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Io boasts more than 130 active volcanoes with an estimated 400 total, making it the most volcanically active place in the Solar System. Juno used its Jovian Infrared Aurora Mapper (JIRAM) to take spectacular photographs of Io during Perijove 7 last July... Juno’s Io looks like it’s on fire. Because JIRAM sees in infrared, a form of light we sense as heat, it picked up the signatures of at least 60 hot spots on the little moon on both the sunlight side (right) and the shadowed half. Like all missions to the planets, Juno’s cameras take pictures in black and...

March 2018 was the least active month for sunspots since the middle of 2009, almost nine years ago. In fact, activity in the past few months has been so low it matches the low activity seen in late 2007 and early 2008, ten years ago when the last solar minimum began

A supernova is one of the most impressive natural phenomena in the Universe. Unfortunately, such events are often brief and transient, temporarily becoming as bright as an entire galaxy and then fading away. But given what these bright explosions – which occur when a star reaches the end of its life cycle – can teach us about the Universe, scientists are naturally very interested in studying them. Using data from the Dark Energy Survey Supernova (DES-SN) program, a team of astronomers recently detected 72 supernovae, the largest number of events discovered to date. These supernovae were not only very bright,...

A massive "hole" on the surface of the sun has unleashed a strong solar wind that scientists say may amp up the northern lights in some areas of the U.S. and could disrupt satellite communications over the next few days. Data from NASA's Solar Dynamics Observatory revealed a vast region where the sun's magnetic field has opened up, creating a gap in the sun's outer atmosphere, called the corona. This region, also known as a coronal hole, allows charged particles to escape and flow toward Earth in an increased solar wind. As a result, the U.S. Space Weather Prediction Center...

Known as Transient Luminous Events (TLEs), these unusual features were first spotted by accident in 1989. Minnesota professor John R Winckler was testing a television camera in advance of an upcoming rocket launch, when he realised that two frames showed bright columns of light above a distant storm cloud. The discovery came as a shock to scientists at the time, according to Dr Torsten Neubert, ASIM's lead scientist. "That really surprised all of us. How come this exists and we didn't know it? Airline pilots must have known about it - there are some anecdotal descriptions," the Technical University of...

"...On Earth quartz veins indicate past water flow, and also indicate the presence of valuable minerals like gold. What these veins on Mars mean is presently unknown, though I guarantee the Curiosity science team is using the rover to find out everything they can. Almost certainly the veins suggest the past presence of liquid flows, probably water (but I make no promises)."

"Time for some more weird Mars geology! Today the science team for the high resolution camera on Mars Reconnaissance Orbiter released its monthly batch of new images. There is a lot of interesting stuff buried therein...."

"One of the prime areas of research for Mars planetary geologists is the region on Mars where the geography appears to transition from the southern cratered, rough terrain to the northern low, generally smooth, and flat plains. It is theorized by some scientists that the northern plains were once an ocean, probably shallow and probably intermittent, but wet nonetheless for considerable periods..."

Billions of years ago... our planet’s primordial atmosphere was toxic to life as we know it, consisting of carbon dioxide, nitrogen and other gases. However, by the Paleoproterozoic Era (2.5–1.6 billion years ago), a dramatic change occurred where oxygen began to be introduced to the atmosphere – known as the Great Oxidation Event (GOE). [S]cientists were not sure if this event – which was the result of photosynthetic bacteria altering the atmosphere – occurred rapidly or not. ... Based on newly-discovered geological evidence, the team concluded that the introduction of oxygen to our atmosphere was “more like a fire hose”...

Once upon a time there was a massive flood across the Mediterranean Sea, an in-pouring of water so huge that it excavated a canyon five kilometres deep and 20 kilometres long, and created a waterfall with a 1.5 kilometre drop. Evidence for the great flood, long hypothesised, has now been found by a team of researchers led by geoscientist Aaron Micallef from the University of Malta. And while several Mediterranean traditions feature great flood narratives, the earliest arising from Sumeria and already well enough known to be recorded in cuneiform by the seventeenth century BCE, this one is unlikely to...

