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Abortion Bans in Arizona and Florida Will Face Voters in November
The state supreme courts in Florida and Arizona both recently ruled that strict abortion bans could go into effect. But ballot measures may give voters a chance to weigh in
Watch 'Devil Comet' approach the sun during explosive coronal mass ejection (video)
Japanese satellite will beam solar power to Earth in 2025
You Quit Ozempic or Wegovy. What Happens Next?
Many researchers think that Wegovy and Ozempic should be taken for life, but myriad factors can force people off the drugs
Anti-Trans Efforts Use Misinformation, Epistemological Violence and Gender Essentialism
Three types of misinformation are being used against transgender people: oversimplifying scientific knowledge, fabricating and misinterpreting research and promoting false equivalences
The Giant Planets Migrated Between 60-100 Million Years After the Solar System Formed
Untangling what happened in our Solar System tens or hundreds of millions of years ago is challenging. Millions of objects of wildly different masses interacted for billions of years, seeking natural stability. But its history—including the migration of the giant planets—explains what we see today in our Solar System and maybe in other, distant solar systems.
New research shows that giant planet migration began shortly after the Solar System formed.
Planetary migration is a well-established idea. The Grand-Tack Hypothesis says that Jupiter formed at 3.5 AU, migrated inward to 1.5 AU, and then back out again to 5.2 AU, where it resides today. Saturn was involved, too. Migration can also explain the Hot Jupiters we see orbiting extremely close to their stars in other solar systems. They couldn’t have formed there, so they must have migrated there. Even rocky planets can migrate early in a solar system’s history.
New research in the journal Science establishes dates for giant planet migration in our Solar System. Its title is “Dating the Solar System’s giant planet orbital instability using enstatite meteorites.” The lead author is Dr. Chrysa Avdellidou from the University of Leicester’s School of Physics and Astronomy.
“The question is, when did it happen?” Dr. Avdellidou asked. “The orbits of these planets destabilised due to some dynamical processes and then took their final positions that we see today. Each timing has a different implication, and it has been a great matter of debate in the community.”
“What we have tried to do with this work is to not only do a pure dynamical study, but combine different types of studies, linking observations, dynamical simulations, and studies of meteorites.”
The meteorites in this study are enstatites or E-type asteroids. E-type asteroids have enstatite (MgSiO3) achondrite surfaces. Achondrite means they lack chondrules, grains of rock that were once molten before being accreted to their parent body. Specifically, this group of meteorites are the low-iron chondrites called ELs.
When giant planets move, everything else responds. Tiny asteroids are insignificant compared to Jupiter’s mass. Scientists think E-type asteroids were dispersed during the gas giants’ outward migration. They may even have been the impactors in the hypothetical Late Heavy Bombardment.
Artist concept of Earth during the Late Heavy Bombardment period. Scientists have wondered if E-type asteroids disturbed during giant planet migration could’ve been responsible for the Bombardment, but the authors of this research don’t favour that explanation. Credit: NASA’s Goddard Space Flight Center Conceptual Image Lab.Enstatite achondrites that have struck Earth have similar compositions and isotope ratios as Earth. This signals that they formed in the same part of the protoplanetary disk around the young Sun. Previous research by Dr. Avdellidou and others has linked the meteorites to a population of fragments in the asteroid belt named Athor.
This work hinges on linking meteorites to parent asteroids and measuring the isotopic ratios.
“If a meteorite type can be linked to a specific parent asteroid, it provides insight into the asteroid’s composition, time of formation, temperature evolution, and original size,” the authors explain. When it comes to composition, isotopic abundances are particularly important. Different isotopes decay at different rates, so analyzing their ratio tells researchers when each meteorite closed, meaning when it became cool enough that there was no more significant diffusion of isotopes. “Therefore, thermochronometers in meteorites can constrain the epoch at which major collisional events disturbed the cooling curves of the parent asteroid,” the authors explain.
The team’s research shows that Athor is a part of a once much larger parent body that formed closer to the Sun. It also suffered from a collision that reduced its size out of the asteroid belt.
