When the James Webb Space Telescope launched on 25 December 2021, it carried a list of 344 single points of failure. Each one was a step or a part where a single fault would have crippled the mission, with no second chance and no way to send anyone to fix it. The telescope cleared all of them. It now sits about a million miles from Earth, doing the most sensitive infrared astronomy ever attempted, on roughly the power of a household kettle.

Both halves of that are true, and both are worth taking apart, because the figures are precise and the precision is the point.

344 ways to fail

The number comes from Mike Menzel, Webb’s lead mission systems engineer at NASA, who has said the observatory launched with 344 single-point failures on its books. A single point of failure, in engineering terms, is a place where one thing going wrong takes everything with it. Most spacecraft have a handful. Webb had hundreds.

About 80 per cent of them were tied to the deployment, the slow unfolding of a telescope that had been folded up to fit inside its rocket. That sequence relied on roughly 140 release mechanisms, 70 hinge assemblies, eight motors, some 400 pulleys, and around a quarter of a mile of cable, each of which had to work on command, in order, the first time.

What made the list so unforgiving was the destination. Webb was not going to low orbit, where Hubble could be visited and repaired by astronauts five times. It was going somewhere no crew can reach, which meant the usual safety net, send someone up to fix it, did not exist. Every one of the 344 had to hold on its own.

The fortnight that decided it

The riskiest part was the sunshield, a five-layer screen the size of a tennis court that has to separate and tension without tearing or snagging. It is the single most complex deployment ever flown, and it is the reason so much of the risk was packed into the first two weeks.

The sunshield reached its final, tensioned shape on 4 January 2022, ten days after launch. The project manager at the time, Bill Ochs, told reporters that finishing it retired somewhere between 70 and 75 per cent of the single-point failures on the original list. The rest fell away as the mirror segments locked into place over the following days. By the end of the fortnight, the most dangerous machine NASA had ever unfolded had unfolded.

Less power than a kettle

Here the popular line is right, with one number worth pinning down. The spacecraft and its four instruments run on about one kilowatt. The solar array is built to deliver closer to two kilowatts, but that extra capacity is margin, sized so the telescope still has enough as the panels degrade over its mission.

So the working figure is about a kilowatt, and a lot of household kettles draw more than that, particularly the three-kilowatt kind common outside North America. A telescope unpacking the early universe really does run on less electricity than the appliance that makes your tea.

The reason it can is the sunshield again. Webb has to keep its detectors extraordinarily cold, down to around 7 kelvin on one instrument, and cooling is usually the most power-hungry thing a cold spacecraft does. By parking the sunshield between the telescope and the Sun, Webb does most of that cooling passively, simply by sitting in deep shade, rather than by running power-hungry refrigeration. The shade that protects it also keeps its electricity bill tiny.

A million miles out

That deep shade only works at the right address. Webb orbits the Sun-Earth point known as L2, about 1.5 million kilometres away, near enough a million miles, where it can keep the Sun, Earth, and Moon all behind a single shield.

It also means the telescope is on its own. The same distance that makes the observatory work is the distance that made the 344 single points of failure so tense, because none of them could be reached if they jammed. The achievement was not just building something this delicate. It was building something this delicate that had to survive its own unpacking, unattended, a million miles from the nearest spanner.

It has been returning science since July 2022.

The list of 344 is now history, which is the only acceptable place for a list like that to end up.

The post 344 steps stood between the James Webb Space Telescope and total failure — any one could have ended it — and the telescope that survived them all now runs on less power than a household kettle, a million miles from Earth appeared first on Space Daily.

Even small asteroids lead complex lives. During its flyby of the asteroid Donaldjohanson last year, NASA’s Lucy spacecraft revealed the asteroid to be a wobbly, peanut-shaped body that has undergone a lot of activity in its relatively short history. Formed as fragments coalesced after a violent collision 155 million years ago, the asteroid was transformed by the small but inexorable force of the Sun’s radiation, all while retaining signs of the brief presence of liquid water in its distant past.

Zooming through the main asteroid belt toward one of the Jupiter Trojan asteroid groups, the Lucy spacecraft collected the first close-up images and other data at Donaldjohanson on April 20, 2025, as it passed 650 miles away from the asteroid. The data revealed that, instead of spinning simply around one axis like most other asteroids and planets, Donaldjohanson has a more complicated two-axis rotation. Scientists also saw Donaldjohanson’s peanut shape and the craters and ridges on its surface.

