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Categories: Space: The Solar System
Published Satellite security lags decades behind the state of the art
(via sciencedaily.com) Original source Researchers have tested the software of three satellites. And they found many standard security mechanisms missing.
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 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 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.
Published Scientists report 'benchmarks' for extreme space weather
(via sciencedaily.com) Original source Extreme space weather threatens vital satellites orbiting the Earth, including the Global Navigation Satellite Systems (GNSS) which pass through the heart of the outer radiation belt. New research has now determined a series of benchmarks for the likely severity of extreme space weather events in GPS orbit.
Published Earth was created much faster than we thought: This makes the chance of finding other habitable planets in the Universe more likely
(via sciencedaily.com) Original source Over the past decades, researchers thought Earth was created over a period of more than 100 million years. However, a new study from suggests that the creation of Earth was much more rapid, and that water and other essential ingredients for life were delivered to Earth very early on.
Published A scorching-hot exoplanet scrutinized by astronomers
(via sciencedaily.com) Original source Through the Gemini-North Telescope in Hawai'i, the chemical composition of WASP-76 b is revealed in unprecedented detail, giving new insights also into the composition of giant planets.
Published Plate tectonics not required for the emergence of life
(via sciencedaily.com) Original source New finding contradicts previous assumptions about the role of mobile plate tectonics in the development of life on Earth. Moreover, the data suggests that 'when we're looking for exoplanets that harbor life, the planets do not necessarily need to have plate tectonics,' says the lead author of a new paper.
Published Sun's coldest region stores secret to heating million-degree corona
(via sciencedaily.com) Original source Researchers have unveiled the discovery of intense wave energy from a relatively cool, dark and strongly magnetized plasma region on the Sun, capable of traversing the solar atmosphere and maintaining temperatures of a million degrees Kelvin inside the corona. Researchers say the finding is the latest key to unraveling a host of related mysteries pertaining to Earth's nearest star.