Athor found its way back when the giant planets migrated. Athor was at the mercy of all that shifting mass and underwent its own migration back into the asteroid belt. Analysis of the meteorites showed that this couldn’t have happened earlier than 60 million years ago. Other research into asteroids in Jupiter’s orbit showed it couldn’t have happened later than 100 million years ago. Since the Solar System formed about 4.56 billion years ago, the giant planet migration happened between 4.5 and 4.46 billion years ago.
This schematic from the research shows what the researchers think happened. Red circles are planetesimals (and their fragments) from the terrestrial planet region. The black solid curves roughly denote the boundary of the current asteroid inner main belt. Eccentricity increases from bottom to top.A shows the formation and cooling of the EL parent planetesimal in the terrestrial planet region before 60 Myr after Solar System formation. In this period, the terrestrial planets began scattering planetesimals to orbits with high eccentricity and semimajor axes corresponding to the asteroid main belt. B shows that between 60 and 100 Myr, the EL planetesimal was destroyed by an impact in the terrestrial planet region. At least one fragment (the Athor family progenitor) was scattered by the terrestrial planets into the scattered disk, as in (A). Then the giant planet instability implanted it into the inner main belt by decreasing its eccentricity. C shows that a few tens of millions of years after the giant planet instability occurred, a giant impact between the planetary embryo Theia and proto-Earth formed the Moon. D shows that the Athor family progenitor experienced another impact event that formed the Athor family at ~1500 Myr. Image Credit: Avdellidou et al. 2024.
Another important event happened right around the same time. About 4.5 billion years ago, a protoplanet named Theia smashed into Earth, creating the Moon. Could it all be related?
“The formation of the Moon also occurred within the range that we determined for the giant planet instability,” the authors write in their research. “This might be a coincidence, or there might be a causal relationship between the two events.”
“It’s like you have a puzzle, you understand that something should have happened, and you try to put events in the correct order to make the picture that you see today,” Dr. Avdellidou said. “The novelty with the study is that we are not only doing pure dynamical simulations, or only experiments, or only telescopic observations.”
“There were once five inner planets in our Solar System and not four, so that could have implications for other things, like how we form habitable planets. Questions like, when exactly objects came delivering volatile and organics to our planet to Earth and Mars?”
Artist’s impression of the impact that caused the formation of the Moon. Could giant planet migration have caused that impact? Credit: NASA/GSFCThe Solar System’s history is a convoluted, beautiful puzzle that somehow led to us. Everything had to work out for life to arise on Earth, sustain itself, and evolve for so long. The epic migration of the gas giants must have played a role, and this research brings its role into focus.
Never mind habitability, complex life, and civilization, the migration may have allowed Earth to form in the first place.
“The timing is very important because our Solar System at the beginning was populated by a lot of planetesimals,” said study co-author Marco Delbo, Director of Research at France’s Nice Observatory. “And the instability clears them, so if that happens 10 million years after the beginning of the Solar System, you clear the planetesimals immediately, whereas if you do it after 60 million years you have more time to bring materials to Earth and Mars.”
The post The Giant Planets Migrated Between 60-100 Million Years After the Solar System Formed appeared first on Universe Today.
Your genes may influence how much you enjoy listening to music
Your genes may influence how much you enjoy listening to music
Join NASA in Celebrating Earth Day 2024 by Sharing a #GlobalSelfie
NASA invites you — and everyone else on the planet — to take part in a worldwide celebration of Earth Day with the agency’s #GlobalSelfie event. While NASA satellites constantly look at Earth from space, on Earth Day we’re asking you to step outside and take a picture of yourself in your corner of the world. Then post it to social media using the hashtag #GlobalSelfie.
Bonus points if your #GlobalSelfie features your favorite body of water! About 71% of our Blue Marble is covered by water, and that water is one of the main reasons why Earth is like no other planet we’ve found in this solar system, or beyond.
Why #GlobalSelfie?
NASA astronauts brought home the first ever images of the whole planet from space. Now NASA satellites capture new images of Earth every second. With Earth-observing missions orbiting our home planet right now, and more set to launch this year, NASA studies Earth’s atmosphere, land and oceans in all their complexity.