Lucy’s encounter with the asteroid was planned as a dress rehearsal for the spacecraft and mission team before its primary asteroid encounters, which begin with Lucy’s flyby of the Trojan asteroid Eurybates on Aug. 12, 2027. The instruments performed as expected, and, as a bonus, scientists got a rare opportunity to study a previously unexplored asteroid up close and to compare it to two asteroids with similar compositions but different histories: Bennu, the target of NASA’s OSIRIS-REx sample-return mission, and Ryugu, the site of JAXA’s (Japan Aerospace Exploration Agency) Hayabusa2 sample-return mission.

Here’s what Lucy’s science team has learned so far from Lucy’s encounter with Donaldjohanson, as reported on June 18 in the journal Science.

Wobbling rotation

With Earth-based telescopes, observers saw fluctuations in the light Donaldjohanson reflects, regular patterns of peaks and valleys, typical of an elongated object rotating once every 10.5 Earth days. But Lucy’s data revealed another pattern: Donaldjohanson appears to be rotating like a wobbly top. Paper authors reported that the asteroid rotates end-over-end once every 10.5 Earth days, and wobbles back and forth around its long axis once every 26.5 days.

Peanut shape

While the Earth-based observations hinted at Donaldjohanson’s elongated shape, the Lucy flyby revealed a “bilobate” structure: two lobes connected by a neck, like a peanut. These lobes are likely two fragments from an asteroid collision that gently came together afterward by their mutual gravity.

Donaldjohanson likely rotated at least 10 times faster when it formed, having slowed to its current rate in the last 20 to 60 million years, the team estimates. As it slowed, the balance between the centrifugal force pushing things apart and gravity pulling things together changed and loose rocky material slid down slopes creating the worn-down appearance of many craters, as the flyby images showed.

The paper’s authors say that the asteroid’s slowing rotation is likely caused by a subtle consequence of solar heating known as the YORP effect. Each part of the asteroid’s Sun-warmed surface radiates heat away as infrared light, and that radiation imparts a tiny recoil force to the surface. Because the asteroid’s shape isn’t symmetric, this results in a net torque, or twist, that can change the asteroid’s rotation. Thus, YORP can slow asteroid spins down or speed them up, as in the case of Bennu (once every four hours) and Ryugu (once about every seven hours), which both likely used to rotate much slower than they do today.

Fleeting water

As it passed by Donaldjohanson at 30,000 mph, Lucy recorded the signatures of iron-rich clay minerals on the surface. These clays must have formed in the distant past with the help of liquid water. However, the exposure must have been brief, Lucy scientists concluded, because iron in clays tends to be replaced with other elements, such as magnesium, as water lingers.

Indeed, scientists saw magnesium-rich clays at Bennu and Ryugu, which suggested prolonged water exposure, perhaps lasting millions of years, when they were still part of larger asteroids.

This difference in water exposure history, and other characteristics, may mean that the parent bodies of these asteroids formed at different times or in different regions of the solar system before relocating to the main belt.

Compare, contrast

Donaldjohanson is thought to be made from rocky remnants of a larger, carbon- and water-rich asteroid that collided with another object in the main asteroid belt. Bennu and Ryugu are thought to have formed in the same way and in the same region.

But Donaldjohanson is different. At 155 million years old, it is much younger than Bennu and Ryugu, which formed 1 to 2 billion years ago. Donaldjohanson also has remained in the asteroid belt since birth, while its wandering cousins migrated into orbits around the Sun that bring them close to Earth’s orbit about once a year (which made them perfect close targets for sample return missions).

“It’s helpful for scientists to compare Donaldjohanson with asteroids like Bennu and Ryugu, which are seemingly similar asteroids, because every subtle difference is another clue to our origin story,” said Simone Marchi, Lucy deputy principal investigator and lead author of the study at the Boulder, Colorado, office of the Southwest Research Institute.

“Once we start learning more about the Trojans, a completely different population of space rocks with very different histories, our understanding of solar system formation is destined to be challenged,” said Marchi.

Named after a fossilized skeleton of a human ancestor discovered in Ethiopia in 1974, NASA’s Lucy will be the first mission to explore Jupiter’s Trojan asteroids, a population of well-preserved space rocks that formed early in our solar system’s history and could help scientists understand how the planets formed and moved around before settling in their current configuration.

