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Is it an asteroid or comet? This strange solar system object is actually both. – Space.com

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Scientists have identified a rare solar system object with traits of both an asteroid and a comet.

The object, dubbed 2005 QN173, orbits like any other asteroid, but most such objects are rocks that don’t change much as they loop through the solar system. Not so for 2005 QN173, which was first spotted in 2005 (hence the name), according to new research. Instead, it looks like a comet, shedding dust as it travels and sporting a long, thin tail, which suggests that it’s covered with icy material vaporizing away into space — even though comets usually follow elliptical paths that regularly approach and retreat from the sun.

“It fits the physical definitions of a comet, in that it is likely icy and is ejecting dust into space, even though it also has the orbit of an asteroid,” Henry Hsieh, lead author of the new research and a planetary scientist at the Planetary Science Institute, said in a statement. “This duality and blurring of the boundary between what were previously thought to be two completely separate types of objects — asteroids and comets — is a key part of what makes these objects so interesting.” 

Related: The ‘megacomet’ Bernardinelli-Bernstein is the find of a decade. Here’s the discovery explained.

Despite its comet-like characteristics, the object’s orbit is definitely that of an asteroid: It quietly loops around the sun in the outer portion of the asteroid belt that falls between Mars and Jupiter, circling once every 5 years or so.

But this summer, astronomers looking through data gathered by the Asteroid Terrestrial-Impact Last Alert System (ATLAS) survey in Hawaii on July 7 noticed that the object was sporting a tail. The feature showed up in additional observations made by a telescope at Lowell Observatory in Arizona. Scientists then checked previous observations made by other facilities, and spotted the tail again in images gathered on June 11 by the Zwicky Transient Facility in California.

In those observations, the object was heading away from the sun, having made its closest approach, or perihelion, on May 14. (While a comet’s close approach is much more dramatic than that of a typical asteroid in the main belt, all objects orbiting the sun move closer and farther away from it over the course of an orbit. Earth’s perihelion, for example, falls in early January.)

Meanwhile, other scientists looked through observations of 2005 QN173 gathered by the Dark Energy Camera in July 2016, the last time the object was around perihelion — and lo and behold, here too they spotted a tail.

Activity around perihelion matches the profile of a comet: increasing heat from the sun turns frozen ice into gas, a process called sublimation. Typical comets spend most of their time far enough away from the sun for activity to be frozen — literally.

“Most comets are found to come from the cold outer solar system, beyond the orbit of Neptune, and spend most of their time there, with their highly elongated orbits only bringing them close to the sun and the Earth for short periods at a time,” Hsieh said. “During those times when they are close enough to the sun, they heat up and release gas and dust as a result of ice sublimation, producing the fuzzy appearance and often spectacular tails associated with comets.” 

Of the half a million objects scientists have examined in the asteroid belt, this is the eighth one that scientists have been able to confirm has been active multiple times, and it’s one of only 20 suspected “main-belt comets.”

The new research included old observations dug out of the archives of various instruments originally gathered between 2004 and 2020 at times when the comet wasn’t active, in order to better understand the object itself. Those observations suggest that the nucleus or head of the comet is about 2 miles (3.2 kilometers) wide, according to the statement.

Then, the scientists incorporated fresh observations of the object made by a host of instruments this July and August aimed at better understanding the activity of the strange main-belt comet. In particular, the researchers were able to measure the object’s tail, which in July stretched 450,000 miles (720,000 kilometers) long, a little less than twice the distance from Earth to the moon.

But despite its massive length, the tail isn’t all that wide, which poses the scientists a new puzzle.

“This extremely narrow tail tells us that dust particles are barely floating off of the nucleus at extremely slow speeds and that the flow of gas escaping from the comet that normally lifts dust off into space from a comet is extremely weak,” Hsieh said. 

“Such slow speeds would normally make it difficult for dust to escape from the gravity of the nucleus itself, so this suggests that something else might be helping the dust to escape,” Hsieh added. One explanation could be that the nucleus is spinning so quickly that it shoots extra dust into space, but the scientists don’t have enough observations to be sure.

