Month: June 2023

[This German lady scientist is interesting. Jan]

Here’s the video: https://www.youtube.com/watch?v=9-jIplX6Wjw

[There were a LOT of nuclear tests in America, on American soil, mostly in Nevada. There have been all kinds of nuclear tests, in the air, at sea, in space, underground, etc. Scientists, especially American scientists, tested and measured nuclear explosions under every conceivable kind of condition. In the final years, underground nuclear testing was the most common and safe way to do it. Atmospheric tests were the most dangerous because of winds. Jan]

Here’s the video: https://www.youtube.com/watch?v=FCf_yEoLj9o

[This topic is nasty but belongs in the field of human science. I have been following, out of pure curiosity the nightmare problem of the 5 people in the tiny submarine that went down to the Titanic and they are now lost on the sea bed. I had just pondered their fate. I thought at first that the most likely scenario is that maybe the submarine imploded and they all just died. From every angle, human survival in this case is IMPOSSIBLE. I looked at this as done and dusted, these people died. Regardless of what happened, they are DEAD. The thing that piqued my interest was that sonars were picking up tapping noises every 30 minutes which sounded like people trapped in the submarine knocking on it so that they could be found. There are many safety issues with the submarine like: Why didn't they have some cheap transponders on it which send out messages that are easy to find. That, for example, is a very simple, and very effective solution. But, that clearly was not done. The tapping noises were heard yesterday and last night. So it seems as if these people are genuinely alive. The temperature down there is extremely cold. So I thought that between the cold and oxygen deprivation they WILL DIE. There is ZERO HOPE. Then I wondered if some would not die before others? What if some die and others can then continue breathing oxygen? I must say, I had thought that the final outcome of this is that it may take them days, weeks or months, or longer to eventually find the submarine and they'll open it and it will be a forensic coffin and a year or more from now we'll find out how long they lived and when they died. But check out what a doctor and an admiral have to say. This is quite bizarre and it is how the human body adapts! Jan]

It is a claustrophobic, terrifying prospect – being trapped in a 22ft submersible, potentially thousands of feet underwater, with oxygen running out.

The exact whereabouts of the Titanic submersible and the condition of the five crew onboard are unknown. It is thought that, if the vessel is still intact, it may have just a few hours of oxygen remaining, creating a race against time to find the sub before it is too late.

However, that timeline is not necessarily rigid. Dr Ken LeDez, a hyperbaric medicine expert at Memorial University in St John’s, Newfoundland, has told BBC News that, depending on conditions, some of those aboard could survive longer than expected.

"It depends on how cold they get and how effective they are at conserving oxygen," he said, adding that shivering will use up a lot of oxygen, while wrapping up in a huddle can help to conserve heat.

He said running out of oxygen is a gradual process. "It’s not like switching off a light, it’s like climbing a mountain – as the temperature gets colder and metabolism falls [it depends] how fast you ascend that mountain," he said.

While admitting that we do not know the full situation inside the submersible, Dr LeDez said conditions could be different person-to-person, and that although it is a "disturbing conversation", some could survive longer than others.

On Wednesday, Rear Admiral John Mauger from the US Coast Guard said there were a number of unknowns in the search and rescue mission.

"We do not know the rate of consumption of oxygen per occupant on the sub," Rear Adm Mauger told the BBC.

Dr LeDez also said that running out of oxygen is not the only danger those on board face.

The vessel may have lost electrical power, which is likely to have a role in controlling the amount of oxygen and carbon dioxide inside the vessel.

As the oxygen level falls, the proportion of carbon dioxide being breathed out by the crew will be rising, with potentially fatal consequences.

"As levels of carbon dioxide build up, then it becomes sedative, it becomes like an anaesthetic gas, and you will go to sleep."

Too much of the gas in a person’s bloodstream, known as hypercapnia, can kill them if not treated.

Former Royal Navy submarine captain Ryan Ramsey says he looked at videos online of the inside of Titan and could not see a carbon dioxide removal system, known as scrubbers.

"That for me is the greatest problem of all of them," he says.
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At the same time, the crew are at risk from hypothermia, where the body gets too cold.

According to Capt Ramsey, if the sub is on the seabed, the water temperature will be about 0C. If it has also lost electricity, it will not be generating any power and therefore cannot generate heat.

But hypothermia "could be their friend", said Dr LeDez.