Download story graphics from NASA’s Scientific Visualization Studio.

About Lucy:

Lucy’s principal investigator is based out of the Boulder, Colorado, branch of Southwest Research Institute, headquartered in San Antonio. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, provides overall mission management, systems engineering, and safety and mission assurance. Lockheed Martin Space in Littleton, Colorado, built the spacecraft. Lucy is the 13th mission in NASA’s Discovery Program. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Discovery Program for the agency’s Science Mission Directorate in Washington.

For more information on NASA’s Lucy mission, visit:

By Lonnie Shekhtman

NASA’s Goddard Space Flight Center, Greenbelt, Md.

and

Katherine Kretke

Southwest Research Institute, Boulder, Colo.

Media Contacts:

Karen Fox / Molly Wasser

Headquarters, Washington
240-285-5155 / 240-419-1732
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

Sarah Frazier

NASA’s Goddard Space Flight Center, Greenbelt, Md.
202-853-7191
sarah.frazier@nasa.gov

The post NASA’s Lucy Reveals Wobbling, Peanut-Shaped Asteroid appeared first on NASA Science.

Even small asteroids lead complex lives. During its flyby of the asteroid Donaldjohanson last year, NASA’s Lucy spacecraft revealed the asteroid to be a wobbly, peanut-shaped body that has undergone a lot of activity in its relatively short history. Formed as fragments coalesced after a violent collision 155 million years ago, the asteroid was transformed by the small but inexorable force of the Sun’s radiation, all while retaining signs of the brief presence of liquid water in its distant past.

Zooming through the main asteroid belt toward one of the Jupiter Trojan asteroid groups, the Lucy spacecraft collected the first close-up images and other data at Donaldjohanson on April 20, 2025, as it passed 650 miles away from the asteroid. The data revealed that, instead of spinning simply around one axis like most other asteroids and planets, Donaldjohanson has a more complicated two-axis rotation. Scientists also saw Donaldjohanson’s peanut shape and the craters and ridges on its surface.

Lucy’s encounter with the asteroid was planned as a dress rehearsal for the spacecraft and mission team before its primary asteroid encounters, which begin with Lucy’s flyby of the Trojan asteroid Eurybates on Aug. 12, 2027. The instruments performed as expected, and, as a bonus, scientists got a rare opportunity to study a previously unexplored asteroid up close and to compare it to two asteroids with similar compositions but different histories: Bennu, the target of NASA’s OSIRIS-REx sample-return mission, and Ryugu, the site of JAXA’s (Japan Aerospace Exploration Agency) Hayabusa2 sample-return mission.

Here’s what Lucy’s science team has learned so far from Lucy’s encounter with Donaldjohanson, as reported on June 18 in the journal Science.

Wobbling rotation

With Earth-based telescopes, observers saw fluctuations in the light Donaldjohanson reflects, regular patterns of peaks and valleys, typical of an elongated object rotating once every 10.5 Earth days. But Lucy’s data revealed another pattern: Donaldjohanson appears to be rotating like a wobbly top. Paper authors reported that the asteroid rotates end-over-end once every 10.5 Earth days, and wobbles back and forth around its long axis once every 26.5 days.

Peanut shape

While the Earth-based observations hinted at Donaldjohanson’s elongated shape, the Lucy flyby revealed a “bilobate” structure: two lobes connected by a neck, like a peanut. These lobes are likely two fragments from an asteroid collision that gently came together afterward by their mutual gravity.

Donaldjohanson likely rotated at least 10 times faster when it formed, having slowed to its current rate in the last 20 to 60 million years, the team estimates. As it slowed, the balance between the centrifugal force pushing things apart and gravity pulling things together changed and loose rocky material slid down slopes creating the worn-down appearance of many craters, as the flyby images showed.

The paper’s authors say that the asteroid’s slowing rotation is likely caused by a subtle consequence of solar heating known as the YORP effect. Each part of the asteroid’s Sun-warmed surface radiates heat away as infrared light, and that radiation imparts a tiny recoil force to the surface. Because the asteroid’s shape isn’t symmetric, this results in a net torque, or twist, that can change the asteroid’s rotation. Thus, YORP can slow asteroid spins down or speed them up, as in the case of Bennu (once every four hours) and Ryugu (once about every seven hours), which both likely used to rotate much slower than they do today.