For Earth Day, we want everyone to share the planet from their point of view. Need an idea of what kind of picture to take? Get outside and show us mountains, parks, the sky, rivers, lakes – and you! Wherever you are, there’s your picture.
How do I take part?
Post your photo to social media using the hashtag #GlobalSelfie. Make it public so we can see, and celebrate #EarthDay with you!
China's experimental moon satellites beam back lunar imagery (video, photo)
Could JWST Solve One of Cosmology's Greatest Mysteries?
The telescope's studies could help end a long-standing disagreement over the rate of cosmic expansion. But scientists say more measurements are needed
NASA Selects New Aircraft-Driven Studies of Earth and Climate Change
5 min read
NASA Selects New Aircraft-Driven Studies of Earth and Climate ChangeNASA has selected six new airborne missions that include domestic and international studies of fire-induced clouds, Arctic coastal change, air quality, landslide hazards, shrinking glaciers, and emissions from agricultural lands. NASA’s suite of airborne missions complement what scientists can see from orbit, measure from the ground, and simulate in computer models.
Funded through the agency’s Earth Venture program, the missions center around the use of instruments mounted on aircraft to make measurements in finer detail—both in spatial resolution and shorter time scales—than can be made by many satellites. Competitively selected, the missions provide opportunities to supplement satellite observations and make innovative measurements.
“These missions will help us interpret what our current satellites are seeing from space and test new ideas and techniques for our upcoming Earth System Observatory,” said Karen St. Germain, director of NASA’s Earth Science Division. “There is also a strong focus on actionable Earth science—gathering fundamental observations that have connections to our economy and societal decision-making and information needs.”
NASA’s newest Earth Ventures missions include studies of how climate change is altering carbon emissions and water and ice flows across Arctic coastal regions. Credit: Landsat/USGS/NASA Earth ObservatoryRoughly $120 million has been allotted for the six missions, which will deploy at various times from 2026 to 2029. Three lead investigators were chosen for each mission, with at least one required to be an early career scientist. Full staffing of the science teams and selection of complementary instruments will be competed in the coming months. These changes in the selection process were made to promote diversity, equity, and inclusion in the teams.
“We are constantly looking to foster the growth of the next generation of scientists,” said Barry Lefer, the program manager who led the Earth Venture selection panels at NASA Headquarters in Washington. “This round of missions will put an extra emphasis on bringing new people into mission planning and leadership.”
The six missions include:
Arctic coastal changeMaria Tzortziou of the City College of New York will lead a project to observe changes in river systems on the North Slope of Alaska. Known as FORTE (short for Arctic Coastlines–The Frontlines of Rapidly Transforming Ecosystems), the project will combine optical and radar measurements from planes, helicopters, boats, and drones to measure water flows and chemistry and observe how ecosystems respond to changing climate. The team will collaborate with indigenous communities to sustain observations over time.
Clouds created by fire In one of NASA’s newest Earth Ventures missions, researchers will investigate the conditions that lead to the formation of pyrocumulonimbus “fire clouds.” Extreme wildland fires can create their own weather and inject smoke into the stratosphere. Courtesy of David Peterson, U.S. Naval Research LaboratoryIn PYREX—the Pyrocumulonimbus Experiment—David Peterson of the Naval Research Laboratory in Washington will lead a study of pyrocumulonimbus clouds, which form when wildfires burn hot enough to make their own weather. Flying over the western U.S. and Canada, researchers will examine the fire characteristics that produce pyrocumulonimbus, while exploring the mechanisms that lead these clouds to inject smoke into the stratosphere, where it can have climate effects.
Urban air pollutionJames Crawford of NASA’s Langley Research Center in Hampton, Virginia, will lead HAMAQ (Hemispheric Airborne Measurements of Air Quality), a project that capitalizes on the recent launches of NASA’s TEMPO pollution-monitoring satellite instrument and comparable measurements made by Korean and European satellites. Over Mexico City and a U.S. city to be determined, scientists will investigate areas of poor air quality and test how satellite information can help improve ground-based forecasting and mitigation strategies.
