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Categories: Physics: General, Space: The Solar System
Published Gauging the strength of ancient and active rivers beyond Earth
(via sciencedaily.com) Original source A new technique allows scientists to see how intensely rivers used to flow on Mars, and how they currently flow on Titan. The method uses satellite observations to estimate the rate at which rivers move fluid and sediment downstream.
Published Why the day is 24 hours long: Astrophysicists reveal why Earth's day was a constant 19.5 hours for over a billion years
(via sciencedaily.com) Original source Astrophysicists have revealed how the slow and steady lengthening of Earth's day caused by the tidal pull of the moon was halted for over a billion years. They show that from approximately two billion years ago until 600 million years ago, an atmospheric tide driven by the sun countered the effect of the moon, keeping Earth's rotational rate steady and the length of day at a constant 19.5 hours. Without this billion-year pause in the slowing of our planet's rotation, our current 24-hour day would stretch to over 60 hours. The paper offers a new perspective on how global warming will affect the length of our day and validates global circulation models as a climate modelling tool.
Published Earth formed from dry, rocky building blocks
(via sciencedaily.com) Original source A new study shows that the so-called planetesimals that accreted together to form Earth must have been composed of dry, rocky materials.
Published Large sub-surface granite formation signals ancient volcanic activity on Moon's dark side
(via sciencedaily.com) Original source A large formation of granite discovered below the lunar surface likely was formed from the cooling of molten lava that fed a volcano or volcanoes that erupted early in the Moon's history -- as long as 3.5 billion years ago.
Published New image from James Webb Space Telescope reveals astonishing Saturn and its rings
(via sciencedaily.com) Original source Saturn's iconic rings seem to glow eerily in this incredible infrared picture, which also unveils unexpected features in Saturn's atmosphere. This image serves as context for an observing program that will test the telescope's capacity to detect faint moons around the planet and its bright rings. Any newly discovered moons could help scientists put together a more complete picture of the current system of Saturn, as well as its past.
Published Astrophysicists propose a new way of measuring cosmic expansion: Lensed gravitational waves
(via sciencedaily.com) Original source The universe is expanding; we've had evidence of that for about a century. But just how quickly celestial objects are receding from each other is still up for debate.
Published Gullies on Mars could have been formed by recent periods of liquid meltwater, study suggests
(via sciencedaily.com) Original source A study offers new insights into how water from melting ice could have played a recent role in the formation of ravine-like channels that cut down the sides of impact craters on Mars.
Published Life after death: Astronomers find a planet that shouldn't exist
(via sciencedaily.com) Original source The star would have inflated up to 1.5 times the planet's orbital distance -- engulfing the planet in the process -- before shrinking to its current size at only one-tenth of that distance.
Published Magnetic bacteria point the way
(via sciencedaily.com) Original source Magnetotactic bacteria, which can align with the Earth's magnetic field, have been discovered in a new location. Previously observed on land and in shallow water, analysis of a hydrothermal vent has proven that they can also survive deep under the ocean. The bacteria were able to exist in an environment that was not ideal for their typical needs. Magnetotactic bacteria are of interest not only for the role they play in Earth's ecosystem, but also in the search for extraterrestrial life. Evidence of their existence can remain in rocks for billions of years. Their magnetic inclinations can also provide a record of how magnetic poles have shifted over time. This new discovery brings hope to researchers that the magnetic bacteria might be found in yet more unexpected locations, on Earth and perhaps even on Mars or beyond.
Published Don't wait, desalinate: A new approach to water purification
(via sciencedaily.com) Original source A water purification system separates out salt and other unnecessary particles with an electrified version of dialysis. Successfully applied to wastewater with planned expansion into rivers and seas, the method saves money and saps 90% less energy than its counterparts.
Published 'Toggle switch' can help quantum computers cut through the noise
(via sciencedaily.com) Original source What good is a powerful computer if you can't read its output? Or readily reprogram it to do different jobs? People who design quantum computers face these challenges, and a new device may make them easier to solve.
Published Nanophotonics: Coupling light and matter
(via sciencedaily.com) Original source Researchers have developed a metasurface that enables strong coupling effects between light and transition metal dichalcogenides (TMDCs).
Published Einstein and Euler put to the test at the edge of the Universe
(via sciencedaily.com) Original source The cosmos is a unique laboratory for testing the laws of physics, in particular those of Euler and Einstein. Euler described the movements of celestial objects, while Einstein described the way in which celestial objects distort the Universe. Since the discovery of dark matter and the acceleration of the Universe's expansion, the validity of their equations has been put to the test: are they capable of explaining these mysterious phenomena? A team has developed the first method to find out. It considers a never-before-used measure: time distortion.
Published Molecular filament shielded young solar system from supernova
(via sciencedaily.com) Original source Isotope ratios found in meteorites suggest that a supernova exploded nearby while the Sun and Solar System were still forming. But the blast wave from a supernova that close could have potentially destroyed the nascent Solar System. New calculations shows that a filament of molecular gas, which is the birth cocoon of the Solar System, aided the capture of the isotopes found in the meteorites, while acting as a buffer protecting the young Solar System from the nearby supernova blast.
Published Combining twistronics with spintronics could be the next giant leap in quantum electronics
(via sciencedaily.com) Original source Quantum researchers twist double bilayers of an antiferromagnet to demonstrate tunable moiré magnetism.
Published Groundwork for future ultra-precise timing links to geosynchronous satellites
(via sciencedaily.com) Original source Scientists have demonstrated a capability long sought by physicists: transmitting extremely precise time signals through the air between far-flung locations at powers that are compatible with future space-based missions. The results could enable time transfer from the ground to satellites in geosynchronous orbit with femtosecond precision -- 10,000 times better than the existing state-of-the-art satellite approaches. It also would allow for successful synchronization using the bare minimum timing signal strength, which would make the system highly robust in the face of atmospheric disturbances.
Published Detection of an echo emitted by our Galaxy's black hole 200 years ago
(via sciencedaily.com) Original source An international team of scientists has discovered that Sagittarius A* (Sgr A*), the supermassive black hole at the centre of the Milky Way, emerged from a long period of dormancy some 200 years ago. The team, led by Frédéric Marin, a CNRS researcher at the Astronomical Strasbourg Observatory (CNRS/University of Strasbourg), has revealed the past awakening of this gigantic object, which is four million times more massive than the Sun. Their work is published in Nature on 21 June.
Published Exoplanet may reveal secrets about the edge of habitability
(via sciencedaily.com) Original source How close can a rocky planet be to a star, and still sustain water and life? A recently discovered exoplanet may be key to solving that mystery.
Published Jupiter's moon Europa may have had a slow evolution
(via sciencedaily.com) Original source Europa may have a metamorphic origin for the ocean. While some scientists speculated this, a research team shows that if Europa indeed formed from hydrated rocks (i.e., rocks have hydrogen and oxygen), then enough of Europa's interior should get hot enough to release water directly from the hydrated rocks to form the ocean and ice shell.
Published Researchers demystify the unusual origin of the Geminids meteor shower
(via sciencedaily.com) Original source Princeton researchers used observations from NASA's Parker Solar Probe mission to deduce that it was likely a violent, catastrophic event -- such as a high-speed collision with another body or a gaseous explosion -- that created the Geminids meteoroid stream. Mysteries surrounding the origin of the Geminids have long fascinated scientists because, while most meteor showers are created when a comet emits a tail of ice and dust, the Geminids stem from an asteroid -- a chunk of rock that normally does not produce a tail. Until now, this unusual meteoroid stream had only been studied from Earth.