Fleeting water

As it passed by Donaldjohanson at 30,000 mph, Lucy recorded the signatures of iron-rich clay minerals on the surface. These clays must have formed in the distant past with the help of liquid water. However, the exposure must have been brief, Lucy scientists concluded, because iron in clays tends to be replaced with other elements, such as magnesium, as water lingers.

Indeed, scientists saw magnesium-rich clays at Bennu and Ryugu, which suggested prolonged water exposure, perhaps lasting millions of years, when they were still part of larger asteroids.

This difference in water exposure history, and other characteristics, may mean that the parent bodies of these asteroids formed at different times or in different regions of the solar system before relocating to the main belt.

Compare, contrast

Donaldjohanson is thought to be made from rocky remnants of a larger, carbon- and water-rich asteroid that collided with another object in the main asteroid belt. Bennu and Ryugu are thought to have formed in the same way and in the same region.

But Donaldjohanson is different. At 155 million years old, it is much younger than Bennu and Ryugu, which formed 1 to 2 billion years ago. Donaldjohanson also has remained in the asteroid belt since birth, while its wandering cousins migrated into orbits around the Sun that bring them close to Earth’s orbit about once a year (which made them perfect close targets for sample return missions).

“It’s helpful for scientists to compare Donaldjohanson with asteroids like Bennu and Ryugu, which are seemingly similar asteroids, because every subtle difference is another clue to our origin story,” said Simone Marchi, Lucy deputy principal investigator and lead author of the study at the Boulder, Colorado, office of the Southwest Research Institute.

“Once we start learning more about the Trojans, a completely different population of space rocks with very different histories, our understanding of solar system formation is destined to be challenged,” said Marchi.

Named after a fossilized skeleton of a human ancestor discovered in Ethiopia in 1974, NASA’s Lucy will be the first mission to explore Jupiter’s Trojan asteroids, a population of well-preserved space rocks that formed early in our solar system’s history and could help scientists understand how the planets formed and moved around before settling in their current configuration.

Download story graphics from NASA’s Scientific Visualization Studio.

About Lucy:

Lucy’s principal investigator is based out of the Boulder, Colorado, branch of Southwest Research Institute, headquartered in San Antonio. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, provides overall mission management, systems engineering, and safety and mission assurance. Lockheed Martin Space in Littleton, Colorado, built the spacecraft. Lucy is the 13th mission in NASA’s Discovery Program. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Discovery Program for the agency’s Science Mission Directorate in Washington.

For more information on NASA’s Lucy mission, visit:

By Lonnie Shekhtman

NASA’s Goddard Space Flight Center, Greenbelt, Md.

and

Katherine Kretke

Southwest Research Institute, Boulder, Colo.

Media Contacts:

Karen Fox / Molly Wasser

Headquarters, Washington
240-285-5155 / 240-419-1732
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

Sarah Frazier

NASA’s Goddard Space Flight Center, Greenbelt, Md.
202-853-7191
sarah.frazier@nasa.gov

Wealth tax criticized by billionaires and Gavin Newsom would levy a one-time 5% tax on residents worth over $1bn

A popular proposal in California to impose a wealth tax on billionaires has gained enough signatures to qualify for the ballot in November, state officials announced on Wednesday.

The news is set to intensify an already heated debate around the tax, which has pitted tech moguls and the state’s governor, Gavin Newsom, against the labor union backing the measure.

Top 10% generate climate and biodiversity damage bill that exceeds economies of most countries, say researchers

The environmental damage bill racked up by the highest-consuming 10% of the world’s population has reached up to $5.7tn a year – larger than the economy of every country except the US and China, a study has found.

Mega-consumers in this group are concentrated in the global north, accounting for more than half the population of the US and 40-45% of people in the EU.

One messy database is threatening to disenfranchise thousands or even millions of registered voters, while leaving even more at risk of intimidation or data breaches, in the name of solving a problem that barely exists.

As the 2026 midterm elections approach, election and privacy experts are sounding alarms about the Department of Homeland Security's Systematic Alien Verification for Entitlements (SAVE) Program, which President Donald Trump's administration has expanded to ostensibly catch noncitizens voting. Experts say that amounts to a dangerous, error-prone effort to centralize voter data. "The federal government doesn't have the author …

Read the full story at The Verge.

