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This theory is a candidate for most major advance there has ever been in our understanding of human and solar system origins

Sent primarily to investigate the origin and evolution of Jupiter, Juno has been able to take in bonus observations of the planet's four major moons - Callisto, Ganymede, Europa and now Io. It performed its close flyby of Ganymede in 2021, and of Europa earlier this year. These passes produced some novel insights from Juno's microwave radiometer. Intended to look deep into the clouds of Jupiter, this instrument has also been able to see down through the ice layers of Ganymede and Europa for tens of kilometres. These two moons are of particular interest because they're both thought to hide...

20 Minute intro to the Ganymede Hypothesis Ganymede is Jupiter's largest moon. Just a bit smaller than Mars, it is an icy wasteland now but that appears not to have always been the case. There is reason to believe that a few tens of thousands of years ago, it would have been a warm, fresh-water ocean world with islands and floating bergs of pumice and luxuriant vegetation. There is a Youtube channel called Ganymede Hypothesius containing related materials.The unabridged version of the story is a free download in pdf format, around 340 pages. This theory is not exactly genesis but...

Explanation: Jupiter and its moons move like our Sun and its planets. Similarly, Jupiter spins while its moons circle around. Jupiter’s rotation can be observed by tracking circulating dark belts and light zones. The Great Red Spot, the largest storm known, rotates to become visible after about 15 seconds in the 48-second time lapse video. The video is a compilation of shorts taken over several nights last month and combined into a digital recreation of how 24-continuous hours would appear. Jupiter's brightest moons always orbit in the plane of the planet's rotation, even as Earth’s spin makes the whole system...

One of Jupiter's tenuous rings can be seen in this infrared image. (NASA/ESA/CSA/STScI/Judy Schmidt) Given its similarities to its neighbor, Saturn, it seems natural to ask why Jupiter doesn't also have a magnificent, extensive system of visible rings. Alas, it's not the reality. While Jupiter does have rings, they're thin, tenuous, flimsy things of dust, visible only when back-lit by the Sun. According to new research, these discount rings lack bling because Jupiter's posse of chonky Galilean moons keep discs of rock and dust from accumulating the way they do around Saturn. "It's long bothered me why Jupiter doesn't have...

For the first time, astronomers have uncovered evidence of water vapor in the atmosphere of Jupiter's moon Ganymede. This water vapor forms when ice from the moon's surface sublimates—that is, turns from solid to gas... ...Previous research has offered circumstantial evidence that Ganymede, the largest moon in the solar system, contains more water than all of Earth's oceans. However, temperatures there are so cold that water on the surface is frozen solid.... ...Roth and his team then took a closer look at the relative distribution of the aurora in the UV images. Ganymede's surface temperature varies strongly throughout the day,...

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...

The spacecraft flew closer to Jupiter’s largest moon than any other in more than two decades, offering dramatic glimpses of the icy orb. The first two images from NASA Juno’s June 7, 2021, flyby of Jupiter’s giant moon Ganymede have been received on Earth. The photos – one from the Jupiter orbiter’s JunoCam imager and the other from its Stellar Reference Unit star camera – show the surface in remarkable detail, including craters, clearly distinct dark and bright terrain, and long structural features possibly linked to tectonic faults.This image of Ganymede was obtained by the JunoCam imager during Juno’s June...

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...

NASA’s Galileo spacecraft surprised scientists when it revealed that Jupiter’s moon Ganymede generated its own magnetic field. But new research shows Ganymede also creates incredibly powerful waves that rocket particles to enormous energies. Scientists revealed these huge electromagnetic waves while studying old data from Galileo, which orbited Jupiter from 1995 to 2003. The observations show another wild way that a moon can interact with the magnetic field of its planet. Jupiter’s radius is around 11 times that of Earth, but it is perhaps 20,000 times more magnetic. This generates an intense radiation environment around the planet. Typically, these waves around...

Within the Jupiter system, there are 67 confirmed moons of varying size, shape and composition. In honor of Jupiter’s namesake, they are sometimes collectively referred to as the Jovians. Of these, the four largest – Io, Europa, Ganymede and Callisto – are known as the Galileans (in honor of their founder, Galileo Galilei). These four moons are among the largest in the Solar System, with Ganymede being the largest of them all, and even larger than the planet Mercury. In addition, three of these moons – Europa, Ganymede and Callisto – are all believed or known to have interior oceans...

Explanation: Some of the Solar System's largest moons rose together on February 23. On that night, a twilight pairing of a waning gibbous Moon and Jupiter was captured in this sharp telescopic field of view. The composite of short and long exposures reveals the familiar face of our fair planet's own large natural satellite, along with a line up of the ruling gas giant's four Galilean moons. Left to right, the tiny pinpricks of light are Callisto, Io, Ganymede, [Jupiter], and Europa. Closer and brighter, our own natural satellite appears to loom large. But Callisto, Io, and Ganymede are actually...