Shifting weather, shifting landsClimate change is leading to more extreme droughts and rainfall events that affect the stability of hillslopes and the soil and rock on them. Led by Alexander Handwerger of NASA’s Jet Propulsion Laboratory in Pasadena, California, LACCE (Landslide Climate Change Experiment) will combine airborne measurements with land-based sensors to track the way slopes and landslides are changing as water moves differently across the landscape.
Glacier retreatJohn Holt of the University of Arizona will lead Snow4Flow, a project to quantify the retreat of glaciers and ice sheets in ways that can lead to better projections of land-ice change. In Alaska, southeastern Greenland, the Canadian Arctic, and Svalbard, the team will use microwave and high-frequency radar sounders to measure snow accumulation, ice melting, and changes in ice thickness and motion.
Agricultural emissionsWhile the burning of fossil fuels remains the leading source of carbon in our atmosphere, farmlands and ranchlands are also substantial sources of gas and particle emissions. In the NTERFAACE (Nitrogen and Carbon Terrestrial Fluxes: Agriculture, Atmospheric Composition, and Ecosystems) mission, led by Glenn Wolfe of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, researchers will measure the amount of greenhouse gases, nitrogen, and other pollutants that are emitted from agricultural lands across the United States.
The PYREX and Snow4Flow missions are funded at $30 million each, while the other four projects will each receive $15 million. These six investigations were selected from 42 proposals. The 2024 selections represent the fourth series of NASA Earth Venture investigations, which were first recommended by the National Research Council in 2007.
For more on NASA Earth Science, visit: science.nasa.gov/earth
Share Details Last Updated Apr 19, 2024 Contact Michael Carlowicz michael.j.carlowicz@nasa.gov Location Goddard Space Flight Center Related Terms Explore More 4 min read AI for Earth: How NASA’s Artificial Intelligence and Open Science Efforts Combat Climate ChangeArticle
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Hubble Captures a Bright Galactic and Stellar Duo
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Hubble Captures a Bright Galactic and Stellar Duo This image from the NASA/ESA Hubble Space Telescope features the barred spiral galaxy NGC 3783. ESA/Hubble & NASA, M. C. Bentz, D. J. V. RosarioThis image from the NASA/ESA Hubble Space Telescope features NGC 3783, a bright barred spiral galaxy about 130 million light-years from Earth that also lends its name to the eponymous NGC 3783 galaxy group. Like galaxy clusters, galaxy groups are aggregates of gravitationally bound galaxies. Galaxy groups, however, are less massive and contain fewer members than galaxy clusters do: whereas galaxy clusters can contain hundreds or even thousands of constituent galaxies, galaxy groups do not typically include more than 50. The Milky Way is actually part of a galaxy group, known as the Local Group, which also holds two other large galaxies (Andromeda and the Triangulum galaxy), as well as several dozen satellite and dwarf galaxies. The NGC 3783 galaxy group contains 47 galaxies. It also seems to be at a fairly early stage of its evolution, making it an interesting object to study.
While the focus of this image is the spiral galaxy NGC 3783, the eye is equally drawn to the very bright object in the lower right part of this image. This is the star HD 101274. The perspective in this image makes the star and the galaxy look like close companions, but this is an illusion. HD 101274 lies only about 1,530 light-years from Earth, it is about 85,000 times closer than NGC 3783. This explains how a single star can appear to outshine an entire galaxy!
NGC 3783 is a type-1 Seyfert galaxy, which is a galaxy with a bright central region. Hubble captures it in incredible detail, from its glowing central bar to its narrow, winding arms and the dust threaded through them, thanks to five separate images taken in different wavelengths of light. In fact, the galactic center is so bright that it exhibits diffraction spikes, normally only seen on stars such as HD 101274.
Text credit: European Space Agency (ESA)
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Students Celebrate Rockets, Environment at NASA’s Kennedy Space Center
At NASA’s Kennedy Space Center, sustainability and preservation efforts here on Earth are as much of a priority as rocket launches, spacecraft, and the exploration of worlds beyond our own.