Relativity Space has reached orbit exactly zero times. Its only rocket flew once, in March 2023, climbed cleanly through the hardest part of the atmosphere, and then a second-stage engine quit and the vehicle fell into the Atlantic a few minutes after liftoff. On June 17, 2026, that same company announced it would build and fly a science orbiter to Mars in 2028 anyway.

The mission is the first under a newly created Interplanetary Sciences Program, run under CEO Eric Schmidt. It would carry a NASA instrument suite, double as a communications relay for whatever is operating on the Martian surface, and be paid for not by the agency but by a philanthropic backer Relativity has declined to name.

The rocket that flew once

Relativity flew its 3D-printed Terran 1 a single time, on March 23, 2023. The rocket passed max-q, the point of peak aerodynamic stress, then lost its upper stage and never made orbit. A month later the company retired the small launcher to concentrate on the larger, reusable Terran R.

Terran R is a medium-class rocket roughly in the Falcon 9 weight class, with a first flight Relativity has slated for late 2026 from Cape Canaveral. Industry sources expect that to slip to 2027, a delay consistent with the development pace of nearly every new orbital-class launcher of the past decade.

The Mars orbiter would be Terran R’s interplanetary debut. If the rocket flies close to schedule, the 2028 transfer window to Mars is reachable. If it slips, the mission slips with it. There is no version of this where the orbiter beats the rocket to the pad.

What the orbiter would carry

The science payload comes from NASA’s Ames Research Center, which will design, build, and integrate it. The centerpiece is an atmospheric suite NASA calls Aeolus — four instruments meant to deliver the first integrated, daily, global picture of Martian winds, temperatures, dust, and clouds. A radar instrument would map subsurface ice and geology, the kind of water-resource data future crewed missions would lean on.

NASA says it will operate the instruments for at least one Martian year and build the pipeline that turns raw readings into usable science, under what it describes as its first six-year reimbursable Space Act Agreement. Relativity builds, owns, and flies the spacecraft; NASA supplies the instruments and the data processing.

Then there is the relay. The orbiter is being pitched to carry high-bandwidth laser and radio links back to Earth plus radio communications with surface assets. That matters because NASA’s working Mars relay fleet — the Mars Reconnaissance Orbiter, MAVEN, and Odyssey — is aging, with no committed replacement for the data backhaul every Mars rover depends on. A privately built relay arriving in the late 2020s would fill a hole the agency has openly worried about.

Relativity has said all of the mission’s scientific data will be released publicly. The control questions are harder. Who sets the relay schedule when multiple surface assets compete for the same downlink? What happens to a publicly funded rover if a privately owned orbiter becomes the only way to hear from it? Those answers are not in the announcement.

The Schmidt factor

The mission is inseparable from Eric Schmidt. The former Google chief executive took a controlling stake and became CEO of a cash-strained Relativity in March 2025, succeeding co-founder Tim Ellis. He arrived with money and with a network of science philanthropists.

Schmidt has framed the company’s goal as making access to space routine and pushing science beyond Earth, describing the Interplanetary Sciences Program as a step built on the Terran R platform. The orbiter is meant as a proof of concept; Relativity has not detailed the missions that would follow.

It is also not the only Schmidt-adjacent payload on Terran R’s manifest. Schmidt Sciences, the philanthropic vehicle Schmidt founded with his wife Wendy, announced in January 2026 the Eric and Wendy Schmidt Observatory System. That suite includes Lazuli, a space telescope with a primary mirror larger than Hubble’s, also targeting a launch as soon as 2028 on Terran R.

Two flagship science missions, one unflown rocket, one fortune behind much of both. Whether Schmidt Sciences is the Mars orbiter’s specific backer is unconfirmed; the company will only say the funder is philanthropic.

A privately funded mission to Mars

Privately backed science is not new in itself. The Breakthrough Initiatives funded ground-based SETI work. Jared Isaacman — now NASA’s administrator — bankrolled human spaceflight before taking the job. What is new in the Relativity model is the scale of capital a Mars orbiter requires, the presence of NASA instruments aboard a privately owned spacecraft, and the folding of commercial communications into what has historically been sovereign infrastructure.

This is also not Relativity’s first private Mars plan. In 2022 the company and Impulse Space announced a Mars lander to fly on Terran R, originally targeting the 2024 window; a 2023 update pushed it to as soon as 2026, and neither company has said much about it since.

