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Size comparison of Venus and Earth. Credit: NASA/JPL/Magellan Venus is only slightly smaller than the Earth, and so has enjoyed billions of years of a warm heart. But for this planet, sometimes called Earth's sister, that heat has betrayed it. That planet is now wrapped in suffocating layers of a poisonous atmosphere made of carbon dioxide and sulfuric acid. The pressures on the surface reach almost 100 times the air pressure at Earth's sea level. The average temperatures are more than 700°F, more than hot enough to melt lead, while the deepest valleys see records of more than 900°. If...

Using data that's three decades old, NASA scientists say they've figured out what happens to Venus' heat when it's lost to space — and discovered that the planet's surface may be "squishy" enough for it to be hemorrhaging its internal warmth...This Venusian discovery stems from astronomers trying to understand the planet's surface, which unlike Earth does not have tectonic plates to explain where its heat goes.

Jupiter’s gravity field varies with depth, which indicated that material is flowing as far down as 3,000 km (1,864 mi). Combined with information obtained during previous perijoves, this latest data suggests that Jupiter’s core is small and poorly defined. This flies in the face of previous models of Jupiter, which held that the outer layers are gaseous while the interior ones are made up of metallic hydrogen and a rocky core. ... Another interesting find was that Jupiter’s gravity field varies with depth, which indicated that material is flowing as far down as 3,000 km (1,864 mi). Combined with information...

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...

... 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...

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...

Radio, IR and optical observations show evolution of plumes and their impact on belts and zones Storm clouds rooted deep in Jupiter's atmosphere are affecting the planet's white zones and colorful belts, creating disturbances in their flow and even changing their color. Thanks to coordinated observations of the planet in January 2017 by six ground-based optical and radio telescopes and NASA's Hubble Space Telescope, a University of California, Berkeley, astronomer and her colleagues have been able to track the effects of these storms -- visible as bright plumes above the planet's ammonia ice clouds -- on the belts in which...

One of the big questions in solar physics is why the Sun's activity follows a regular cycle of 11 years. Researchers from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), an independent German research institute, now present new findings, indicating that the tidal forces of Venus, Earth and Jupiter influence the solar magnetic field, thus governing the solar cycle.

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...

Back in 2006, the Catalina Sky Survey in Arizona noticed that a mysterious body had begun orbiting the Earth. This object had a spectrum that was remarkably similar to the titanium white paint used on Saturn V rocket stages and, indeed, a number of rocket stages are known to orbit the Sun close to Earth. But this was not an object of ours. Instead, 2006 RH120, as it became known, turned out to be a tiny asteroid just a few metres across--a natural satellite like the Moon. It was captured by Earth's gravity in September 2006 and orbited us...

Scans from NASA’s Juno spacecraft have hinted that Jupiter’s core isn’t exactly what scientists once thought it was. The core isn’t as dense as researchers suspected, but determining why that is has proven to be a challenge. “This is puzzling,” Andrea Isella, co-author of a new study published in Nature, said in a statement. “It suggests that something happened that stirred up the core and that’s where the giant impact comes into play.”

Long before the Bible's tale of Jonah being swallowed by a whale, a small wannabe star has emerged intact after being engulfed by a neighboring giant star, scientists say. The victim was a brown dwarf, a failed star too small to sustain the nuclear reactions that ignites regular stars. The purpetrator was a red giant, an ancient star that once resembled our Sun but which puffed up to enormous size after its hydrogen fuel was depleted. The red giant has since expelled most of its gas into space and transformed into a dense, Earth-sized star called a white dwarfs. Using...

Meanwhile, the Doppler discovery of extrasolar planets orbiting very close to their parent stars has raised a different problem. Many of the planets are so close to their stars (<0.1 AU), and so hot, that they cannot be supposed to have formed where we now observe them. By inference, they could have formed at larger distances (several AU) and then migrated inwards. What would cause this inward migration? As with the solar system case, the root cause may be an exchange of angular momentum with material surrounding the planets at their formation. In particular, if the extrasolar planets formed in...

Russell Mapes, a graduate student from Grass Valley, Calif., ...explains that these sediments of eastern origin were washed down from a highland area that formed in the Cretaceous Period, between 65 million and 145 million years ago, when the South American and African tectonic plates separated and passed each other. That highland tilted the river's flow westward, sending sediment as old as 2 billion years toward the center of the continent. A relatively low ridge, called the Purus Arch, which still exists, rose in the middle of the continent, running north and south, dividing the Amazon's flow - eastward toward...

In his book "2061 - Odyssey Three" (the third of his Space Odyssey series), Arthur C. Clarke put forward the intriguing proposal that the core of the planet Jupiter was, in fact, a diamond the size of Earth. Now Clarke, even though a science fiction author of some repute, had a science background and always tried to bring rigorous scientific accuracy to his stories. So, could his proposition be possible? The somewhat predictable answer is - we don't know. But we can analyse the possibility within known scientific parametres, to see if it is, at least, possible. For diamond to...

Within the unimaginable depths of the universe there is a small family of worlds circling about a star we call the Sun; it is just a single star among the billions upon billions which are shining in the cosmos. Against the awesome backdrop of the infinite blackness of space, our world is just another planet; nothing more than an insignificant speck on the cosmological scale of things, but it is our home, and as of yet we have found no other planets which are remotely like Earth. The history of our world is a story which is still largely incomplete....