In celebration of Earth Day 2024, nearly 100 students from Andrew Jackson Middle School in Titusville, Florida, and a virtual audience of students across the country, attended NASA’s Next Gen STEM Earth Day panel at the NASA News Center’s John Holliman Auditorium and press site “bullpen.”
On hand were NASA environmental and educational experts who discussed Kennedy’s unique role balancing space launch technology and protected habitat, the center’s new electric vehicle charging stations, and NASA’s Earthrise educational initiative that aims to increase science, technology, engineering, and mathematics literacy.
Bob Kline, acting chief of Kennedy’s Environmental Assurance Branch, helped students learn about the importance of protecting the habitat that is refuge to more than 1,500 species of plants and animals. NASA Kennedy shares a boundary with the Merritt Island National Wildlife Refuge and the Canaveral National Seashore, which encompass over 140,000 acres of land, waters, and protected habitats.
“Because we’re a wildlife refuge, it’s easy to think the launches would impact the wildlife, but it’s mostly the buildings that might get impacted by wildlife trying to live on them,” said Kline. “During renovations we’ve had to do special things to protect bats and other birds who live in roofs or under bridges. Everything we do, we’re very mindful of the animals, whether they’re endangered or not. We care about them deeply.”
Panelist Kim King-Wrenn, a park ranger from Merritt Island National Wildlife Refuge, echoed Kline’s message. She told students that the spaceport is one of the most biologically diverse places in the world.
Home to everything from the Florida scrub jay to endangered green sea turtles, King-Wrenn classifies Kennedy as the goldilocks of climate zones.
“Right here is where the northern temperate zone and the southern, subtropical zones come together,” King-Wrenn said. “The more habitat diversity there is, the more diverse homes there are for more kinds of animals.”
Students like 7th grader Zoe Oderman were fascinated by the coexistence of nature and technology across the spaceport. “The Vehicle Assembly Building was awesome, but I love that the beaches at Kennedy Space Center give turtles a place to lay their eggs, because other places in the area don’t,” Oderman said.
Kennedy employee Spencer Davis discussed the installation of 56 electric vehicle charging stations during his time at the NASA Transportation Office on center. The new infrastructure helps support a fleet of electric government vehicles including the all-electric crew transport vehicles that will take Artemis astronauts from their crew quarters to the launch pad.
Students from Andrew Jackson Middle School in Titusville, Florida, pose for a photo with one of the Artemis crew transportation vehicles in front of the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on Tuesday, April 2, 2024. As part of NASA’s NextGen STEM project, the students joined others from across the country who participated virtually for an environmentally focused Earth Day briefing held inside Kennedy’s news auditorium to discuss how technology and science coexist with nature at the spaceport. NASA/Kim ShiflettLater this summer, Davis and his team will be honored at the White House for these efforts to facilitate a future of zero carbon emission government vehicles and help save taxpayer money.
“The big takeaway here is in order to charge up and drive one of Kennedy’s Chevrolet Bolts 100 miles, it only costs $2.80,” Davis said. “That’s basically the price of a soft drink.”
The students also learned about Earthrise from panelist Kelly McCarthy, program specialist with NASA’s Office of STEM Engagement at the agency’s Stennis Space Center in Mississippi.
The NASA education initiative provides educators with access to monthly collections of resources aimed at increasing STEM literacy and understanding the importance of protecting our home planet.
“Earthrise is a really good way to find out the most relevant and useful solutions-based resources that exist right now,” McCarthy said.
Besides offering their expertise on sustainable practices as well as words of encouragement to the future stewards of our planet, the panelists inspired students to pursue STEM careers, including at Kennedy.
“You can do anything you want to do out here, and if you really apply yourself you can get into any field,” Davis told the students. “Don’t be afraid to step outside the box. Don’t be afraid to do something completely different, even if it’s scary. Take every opportunity and seize the moment.”
The event was coordinated through the Next Gen STEM project in NASA’s Office of STEM Engagement, which reaches students in schools and informal classrooms across the county.
View NASA’s Next Gen STEM Earth Day Student Briefing here:
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Week in images: 15-19 April 2024
Week in images: 15-19 April 2024
Discover our week through the lens