The 2028 window is getting crowded regardless. SpaceX continues to pitch Starship cargo flights to Mars in roughly the same period, without firm payload commitments. More privately developed hardware may be pointed at the planet in 2028 than at any prior window. Whether all of it actually flies is a separate question, and Mars schedules are famously elastic.

The credibility test

Relativity’s announcement lands at an awkward point in its own story. It still has to prove Terran R can reach orbit. It has to prove the rocket can be reused on a useful cadence. And it has to show a launch company can build, integrate, and operate a deep-space science platform — a different engineering discipline entirely.

Plenty of launch startups have promised spacecraft alongside their rockets; few delivered both. The ones that came closest — SpaceX with Dragon, Rocket Lab with its Photon bus — got there through years of incremental flight experience Relativity does not yet have. The Mars orbiter would compress that curve dramatically, or expose how steep it still is.

The schedule offers no slack. If the program slips by a single Mars window, 26 months, the orbiter becomes a 2030 or 2031 mission, and the case for it shifts with it.

For now the orbiter is instrument designs at Ames, tank hardware in a Long Beach factory, and a 2028 launch window that, like every Mars window, opens and closes on the planet’s schedule rather than anyone’s. The rocket meant to carry it has still never left the pad. Both have to work, roughly two years apart, and Mars does not hold the window open.

The post In June 2026, Relativity Space — the rocket company Eric Schmidt took over in 2025, whose one rocket has never reached orbit — said it would privately build and fly a Mars orbiter in 2028, carrying NASA’s Aeolus atmospheric instruments and doubling as a communications relay, paid for by a philanthropic backer it has not named appeared first on Space Daily.

Around 66 million years ago, an asteroid wiped out 75% of the species on Earth. This event caused the extinction of all dinosaurs except birds, referred to as non-avian dinosaurs. However, an open question in paleontology is whether the dinosaurs were already declining before the asteroid hit. Many scientists think that around 5 to 10 million years before the extinction event, dinosaurs became less biologically diverse across America, making them more prone to extinction. 

To investigate this hypothesis, scientists recently revisited fossils in a rock layer from the end of the dinosaur era that previous researchers had incorrectly dated. The bulk of the fossils from this period had previously been collected from a different section of rocks called the Hell Creek Formation in Montana. These researchers studied a rock layer in New Mexico that is exposed to the surface, known as the Naashoibito Member. It’s approximately 30 meters (about 100 feet) thick and formed from ancient river sediments. 

To determine when the Naashoibito Member formed, the scientists measured the decay of radioactive elements within its mineral grains over time, a technique called radiometric dating. The scientist reasoned that these mineral grains must have crystallized before being transported and incorporated into the Naashoibito Member, so their youngest ages should provide a maximum depositional age. 

They determined the ages of 1,046 crystals of the mineral feldspar from 2 dinosaur-bearing rock layers in the Naashoibito Member. Based on these ages, the researchers found that a sandstone within 5 meters (about 16 feet) of the lowest boundary of the Naashoibito Member must be younger than 66.9 million years old. They found that the other layer, which is around 3.5 meters (11 feet) from the base of the lowest boundary, must be younger than 66.4 million years old. These age ranges indicated that the sandstone contains dinosaur fossils formed 400,000 years before their extinction.

Next, the researchers measured the direction of magnetic minerals inside the rocks, using a practice called magnetostratigraphy. The direction of these minerals indicates where Earth’s magnetic field was pointing at that time. Scientists have shown that the Earth’s magnetic field has flipped multiple times over Earth’s history, so they can use these magnetic signals to create a timescale for when the sediments formed. 

The researchers wanted to determine whether the magnetic minerals were lined up in a direction like today, called normal polarity, or the opposite, called reverse polarity. The researchers found one rock layer with normal polarity at the base of the Naashoibito Member, and one with reverse polarity in the upper part of the Naashoibito Member. These magnetic field directions lined up with 2 known polarity intervals over a timeline that matched the feldspar dates. Together, these data demonstrated that the Naashoibito Member formed at the end of the dinosaur era, around the same time as the Hell Creek Formation.