Explanation: On June 30, Venus and Jupiter were close in western skies at dusk. Near the culmination of this year's gorgeous conjunction, the two bright evening planets are captured in the same telescopic field of view in this image taken after sunset from Bejing, China. As the two bright planets set together in the west, a nearly Full Moon rose above the horizon to the south and east. Imaged that night with the same telescope and camera, the rising Moon from the opposite part of the sky is compared with the planetary conjunction for scale in the digitally composited image....

The dwarf planet Pluto and its system of five moons are about as mysterious as the underworld of antiquity that inspired their names. ... “We are still baffled by how the system formed,” says study co-author Mark Showalter, a senior research scientist at the Search for Extraterrestrial Intelligence (SETI) Institute. “I think everyone believes that, at some point in the distant past, a large object bashed into ‘proto-Pluto’ and the moons formed out of the debris cloud. However, after that point in the story, details get very sketchy.” Now, analysis of data collected from the Hubble Space Telescope following the...

Explanation: In this sharp snapshot, the Solar System's largest moon Ganymede poses next to Jupiter, the largest planet. Captured on March 10 with a small telescope from our fair planet Earth, the scene also includes Jupiter's Great Red Spot, the Solar System's largest storm. In fact, Ganymede is about 5,260 kilometers in diameter. That beats out all three of its other fellow Galilean satellites, along with Saturn's Moon Titan at 5,150 kilometers and Earth's own Moon at 3,480 kilometers. Though its been shrinking lately, the Great Red Spot's diameter is still around 16,500 kilometers. Jupiter, the Solar System's ruling gas...

Larger than the planet Mercury, Ganymede is one of four moons discovered by Galileo in 1610, easily visible in small telescope and large binoculars. The subsurface ocean confirmed by Hubble is believed to be at least 60 miles thick, containing more water than all of Earth's ocean's combined. As such, Ganymede joins a growing list of planets and moons in Earth's solar system, including Jupiter's moon Europa and Saturn's moon Enceladus, that are known to harbor vast reservoirs of liquid water. The latest findings using the Hubble Space Telescope build on earlier observations by NASA's Galileo spacecraft that showed Ganymede...

While this is merely a convenient illusion caused by the passage of Ganymede in front of Jupiter – something it does on a regular basis – the timing and appearance are perfect. The above image, however, was captured by the Hubble Space Telescope on April 21st, 2014, when kids were perhaps thinking of the Easter Bunny, not monsters and goblins. At the time, Hubble was being used to monitor changes in Jupiter’s immense Great Red Spot (GRS) storm. During the exposures, the shadow of the Jovian moon Ganymede swept across the center of the GRS, giving the giant planet the...

Explanation: For astrobiologists, these may be the four most tantalizing moons in our Solar System. Shown at the same scale, their exploration by interplanetary spacecraft has launched the idea that moons, not just planets, could have environments supporting life. The Galileo mission to Jupiter discovered Europa's global subsurface ocean of liquid water and indications of Ganymede's interior seas. At Saturn, the Cassini probe detected erupting fountains of water ice from Enceladus indicating warmer subsurface water on even that small moon, while finding surface lakes of frigid but still liquid hydrocarbons beneath the dense atmosphere of large moon Titan. Now looking...

Scientists have created the first global geological map of Jupiter's huge, ice-covered moon Ganymede, more than 400 years after its discovery by Galileo Galilei. The map, created using observations by NASA's twin Voyager probes and Galileo orbiter, highlights the varied terrain of Ganymede, which is bigger than the planet Mercury. "This map illustrates the incredible variety of geological features on Ganymede and helps to make order from the apparent chaos of its complex surface," Robert Pappalardo, of NASA's Jet Propulsion Laboratory in Pasadena, Calif., said in a statement. "This map is helping planetary scientists to decipher the evolution of this...

Compared to other animals, humans have very little genetic diversity, e.g. http://humanorigins.si.edu/evidence/genetics/skin-color/modern-human-diversity-genetics People today look remarkably diverse on the outside. But how much of this diversity is genetically encoded? How deep are these differences between human groups? First, compared with many other mammalian species, humans are genetically far less diverse – a counterintuitive finding, given our large population and worldwide distribution. For example, the subspecies of the chimpanzee that lives just in central Africa, Pan troglodytes troglodytes, has higher levels of diversity than do humans globally, and the genetic differentiation between the western (P. t. verus) and central (P. t....