Our solar system's first known interstellar visitor is likely even more alien than previously imagined, a new study suggests. The mysterious, needle-shaped object 'Oumuamua, which was spotted zooming through Earth's neighborhood last October, probably originated in a two-star system, according to the study. 'Oumuamua means "scout" in Hawaiian; the object was discovered by researchers using the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), at Haleakala Observatory on the island of Maui. ... "It's really odd that the first object we would see from outside our system would be an asteroid, because a comet would be a lot easier to...

Sumerians settled in Mesopotamia, an area of modern Iraq known as the cradle of civilization, more than 6,000 years ago, where they invented writing, the wheel, the plough, irrigation, the 24-hour day and the first city-states. Mission co-leaders Licia Romano and Franco D'Agostino of Rome's Sapienza University said Tuesday they discovered one of their ancient ports in Abu Tbeirah, a desert site about 7 kilometers (4.3 miles) south of the town of Nasiriyah. The port's basin, measuring 130 meters (142 yards) in length and 40 meters (44 yards) wide, with a capacity equal to nine Olympics-sized pools, may have also...

Scholz's star -- named after the German astronomer who discovered it -- approached less than a light-year from the Sun. Nowadays it is almost 20 light-years away, but 70,000 years ago it entered the Oort cloud, a reservoir of trans-Neptunian objects located at the confines of the solar system. ... Now two astronomers from the Complutense University of Madrid, the brothers Carlos and Raúl de la Fuente Marcos, together with the researcher Sverre J. Aarseth of the University of Cambridge (United Kingdom), have analyzed for the first time the nearly 340 objects of the solar system with hyperbolic orbits (very...

A new scenario seeking to explain how Mars’ putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million years earlier and were not as deep as once thought. The early ocean known as Arabia (left, blue) would have looked like this when it formed 4 billion years ago on Mars, while the Deuteronilus ocean, about 3.6 billion years old, had a smaller shoreline. Both coexisted with the massive volcanic province Tharsis, located on the unseen side of the planet, which may have helped support the existence of liquid water. The water...

In such a scenario, scientists expect that about a fifth of the Moon's material would have come from Earth and the rest from the impacting body. The Moon, our planet's constant companion for some 4.5 billion years, may have been forged by a rash of smaller bodies smashing into an embryonic Earth, researchers have revealed. A bombardment birth would explain a major inconsistency in the prevailing hypothesis that the Moon splintered off in a single, giant impact between Earth and a Mars-sized celestial body. In such a scenario, scientists expect that about a fifth of the Moon's material would have...

Image: NASA’s Goddard Space Flight Center The moon is under constant bombardment by meteorites and asteroids that can leave massive craters on its surface. The Aitken basin, the largest impact crater on the lunar surface, has a diameter equivalent to the distance from London to Athens, Greece. But not all craters are so noticeable — most are relatively insignificant. Thousands of previously unknown craters have been spotted on the moon thanks to an artificial intelligence program designed by researchers at the University of Toronto. “We created an A.I. powered method that autocratically identifies craters on the surface of the moon,...

A team of researchers from around the world, working as part of the Corinth Active Rift Development expedition, collected 1.6 kilometers (one mile) of sediment core and data from boreholes at three different locations in the Gulf of Corinth in Central Greece. The samples provide a continuous, high resolution record of complex changes in past environment and rift-faulting rates over at least the last one million years. The Corinth Rift is one of the most seismically active areas in Europe where one of the Earth's tectonic plates is being ripped apart causing geological hazards including earthquakes, tsunamis and landslides... The...

Bennu has a shape that looks a bit like a spinning top. It is roughly 500 meters (1,640 feet) in diameter and orbits the sun once every 1.2 years, or 436.604 days. Every six years or so, it comes very close to Earth — about 0.002 AU, according to the University of Arizona. (... well within the orbit of Earth's moon.) Bennu is part of a small class of carbonaceous (dark) asteroids that likely have primitive materials in them. Called a B-type class, Bennu and other asteroids like it have materials such as volatiles (compounds with a low boiling point),...

The faces of disaster through the ages are legion, and the dusty places of archaeological digs in Israel have been no exception, as archaeologists at the Tel Gezer excavation site in central Israel will tell you after they encountered 3,200-year-old skeletal remains of three individuals. As they were conducting excavations during the summer of 2017, traces of human bones emerged as they dug within a stratum that evidenced a fiery destruction. They were articulated skeletons. The archaeologists could see that one of them, an adult, whose remains were badly decomposed and burned, was lying with hands over the head. The...

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...