Next, the researchers wanted to test whether non-avian dinosaurs maintained their diversity across different regions of Western North America during this time period. They compared fossil patterns from locations across North America using statistical grouping methods that determine how similar or different their environments were. They found that temperature, rather than geographical location alone, was the best predictor of diversity at the extinction event. 

The team concluded that a diverse population of Naashoibito dinosaurs lived at around the same time as the Hell Creek dinosaurs. Earlier scientists surmised that dinosaurs were already on the decline because they studied the colder northern regions, where diversity was lower. However, these results suggest that warmer conditions in the south still supported diverse dinosaur populations. Together, this evidence suggests that dinosaurs were still diverse and thriving 66 million years ago, and that their extinction was indeed a result of the asteroid impact.

The post Were dinosaurs doomed before the asteroid hit? appeared first on Sciworthy.

The oldest solid material ever identified on Earth did not form on Earth, or anywhere near it. It came down inside a meteorite that fell near the town of Murchison, in country Victoria, on a spring morning in 1969. Sealed in that rock were microscopic grains of stardust, and the oldest of them formed roughly 7 billion years ago, well before the Sun.

The claim is accurate, with one detail worth keeping straight: 7 billion years is the age of the oldest grains, not of all of them.

The meteorite

At about 11 in the morning on 28 September 1969, people around Murchison heard a series of booms and saw a fireball trailing smoke across the sky. Fragments came down over several square kilometres, and more than 100 kilograms were eventually collected.

The rock is a carbonaceous chondrite, a primitive type rich in carbon compounds, and because the fall was witnessed and the material gathered quickly, Murchison became one of the most studied meteorites in the world. The grains that matter here are tiny pieces of silicon carbide, far smaller than a grain of sand, recovered by dissolving the surrounding rock in acid until only the most durable specks remain.

How you date a grain older than the Sun

These specks are not dated the way a rock on Earth is. They are dated by how long they drifted through space.

Before they were swept into the cloud that became our solar system, the grains spent a very long time as free-floating interstellar dust. Out there they were exposed to galactic cosmic rays, high-energy particles that strike solid matter and, now and then, transform an atom inside it into a new isotope. One of those products, a form of neon, builds up at a roughly steady rate. Measure how much has accumulated, and you can work out how long the grain was adrift before it was sheltered inside the meteorite.

That is the method a team led by Philipp Heck of the Field Museum and the University of Chicago used in a study published in 2020. They measured cosmic-ray exposure ages for 40 large presolar silicon carbide grains from Murchison, the largest such dating effort of its kind.

Most are old, and the oldest are very old

This is where the precision matters. Most of the grains the team dated formed in the few hundred million years before the Sun, clustering around 4.6 to 4.9 billion years ago. A smaller number were older. The oldest reached about 7 billion years, roughly 2.5 billion years beyond the 4.54-billion-year age of Earth and the solar system.

So the headline figure is the extreme of the range, not the average. Even the youngest of these grains, though, still predates the Sun, which is what makes the whole population presolar. They are older than the star our planet orbits.

What the grains actually are

Each grain is a piece of another star.

Silicon carbide of this kind condenses in the cooling outflows of dying stars, the kind that puff their outer layers into space late in life. Those expelled grains travel the galaxy until some are caught up in the formation of a new system, which is how a fragment of a star that died before the Sun ended up in a paddock in Victoria.

The clustering of ages led Heck’s team to a further suggestion, offered as interpretation rather than settled fact: that many of the grains may have formed during a burst of star formation in the galaxy around 7 billion years ago, a busier-than-usual stretch of stellar birth and death. That reading is debated, and the dating itself does not depend on it.

What is not in question is the simpler thing. A rock that fell on an Australian farming town within living memory carried, intact, solid matter that is older than the Sun, the Earth, and everything else ever measured on this planet. It had been drifting for billions of years before there was a planet here to land on.

The post The oldest solid material ever found on Earth didn’t come from Earth at all — it was locked inside a meteorite that landed near Murchison, Victoria in 1969, and the stardust grains inside formed roughly 7 billion years ago, before the Sun existed. appeared first on Space Daily.

Standing for Reform against Ed Davey's wife in a Lib Dem heartland, Chris Larkin found shy supporters, hostile middle-class lecturers and an unexpected guardian angel in a tower block.

The post My Kamikaze Attempt to Beat Ed Davey’s Wife in the Local Elections as a Reform Candidate appeared first on The Daily Sceptic.