"There is a possibility if they cool down enough and lose consciousness they could live through it – rescuers know this," he said, adding that the body will automatically try to adapt to survive.

However on the flip side, hypothermia, the lack of oxygen and the build-up of carbon dioxide within the sub mean the crew’s ability to make contact with the search and rescue mission, such as by banging on the hull at regular intervals to try and attract attention, will dwindle.

"If they’re unconscious, they’re not going to be able to do much to help themselves," says Dr LeDez.

While the Coast Guard has warned there is probably little oxygen left, the crew may be able to conserve their supplies – at least for a while.

Mr Ramsey says slowing their breathing would also help but admits this could be difficult considering the stress they would be under.

Dr LeDez says they could also spread out carbon dioxide-absorbing granules or reduce their power use if they still have electricity.

In terms of food and water, the Coast Guard said the crew had some "limited rations" on board but couldn’t say how much.

Despite all these challenges, Dr LeDez urges against cancelling the search-and-rescue operation too soon, saying they might be able to survive even when oxygen levels are very low.

"If anybody can survive in it, you know, it’s these individuals," he says. "It just depends on them having power and depends on them having light to be able to find things and make these controls, but absolutely, they could still be alive."

Source: https://www.bbc.com/news/world-us-canada-65981277

[This makes sense. I did look into the effects of the mass of ice accumulating at the poles in the past, and how that could cause the Earth to tilt. So this is not surprising. We live on a very fragile planet and our biology is very soft. Whites are the only race who can actually help to keep this planet going and who could survive anything. Jan]

Earth’s tilt has changed by 31.5 inches (80 centimeters) between 1993 and 2010 because of the amount of groundwater humans have pumped from the planet’s interior.

In that period, humans removed 2,150 gigatons of water from natural reservoirs in the planet’s crust. If such an amount was poured into the global ocean, its surface would rise by 0.24 inches (6 millimeters). A new study has now revealed that displacing such an enormous amount of water has had an effect on the axis around which the planet spins.

Scientists arrived at this conclusion by modeling the changes in the position of Earth’s rotational pole, the point at which the planet’s imaginary axis would stick out of the surface if it were a physical object. The position of the rotational pole is not identical with the geographical north and south poles and actually changes over time, so the rotational axis cuts through different spots on the planet’s crust at various points in time.

Since 2016, scientists have known that the rotational pole is affected by climate-related processes, such as the thawing of icebergs and the redistribution of the mass of the water locked in them. But until the researchers added the pumped-out water into their models, the results hadn’t perfectly matched observations. Without the pumped-out groundwater, the model was off by 31 inches (78.5 centimeters).

"Earth’s rotational pole actually changes a lot," Ki-Weon Seo, a geophysicist at Seoul National University who led the study, said in a statement. "Our study shows that among climate-related causes, the redistribution of groundwater actually has the largest impact on the drift of the rotational pole."

Since the tilt of Earth’s axis can have an effect on seasonal weather on the planet’s surface, scientists now wonder whether the shifts of the rotational pole could contribute to climate change in the long-term.

"Observing changes in Earth’s rotational pole is useful for understanding continent-scale water storage variations," Seo said. "Polar motion data are available from as early as the late 19th century. So, we can potentially use those data to understand continental water storage variations during the last 100 years. Were there any hydrological regime changes resulting from the warming climate? Polar motion could hold the answer."

Overall, the Earth’s rotational pole shifts by several meters a year. How much drained groundwater reservoirs contribute to this shift depends on where on the planet they are located. The study showed that water removed from mid-latitudes has the largest effect on the planet’s tilt.

Managing how groundwater moves around the globe could therefore help limit the shifts of the rotational pole and thus the potential climate effects that come with them.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community.

Source: https://www.space.com/earth-tilt-changed-by-groundwater-pumping

[This is the nastiest event that has taken place in a long time. It is the worst thing that has happened on the planet in HUNDREDS of years. It happened in Russia in 1908. Jan]

Here’s the video: https://www.youtube.com/watch?v=qhVvihYJBEs

[What is really interesting in this article is that these scientists studied the growth of CITIES and that cities WILL COLLAPSE! This is something I did not know about. I would otherwise not take this idea too seriously. I have been looking into this topic about life in the universe, and the answer is actually much scarier. As bizarre as it sounds, we might be alone – and that might be a very good thing! I will discuss this later. Jan]

Why has humanity never been visited by aliens (that we know of)? The question has confounded scientists for decades, but two researchers have come up with a possible — and disturbing — explanation: Advanced civilizations could be doomed to either stagnate or die before they get the chance.

