New Solar System Models Show Earth Is No Fluke
Astrobiologists use new starting points to produce ‘organic’ models of our solar system’s formation.
The study of planets and moons
Astrobiologists use new starting points to produce ‘organic’ models of our solar system’s formation.
Something's wetting the surface of dwarf planet Pluto along the northern edge of Sputnik Planitia, and planetary scientists have found a good explanation for it. A recent study of new Horizons images taken during the 2015 flyby revealed evidence that liquid nitrogen is rising up through cracks in Sputnik Planitia. That's the giant heart-shaped glacial basin we see in all the Pluto images taken by the spacecraft.
Of Jupiter’s four Galilean moons, Callisto is the one that gets the least attention. Io is constantly being resurfaced by volcanoes. Europa has a giant liquid water ocean. And Ganymede has its own magnetic field that interacts with its parent planet in weird ways. Callisto, by comparison, seems sedate, with its ancient, crater-saturated surface seemingly frozen in time. But new data from the James Webb Space Telescope (JWST) shows that even this most benign of the Big Four moons is more active than previously realized.
The surface of Mars is home to some of the most breathtaking and awe-inspiring landscapes in the solar system. This is primarily due to the Red Planet lacking several re-surfacing processes that Earth possesses, including plate tectonics, volcanism, and flowing water. While Mars does have dust storms, this has done little to reshape the planet’s surface, which has remained largely undisturbed for billions of years. However, this near-pristine landscape has enabled scientists to look back in time while slowly piecing together what Mars was like long ago.
Science seems like a straightforward endeavour. You come up with a hypothesis, collect data to prove or disprove it, and analyze that data to see if the hypothesis is right. But anyone who actually does science will tell you many times it’s not that straightforward. And one of the most common complexities is in data analysis. A new paper suggests that one such complexity, known as regression to the mean, might be causing us to massively underestimate how severe solar storms can truly be.
Planet building was supposed to be one of the universe's slow projects, something that only got going billions of years after the Big Bang. New research suggests otherwise. The raw materials for rocky worlds, and perhaps even the water needed for life, may have been ready to go just 100 million years after the Big Bang, long before the first galaxies had even taken shape.
The atmospheric is a dynamic place, and just how well we understand that dynamism depends on what part of the atmosphere it is. Low altitudes can be reached by traditional balloons, with full suites of sensing equipment. Higher reaches are the domain of satellites, with their zippy orbits allowing them to travel through the less dense regions. But there a section scientists call the “ignorosphere”, between 30-100 kilometers up that still plays a major role in global climate dynamics, but which are only able to reach with temporary sounding rockets that only collect data for a few minutes before falling back to Earth. But a new technology from Benjamin Schafer of Rarefied Technologies that received a NASA Innovative Advanced Concepts (NIAC) grant hopes to solve that problem by inserting a fleet of sensors that can float in that area for months, while providing insight to these hard-to-capture long-term patterns that influence weather everywhere on the globe.
The surface of the Moon is a bleak and forbidding place that might be hiding a lot of water ice on and under the dusty landscape. However, most possible ice deposits don't just stand out in an image. You need specialized mapping to find traces of water ice. So, scientists have devised another way to find the Moon's frosty hidden reserves. They use seismic waves from moonquakes as locator beacons.
A snowflake cannot form out of nothing. Water vapour will sit in the air quite happily, supercooled and reluctant, until it finds a speck of dust to build on and then it crystallises around it. Cosmochemists have had a version of that problem for decades. The early Solar System was a furnace of gas, and the first solid grains had to condense out of it somehow, yet condensing from a perfectly uniform gas is slow and difficult work. New research from Caltech, analysing fragments of a meteorite that fell over Mexico in 1969, suggests the seeds were already there. Buried inside the oldest solids we possess are specks of stardust from a star that lived and died before the Sun existed.
Mars has plenty of water, and almost all of it is in the wrong place. The poles are rich in ice, the equator, where you would actually want to land, has none within reach. That leaves the mid-latitudes, and until now the honest answer about what lies beneath them has been a bit of a shrug. Two new studies from the Planetary Science Institute have changed the shape of that answer. Rather than simply asking whether the data are consistent with buried ice, they have started calculating the odds and can now say, of a given patch of Martian ground, that there is a 64 per cent chance of finding ice if you dig there.
