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The planet Uranus and its five biggest moons may not be the dead sterile worlds that scientists have long thought. Instead, they may have oceans, and the moons may even be capable of supporting life, scientists say. Much of what we know about them was gathered by Nasa’s Voyager 2 spacecraft... flew past and sent back sensational pictures of the planet and its five major moons. But what amazed scientists even more was the data Voyager 2 sent back indicating that the Uranian system was even weirder than they thought. The measurements from the spacecraft’s instruments indicated that the planets...

a grey, lumpy moon in front of the red surface of Mars Credit: Emirates Mars Mission The United Arab Emirates Space Agency (UAESA) has just produced the best images ever taken of Mars’ moon Deimos — and they suggest the tiny satellite isn’t what we thought it was. Mars’ moons: Mars has two moons. The larger of them, Phobos, is 14 miles wide and orbits the planet from a distance of just 3,700 miles, while the smaller one, Deimos, is only 9 miles in diameter and circles it from 14,580 miles away. “We expect to … advance our fundamental understanding...

With the confirmation of a dozen new moons in Jupiter’s orbit, the biggest planet in the Solar System is suddenly the neighborhood big dog when it comes to moon collection. With the advent of these 12 previously undiscovered moons, the gas giant now has 92 known orbiting entities, surpassing Saturn’s amazing collection of 83. Although scientists face a significant challenge in locating these tiny celestial entities, both planets are really expected to be joined by many more moons. The intense glare emitted by Jupiter further complicates things, and any that are tiny enough to have escaped discovery up to now...

Explanation: This moon is doomed. Mars, the red planet named for the Roman god of war, has two tiny moons, Phobos and Deimos, whose names are derived from the Greek for Fear and Panic. These martian moons may well be captured asteroids originating in the main asteroid belt between Mars and Jupiter or perhaps from even more distant reaches of our Solar System. The larger moon, Phobos, is indeed seen to be a cratered, asteroid-like object in this stunning color image from the robotic Mars Reconnaissance Orbiter, with objects as small as 10 meters visible. But Phobos orbits so close...

Eliminate the impossible, as Sherlock Holmes once said, and the truth, no matter how improbable, lies in whatever remains. Good advice for detectives — and, it turns out, for astronomers. Astronomy is often little more than piecing together scattered clues, carefully eliminating possibilities and arriving at an improbable truth. Take, for example, the announcement of an exomoon discovery back in 2017. Observations seemed to show the presence of large moon, one as big as Neptune, orbiting a gas giant in a distant solar system. But, as the authors of the announcement were careful to state, the discovery was far from...

Elektra and its three moons. (ESO/Berdeu et al., Yang et al.) ====================================================================================== An asteroid discovered in the 19th century has just been identified as the most crowded we've ever found. It's called 130 Elektra, or just Elektra for short, and astronomers have just discovered that it has not one, nor two, but three smaller satellite companions, or moons. That not only makes it the most numerous asteroid system known to date, but demonstrates how we might find other faint, hard-to-see asteroid moons in the future. "Elektra is the first quadruple system ever detected," wrote a team of astronomers led by...

Explanation: What's that moving across the sky? A planet just a bit too faint to see with the unaided eye: Uranus. The gas giant out past Saturn was tracked earlier this month near opposition -- when it was closest to Earth and at its brightest. The featured video captured by the Bayfordbury Observatory in Hertfordshire, UK is a four-hour time-lapse showing Uranus with its four largest moons in tow: Titania, Oberon, Umbriel and Ariel. Uranus' apparent motion past background stars is really dominated by Earth's own orbital motion around our Sun. The cross seen centered on Uranus is called a...

Grey, heavily cratered, and peering out from the black of space, Ganymede looks a lot like our moon. But the icy rock is more than 650 million kilometers (400 million miles) away – it's the largest moon in the Solar System, and it circles Jupiter. NASA's Juno spacecraft has been rocketing around Jupiter since 2016, but on Monday, it zipped past Ganymede, coming within 1,000 km (650 miles) of the moon. No spacecraft had gotten that close in more than two decades – the last approach was NASA's Galileo spacecraft in 2000. In just 25 minutes, Ganymede went from being...

Uranus, far from Earth in the darker region of the Solar System's planetary reach, isn't alone. It's accompanied by a retinue of moons - 27, to be precise. Far and dim, these moons are difficult to study, but astronomers have made an accidental discovery while observing Uranus. According to infrared images of the five main moons of Uranus, their composition is closer to that of dwarf planets like Pluto and Haumea - compact, rocky objects with an icy crust - than the more fluffy composition of the smaller Uranian moons. Uranus orbits the Sun at an average distance around 20...

The researchers suggest that this type of world may a result of large “hot Jupiter” exoplanets migrating toward their host star. Exoplanet surveys have detected several such planets, and it’s believed that they likely formed at a greater distance from their respective stars and then slowly crept inward. When that happens, it’s possible that the change in gravitational forces would prompt large moons to break free from their existing orbits and become standalone worlds of their own. Computer simulations showed that this could indeed happen, and in those cases, the researchers believe we should call them ploonets. Remarkably, our own...

