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Categories: Space: Structures and Features, 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 Webb Telescope detects most distant active supermassive black hole
(via sciencedaily.com) Original source Researchers have discovered the most distant active supermassive black hole to date with the James Webb Space Telescope (JWST). The galaxy, CEERS 1019, existed about 570 million years after the big bang, and its black hole is less massive than any other yet identified in the early universe.
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 Webb locates dust reservoirs in two supernovae
(via sciencedaily.com) Original source Researchers have made major strides in confirming the source of dust in early galaxies. Observations of two Type II supernovae, Supernova 2004et (SN 2004et) and Supernova 2017eaw (SN 2017eaw), have revealed large amounts of dust within the ejecta of each of these objects. The mass found by researchers supports the theory that supernovae played a key role in supplying dust to the early universe.
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 First 'ghost particle' image of Milky Way
(via sciencedaily.com) Original source Scientists have revealed a uniquely different image of our galaxy by determining the galactic origin of thousands of neutrinos -- invisible 'ghost particles' which exist in great quantities but normally pass straight through Earth undetected. The neutrino-based image of the Milky Way is the first of its kind: a galactic portrait made with particles of matter rather than electromagnetic energy.
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 Earliest strands of the cosmic web
(via sciencedaily.com) Original source Galaxies are not scattered randomly across the universe. They gather together not only into clusters, but into vast interconnected filamentary structures with gigantic barren voids in between. This 'cosmic web' started out tenuous and became more distinct over time as gravity drew matter together.
Published Unveiling the origins of merging black holes in galaxies like our own
(via sciencedaily.com) Original source Black holes, some of the most captivating entities in the cosmos, possess an immense gravitational pull so strong that not even light can escape. The groundbreaking detection of gravitational waves in 2015, caused by the coalescence of two black holes, opened a new window into the universe. Since then, dozens of such observations have sparked the quest among astrophysicists to understand their astrophysical origins. Thanks to the POSYDON code's recent major advancements in simulating binary-star populations, a team of scientists predicted the existence of merging massive, 30 solar mass black hole binaries in Milky Way-like galaxies, challenging previous theories.
Published Gravitational waves from colossal black holes found using 'cosmic clocks'
(via sciencedaily.com) Original source You can't see or feel it, but everything around you -- including your own body -- is slowly shrinking and expanding. It's the weird, spacetime-warping effect of gravitational waves passing through our galaxy. New results are the first evidence of the gravitational wave background -- a sort of soup of spacetime distortions pervading the entire universe and long predicted to exist by scientists.
Published ALMA digs deeper into the mystery of planet formation
(via sciencedaily.com) Original source An international research team has observed disks around 19 protostars with a very high resolution to search for the earliest signs of planet formation. This survey was motivated by the recent findings that planet formation may be well-underway in the more-evolved proto-planetary disks, but until now there had been no systematic study to search for signs of planet formation in younger protostellar systems.
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 Starlight and the first black holes: researchers detect the host galaxies of quasars in the early universe
(via sciencedaily.com) Original source For the first time, the James Webb Space Telescope has revealed starlight from two massive galaxies hosting actively growing black holes -- quasars -- seen less than a billion years after the Big Bang.
Published A surprise chemical find by ALMA may help detect and confirm protoplanets
(via sciencedaily.com) Original source Scientists studying the protoplanetary disk around a young star have discovered the most compelling chemical evidence to date of the formation of protoplanets. The discovery will provide astronomers with an alternate method for detecting and characterizing protoplanets when direct observations or imaging are not possible.
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 First detection of crucial carbon molecule
(via sciencedaily.com) Original source Scientists detect a new carbon compound in space for the first time. Known as methyl cation (pronounced cat-eye-on) (CH3+), the molecule is important because it aids the formation of more complex carbon-based molecules. Methyl cation was detected in a young star system, with a protoplanetary disk, known as d203-506, which is located about 1,350 light-years away in the Orion Nebula.
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.