down the search region for Planet Nine to "possible" and "probable" zones. Source: CNRS, Cote d'Azur and Paris observatories. Created by the author Astronomy, Cassini, Planet News, Solar SystemSearch Narrows For Planet Nine 25 Feb , 2016 by Bob King An imagined view from Planet Nine looking back toward the Sun. Astronomers think the massive, distant planet is gaseous, similar to the other giant planets in our Solar System. Credit: Wikipedia Last month, planetary scientists Mike Brown and Konstantin Batygin of...

Planet Nine - a newly proposed but not yet confirmed world perhaps 10 times more massive than Earth that's thought to orbit far beyond Pluto — probably could not have triggered such "death from the skies" events, researchers said. Planet Nine likely has an elliptical orbit, coming within 200 to 300 astronomical units (AU) of the sun at its closest approach and getting as far away as 600 to 1,200 AU, Brown said. (One AU is the distance from Earth to the sun - about 93 million miles, or 150 million kilometers). Neptune orbits about 30 AU from the sun,...

It’s a big, dark presence at the farthest reaches of our solar system, a mysterious force powerful enough to skew the paths of planets in orbit and yet so subtle that it slips undetected past even the most powerful telescopes on Earth. For centuries, it has eluded some of the most brilliant minds in astronomy — some say it even destroyed one. It’s the subject of endless calculations and rampant speculation, crackpot theories and countless hours spent gazing, fruitlessly, at the night sky. It’s known as Planet X. And on Tuesday, a group of astronomers said they’d found not just...

One thing we know for sure is that conditions on Earth were, shall we say, unpleasant for the dinosaurs at the moment of their demise. Alternate and overlapping theories suggest the great beasts were pelted with monster comets, drowned by mega-tsunamis, scorched with lava, starved by a landscape stripped of vegetation, blasted with the radiation of a dying supernova, cloaked in decades of darkness, and frozen in an ice age. Now, a pair of researchers have new evidence to support a link between cyclical comet showers and mass extinctions, including the one that they believe wiped out the dinosaurs 66...

136108 Haumea — one of the strangest worlds of them all — was introduced into the solar system menagerie about ten years ago. Discovered by Mike Brown (@Plutokiller extraordinaire) and team in late December 2004 from the Palomar Observatory, Haumea (say HOW-meh) received its formal name on September 17, 2008 along with its dwarf planet designation. Haumea is a fast rotator, with a ‘day’ equal to about four hours. We know this due to periodic changes in brightness. Haumea also has a high albedo of about 80%, similar to freshly fallen snow. Models suggest that Haumea is about twice as...

Presently, our solar system is known to contain 4 fully-fledged rocky worlds: Mercury, Venus, Earth and Mars; 2 ice-giants: Neptune and Uranus; 2 gas-giants, Saturn and Neptune; 5 dwarf-planets, Ceres. Pluto, Eris, MakeMake, Haumea; around 100 moons; and an unknowable number of comets, asteroids and minor planets. Indeed, we’ve only begun to understand the full scope of our local corner of our galaxy, and new information emerges on a monthly-basis, yet there a number of seemingly obvious things that remain unknown. For instance, long before Pluto’s existence was deduced, astronomers scoured the outer solar system in search of another large...

In their studies, the team analyzed the effects of what is called the ‘Kozai mechanism,’ which is related to the gravitational perturbation that a large body exerts on the orbit of another much smaller and further away object. They looked at how the highly eccentric comet 96P/Machholz1 is influenced by Jupiter (it will come near the orbit of Mercury in 2017, but it travels as much as 6 AU at aphelion) and it may “provide the key to explain the puzzling clustering of orbits around argument of perihelion close to 0° recently found for the population of ETNOs,” the team...

There’s something odd floating around in the outer solar system. Actually, there’s lots of odd things floating around in the outer solar system, but 2002 UX25 is one of the most baffling. The mid-sized Kuiper belt object (KBO) measures 650 kilometers (400 miles) across, and yet it has a density less than water (less than 1 gram per cubic centimeter). Yes, if you put it in a huge bathtub, 2002 UX25 would float. ...planetary scientist Mike Brown, of the California Institute of Technology (Caltech) in Pasadena, has taken a measure of 2002 UX25′s density and discovered that it is “the...

Many galaxies appear to have stronger gravity - and thus more mass - than can be explained by their visible matter alone. Overly massive galaxies are most often attributed to dark matter, an invisible substance that interacts with matter through gravity. To date, though, no one has directly detected dark matter particles. But a well-established notion in physics could hold another explanation for their size. This says that empty space is really a frothy, turbulent sea full of virtual particles - matter and antimatter that spring in and out of existence so fast that we can't see them. Though they...

Small objects could be rounded worlds, based on likely sizes, experts say. Three relatively bright space rocks recently found in Pluto's neighborhood may be new members of the dwarf planet family, astronomers say. The objects were discovered in a little studied section of the Kuiper belt, a region of the solar system that starts beyond the orbit of Neptune and extends 5.1 billion miles (8.2 billion kilometers) from the sun. Astronomer Scott Sheppard, of the Carnegie Institute of Washington, and colleagues found the bodies using the 1.3-meter Warsaw University Telescope at Las Campanas in Chile. The region of the Kuiper...

Nasa scientists are searching for an invisible 'Death Star' that circles the Sun, which catapults potentially catastrophic comets at the Earth. The star, also known as Nemesis, is five times the size of Jupiter and could be to blame for the impact that wiped out the dinosaurs 65 million years ago. The bombardment of icy missiles is being blamed by some scientists for mass extinctions of life that they say happen every 26 million years Nemesis is predicted to lie at a distance equal to 25,000 times that of the Earth from the Sun, or a third of a light-year....

A distant, icy rock whose discovery shook up the solar system and led to Pluto's planetary demise has been given a name: Eris. The christening of Eris, named after the Greek goddess of chaos and strife, was announced by the International Astronomical Union on Wednesday. Weeks earlier, the professional astronomers' group stripped Pluto of its planethood under new controversial guidelines. Since its discovery last year, Eris, which had been known as 2003 UB313, ignited a debate about what constitutes a planet. Astronomers were split over how to classify the object because there was no universal definition. Some argued it should...

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....

When is a planet not a planet? That is what astronomers will be asking themselves after yesterday's announcement of the biggest planetary body discovered in the solar system in more than 70 years. The new body, called Quaoar (pronounced Kwah-o-ar), is a round world that orbits the sun every 288 years, at a distance greater than that of any of the nine planets. At 1250 kilometres wide, it is bigger than any of the asteroids. In fact, it is bigger than all the asteroids put together. But it is also just over half the size of the smallest planet in...