NASA has a message for space lovers this month: Look up. The largest planet in the solar system, Jupiter, will be clearly visible June 10 — and to see its biggest moons you'll only need to grab a pair of binoculars. NASA said the gas giant is at its "biggest and brightest this month" and will be visible all night. The planet will reach opposition, the annual occurrence when the Jupiter, Earth and the Sun are arranged in a straight line, with Earth in the center. So, mark your calendars for Monday, as it will be the best time of...

Just because Jupiter's moon Europa is coated in ice doesn't mean all that ice is the same temperature. And now, scientists have mapped the hot and cold spots on the moon's surface using data gathered from Earth, with accuracy down to 125 miles (200 kilometers). While most of the temperature variations they measured can be explained by sunlight's influence on the ice, there's one unusually cold spot that is stumping the scientists behind the new research. That spot, which falls on the moon's northern hemisphere, stood out in images taken at different times of the day, which surprised the scientists....

The larger planets such as Saturn, Jupiter and Uranus remarkably put off more energy than they absorb from our sun. If they were actually in the billions of years of age, should they not have become frozen and expired an incalculable length of time ago. Scientists in this field have come up with many reasons as to the how that these celestial entities kept their heat as far as their theories; however, their noses are firmly planted in a major wall that repels everything they've come up with. Volcanism observed on Jupiter's Io and the geyers with Saturn's Enceladus command...

In March 2017, Jupiter was in the perfect location to be observed using the Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile, which has the Dark Energy Camera and can survey the sky for faint objects. Astronomer Scott Sheppard of the Carnegie Institution for Science and his team were using the telescope to search the edge of the solar system for signs of Planet Nine. They realized they could observe Jupiter at the same time. They would be able to tell the difference between Jupiter and the objects around it versus the distant solar system objects because any...

Radar images obtained between August 29 and September 1, when Florence came closest to Earth, reveal that the asteroid is about 2.8 miles (4.5 kilometers) in size, the US space agency said. It said the two moons were probably between 300-1,000 feet (100-300 meters) across. The inner moon takes approximately eight hours to revolve around Florence while the outer moon takes between 22 and 27 hours, NASA said. NASA said the radar images of Florence, which was discovered in 1981, were obtained by the Goldstone Deep Space Communications Complex in California.

Enceladus’ south pole is wounded, bleeding heat and water. Its injury may have come from a huge rock smashing into this frigid moon of Saturn less than 100 million years ago, leaving the area riddled with leaky cracks. The region near Enceladus’ south pole marks one of the solar system’s most intriguing mysteries. It spews plumes of liquid from an interior ocean, plus an enormous amount of heat. The south pole’s heat emission is about 10 gigawatts higher than expected – equivalent to the power of 4000 wind turbines running at full capacity. The rest of the moon, though, is...

Did a giant impact create the two faces of Mars? 16:29 15 March 2007 NewScientist.com news service David Shiga, Houston Mars's northern hemisphere is lower in elevation – by about 5 kilometres – than its southern hemisphere (see image below). This coloured topographical map shows low elevations in blue and high elevations in yellow and red. The map is centred on a latitude of 55° north (Illustration: Mike Caplinger/MSSS) Mars's southern hemisphere is higher and more heavily cratered than the northern hemisphere, suggesting it is older terrain. The two low elevations (blue) in this map, which is centred on the...

A volcano on Mars half the size of France spewed so much lava 3.5 billion years ago that the weight displaced the Red Planet's outer layers, according to a study released Wednesday. Mars' original north and south poles, in other words, are no longer where they once were. The findings explain the unexpected location of dry river beds and underground reservoirs of water ice, as well as other Martian mysteries that have long perplexed scientists, the lead researcher told AFP. "If a similar shift happened on Earth, Paris would be in the Polar Circle," said Sylvain Bouley, a geomorphologist at...

Jafar Arkani-Hamed of McGill University discovered that five impact basins--dubbed Argyre, Hellas, Isidis, Thaumasia and Utopia--form an arclike pattern on the Martian surface. Three of the basins are well-preserved and remain visible today. The locations of the other two, in contrast, were inferred from measurements of anomalies in the planet's gravitational field... a single source--most likely an asteroid that was initially circling the sun in the same plane as Mars--created all five craters. At one point the asteroid passed close to the Red Planet... and was broken apart by the force of the planet's gravity. The resulting five pieces subsequently...

New Theory: Catastrophe Created Mars' Moons By Leonard David Senior Space Writer posted: 07:00 am ET 29 July 2003 PASADENA, California – The two moons of Mars – Phobos and Deimos – could be the byproducts of a breakup of a huge moon that once circled the red planet, according to a new theory. The capture of a large Martian satellite may have taken place during or shortly after the formation of the planet, with Phobos and Deimos now the surviving remnants. Origin of the two moons presents a longstanding puzzle to which one researcher proposed the new solution at...