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The scientists are marking their calendars for February 2026, when the object can be seen from the Southern Hemisphere and also reaches the distance from the sun at which it may become active again.

The research is described in a paper accepted to The Astrophysical Journal Letters and available to read as a pre-print on arXiv.org; the research was also presented on Monday (Oct. 4) at the American Astronomical Society’s Division for Planetary Sciences conference being held virtually this week.

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

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Guilt, grief and anxiety as young people fear for climate’s future

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Overwhelmed, sad, guilty are some of the emotions young people say they feel when they think of  Climate Change and their concerns world leaders will fail to tackle it.

Broadly referred to as climate anxiety, research has stacked up to measure its prevalence ahead of the U.N. talks in Glasgow, which begin at the end of the month to thrash out how to put the 2015 Paris Agreement on curbing climate change into effect.

One of the biggest studies to date, funded by Avaaz, an online campaign network, and led by Britain’s University of Bath, surveyed 10,000 young people aged 16-25 years in 10 countries. It published its results in September.

It found around three quarters of those surveyed considered the future frightening, while a lack of action by governments and industry left 45% experiencing climate anxiety and distress that affected their daily lives and functioning.

Elouise Mayall, an ecology student at Britain’s University of East Anglia and member of the UK Youth Climate Coalition, told Reuters she had felt guilty and overwhelmed.

“What I’d be left with is maybe the sense of shame, like, ‘how dare you still want lovely things when the world is ending and you don’t even know if you’re going to have a safe world to grow old in’.”

She spoke of conflicting emotions.

“You might have sadness, there might be fear, there might be a kind of overwhelm,” she said. “And maybe even sometimes a quite like wild optimism.”

Caroline Hickman, a psychotherapist and lecturer at the University of Bath and one of the co-authors of the research published in September, is working to help young people manage climate-related emotions.

“They’re growing up with the grief and the fear and the anxiety about the future,” she told Reuters.

“SENSE OF MEANING”

London-based psychiatrist Alastair Santhouse sees climate change, as well as COVID-19, as potentially adding to the burden, especially for those pre-disposed to  anxiety .

For now, climate anxiety alone does not normally require psychiatric help. Painful as it is, it can be positive, provided it does not get out of control.

“Some anxiety about climate change is motivating. It’s just a question of how much anxiety is motivating and how much is unacceptable,” said Santhouse, author of a book that tackles how health services struggle to cope with complex mental issues.

“The worry is that as climate change sets in, there will be a more clear cut mental health impact,” he added.

Among some of the world’s communities that are already the most vulnerable, extreme weather events can also cause problems such as post traumatic stress disorder.

Leading climate campaigner Greta Thunberg, 18, has experienced severe climate anxiety.

“It’s a quite natural response, because, as you see, as the world is today, that no one seems to care about what’s happening, I think it’s only human to feel that way,” she said.

For now, however, she is hopeful because she is doing everything she possibly can.

“When you take action, you also get a sense of meaning that something is happening. If you want to get rid of that anxiety, you can take action against it,” she said.

 

(Reporting by Barbara Lewis; Editing by Alison Williams)

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Rocket failure mars U.S. hypersonic weapon test as others succeed

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The Pentagon ‘s hypersonic weapon programs suffered a setback on Thursday when a booster rocket carrying a hypersonic weapon failed, people briefed on the test result said.

The test was intended to validate aspects of one of the Pentagon’s hypersonic glide vehicles in development, two of the people said.

Hypersonic glide vehicles are launched from a rocket in the upper atmosphere before gliding to a target at speeds of more than five times the speed of sound, or about 3,853 miles (6,200 kilometers) per hour.

In a separate series of tests conducted on Wednesday, the U.S. Navy and Army tested hypersonic weapon component prototypes. That test successfully “demonstrated advanced hypersonic technologies, capabilities, and prototype systems in a realistic operating environment,” the Pentagon said in a statement.

The United States and its global rivals have quickened their pace to build hypersonic weapons – the next generation of arms that rob adversaries of reaction time and traditional defeat mechanisms.