As dwarf planet Pluto moves along in its distant, high-obliquity 248-year orbit, its atmosphere is changing. That's because it's beginning to travel through colder, darker parts of the outer Solar System for the next 88 years. As a consequence, the mostly-nitrogen atmosphere is expected to grow gradually thinner and eventually freeze out over the coming decades. When that happens, the atmosphere will shrink.
Simulations conducted by researchers at ETH Zurich suggest a strong likelihood that Venus’s rift valleys are still geologically active rather than being mere relics of a bygone era, as had been previously believed. This finding reshapes our understanding of Earth’s sister planet and will influence future missions to Venus.
Rover data from more than 20 years ago has revealed clues to the existence of liquid water on ancient Mars. The NASA Spirit Rover carried a specialized instrument called a Mössbauer Spectrometer that performed mineralogical analyses of soil, rock, and dust on the surface of the Red Planet at Gusev Crater. Individual measurements didn't always indicate definitive proof of water, but when scientist Paolo de Souza of Edith Cowan University in Australia examined years' worth of measurements together, a definite pattern began to show up in the existence of minerals that could only exist in the presence of water. His analysis shows that Mars used to sport a lot more water than scientists expected and that the data showing its existence was in the data all along.
We have been watching asteroid (44) Nysa for well over a century without ever really knowing what it looks like. Now the sharpest images ever taken of it, from two of the largest telescopes on Earth, have revealed two deep valleys running right around its circumference and the team behind them think those are necks, joining three separate lobes into a single 75 kilometre body. If that holds up, Nysa is the first three lobed world we have ever found. And in the glare beside it the same observations turned up something nobody was looking for, a tiny moon a kilometre across, which may be the thing that settles the argument.
The planet Neptune has 16 known moons, with its largest Moon, Triton, comprising more than 99.5 percent of the mass of all of them. Triton’s incredible size has led scientists to hypothesize it was a captured object originating from the Kuiper Belt, which wreaked havoc on Neptune’s original moon system upon its capture and subsequential elliptical orbit. Today, some remnants of these original moons are part of the dusty rings that orbit Neptune. But what did that original moon system consist of? Were they the same small worlds observed today or are they pieces of what was once much larger worlds?
Pluto’s moon, Charon, is one of the most unexplored (and arguably underappreciated) planetary objects in the entire solar system. This is primarily because it’s only been visited once by NASA’s New Horizons spacecraft during its famous Pluto flyby in July 2015. Despite this quick encounter, New Horizons beamed back troves of data regarding Charon that scientists continue to pour over with the goal of gaining insight into Charon’s formation and evolution. This is because Charon is the largest moon compared to its parent body in the solar system, noted by it being half of Pluto’s diameter and one-eighth of Pluto’s mass.
Cassini, NASA’s last major mission to Saturn, famously plunged to its fiery death in the gas giant’s atmosphere at the end of its mission. It had captured more accurate in-situ data of the Saturnian system than any mission before or since. But there’s one particular part that it couldn’t directly approach - Saturn’s rings. But NASA very obviously wants to take a nice up-close look at them, as they have recently funded a NASA Innovative Advanced Concepts (NIAC) Phase I grant to send a swarm of 10,000 highly expendable “femtosatellites” to get up close and personal with the most spectacular rings in our solar system.
The galaxy is littered with rogue planets, worlds flung out of the systems that built them, drifting between the stars with no sun to call their own. But when a planet is torn away, does anything go with it? New simulations say yes, a passing star can rip a world out of its orbit and leave its moons still faithfully circling it, sailing off into the dark as a set. If our own Jupiter were evicted tomorrow, all four Galilean moons would go with it. And in that darkness, with no sunlight at all, one of those moons might still be warm enough for an ocean.
The planet Mercury is the first planet from the Sun but also one shrouded in mystery. This is primarily due to the limited number of spacecrafts that have visited it, but this limited data has provided scientists with new and exciting characteristics previously thought impossible. One fascinating aspect is its magnetic field, which was first discovered in March 1974, which both surprised and puzzled scientists due to the planet’s small size, which is measured at about half the size of the continental United States from coast to coast.
A new study presented at the Royal Astronomical Society's National Astronomy Meeting suggests that solar storms may warm the Martian lower atmosphere, but only when they strike during a major Martian dust storm. The discovery was accidental, emerging from a search for a different effect entirely, and hints that the weather system on Mars may be more tangled and interconnected than scientists previously assumed.