U.S. President Joe Biden expressed concern on Wednesday about Chinese hypersonic missiles, days after a media report that Beijing had tested a nuclear-capable hypersonic glide weapon.

Glide bodies are different from their air-breathing hypersonic weapon cousins which use scramjet engine technology and the vehicle’s high speed to forcibly compress incoming air before combustion to enable sustained flight at hypersonic speeds. An air-breathing hypersonic weapon was successfully tested in September.

Companies such as Lockheed Martin and Raytheon Technologies are working to develop the hypersonic weapon capability for the United States.

(Reporting by Mike Stone and Idrees Ali in Washington; Editing by Sandra Maler)

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Patagonian fossils show Jurassic dinosaur had the herd mentality | Saltwire – SaltWire Network

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By Will Dunham

(Reuters) – A vast trove of fossils unearthed in Argentina’s southern Patagonia region is offering the oldest-known evidence that some dinosaurs thrived in a complex and well-organized herd structure, with adults caring for the young and sharing a communal nesting ground.

Scientists said on Thursday the fossils include more than 100 dinosaur eggs and the bones of about 80 juveniles and adults of a Jurassic Period plant-eating species called Mussaurus patagonicus, including 20 remarkably complete skeletons. The animals experienced a mass-death event, probably caused by a drought, and their bodies were subsequently buried by wind-blown dust, the researchers said.

“It is a pretty dramatic scene from 193 million years ago that was frozen in time,” said paleontologist Diego Pol of the Egidio Feruglio Paleontological Museum in Trelew, Argentina, who led the research published in the journal Scientific Reports.

Mussaurus, which grew to about 20 feet (6 meters) long and about 1.5 tons, possessed a long neck and tail, with a small head. It was bipedal as an adult but newborns were quadrupedal. Mussaurus lived early in the Jurassic, the second of three periods comprising the age of dinosaurs. It was a relatively large beast for its time – much bigger than contemporaneous meat-eating dinosaurs. Dinosaurs became true giants later in the Jurassic.

“The site is one of a kind,” Pol said. “It preserves a dinosaur nesting ground including delicate and tiny dinosaur skeletons as well as eggs with embryos inside. The specimens we have found showed that herd behavior was present in long-necked dinosaurs since their early history. These were social animals, and we think this may be an important factor to explain their success.”

The animals were found to have been grouped by age at the time of their deaths, with hatchlings and eggs in one area while skeletons of juveniles were clustered nearby. The eggs were arranged in layers within trenches. Adults were found alone or in pairs.

This phenomenon, called “age segregation,” signals a complex social structure, the researchers said, including adults that foraged for meals and cared for the young. The researchers suspect that members of the herd returned to the same spot during successive seasons to form breeding colonies.

“The young were staying with the adults at least until they reached adulthood. It could be that they stayed in the same herd after reaching adulthood, but we don’t have information to corroborate that hypothesis,” said paleontologist and study co-author Vincent Fernandez of the Natural History Museum in London.

Herd behavior also can protect young and vulnerable individuals from attack by predators.

“It’s a strategy for the survival of a species,” Fernandez said.

The oldest previous evidence for dinosaur herd behavior was from about 150 million years ago.

The nesting ground was situated on the dry margins of a lake featuring ferns and conifers in a warm but seasonal climate. The eggs are about the size of a chicken’s, and the skeleton of a hatchling fits in the palm of a human hand. The adults got as heavy as a hippo.

A scanning method called high-resolution X-ray computed tomography confirmed that the embryos inside the eggs indeed were of Mussaurus.

Mussaurus was a type of dinosaur called a sauropodomorph, which represented the first great success story among herbivorous dinosaurs. Sauropodomorphs were an evolutionary forerunner to a group called sauropods known for long necks and tails and four pillar-like legs.

The largest land animals in Earth’s history were the sauropod successors of sauropodomorphs, as exemplified by a later denizen of Patagonia called Argentinosaurus that reached perhaps 118 feet (36 meters) in length and upwards of 70 tons.

(Reporting by Will Dunham in Washington, Editing by Rosalba O’Brien)

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