The new hypothesis suggests that, as space-faring civilizations grow in scale and technological development, they eventually reach a crisis point where innovation no longer keeps up with the demand for energy. What comes next is collapse. The only alternative path is to reject a model of "unyielding growth" in favor of maintaining equilibrium, but at the cost of a civilization’s ability to expand across the stars, the researchers said.

The argument, published on May 4 in the journal Royal Society Open Science, attempts to find a resolution to the Fermi Paradox. Taking its name from the casual lunchtime musings of Nobel Prize-winning physicist Enrico Fermi, the paradox draws attention to the contradiction between the immense scope and age of the universe — two things that suggest the universe should be teeming with advanced alien life — and the lack of evidence that extraterrestrials exist anywhere in sight. "So where is everybody?" Fermi is thought to have remarked.

The researchers of the new study say they may have the answer.

"Civilizations either collapse from burnout or redirect themselves to prioritizing homeostasis, a state where cosmic expansion is no longer a goal, making them difficult to detect remotely," astrobiologists Michael Wong, of the Carnegie Institution for Science, and Stuart Bartlett, of the California Institute of Technology, wrote in the study. "Either outcome — homeostatic awakening or civilization collapse — would be consistent with the observed absence of [galactic-wide] civilizations."

The pair came to their hypothesis by researching studies of the "’superlinear"’ growth of cities. These studies suggested that cities increase in size and energy consumption at an exponential rate as their populations grow, inevitably leading to crisis points — or singularities — that cause rapid crashes in growth, followed by an even more precipitous, potentially civilization-ending, collapse.

"We hypothesize that once a planetary civilization transitions into a state that can be described as one virtually connected global city, it will face an ‘asymptotic burnout,’ an ultimate crisis where the singularity-interval time scale becomes smaller than the time scale of innovation," they wrote.

These close-to-collapse civilizations would be the easiest for humanity to detect, the researchers suggest, as they would be dissipating large amounts of energy in a "wildly unsustainable" way. "This presents the possibility that a good many of humanity’s initial detections of extraterrestrial life may be of the intelligent, though not yet wise, kind," the researchers wrote.

To avert their doom, civilizations could undergo a "homeostatic awakening," redirecting their production away from unbounded growth across the stars to one that prioritizes societal wellbeing, sustainable and equitable development and harmony with their environment, the researchers suggest. While such civilizations may not completely abandon space exploration, they would not expand on scales great enough to make contact with Earth likely.

The researchers point to a few of humanity’s "mini-awakenings" that addressed global crises on Earth, such as the reduction of global nuclear arms stockpiles from 70,000 warheads to below 14,000; the halting of the once-growing hole in Earth’s ozone layer by banning chlorofluorocarbon emissions; and the 1982 international whaling moratorium.

The scientists stress, however, that their suggestion is simply a hypothesis, taken from the observation of laws that seem to govern life on Earth, and is designed to "provoke discussion, introspection and future work."

Their proposal joins a bountiful crop of other scientific and popular suggestions as to why we’ve never made direct contact with celestial visitors. These include the numerous practical challenges presented by interstellar travel; that aliens may actually be visiting in secret; or that aliens arrived to Earth too soon (or humans too early) in the life of the universe for direct contact.

Another hypothesis, published April 4 in The Astrophysics Journal, suggests that the sheer scale of the universe means it could take as long as 400,000 years for a signal sent by one advanced species to be received by another — a timescale that’s far greater than the brief period humans have been able to scan the skies.

Source: https://www.livescience.com/alien-civilizations-doomed-to-collapse

[The question is more tricky than you might realise. Jan]

To the naked eye, the night sky reveals only one moon. But how many moons have ever orbited Earth?

How many moons does Earth have? The answer seems obvious: Earth has only one moon. It’s even in the name: the moon. At first, Earth’s moon needed no other name, because for millennia, we didn’t know any other natural satellite existed. But over centuries of astronomy and space exploration, we’ve discovered hundreds of moons in the solar system, and there may be more than you think circling our planet.

"The moon" holds the title of Earth’s only solid, permanent moon, said Gábor Horváth, an astronomer at Eötvös Loránd University in Hungary. But it’s not the only object to be pulled into Earth’s orbit; a host of near-Earth objects and dust clouds are also caught in Earth’s gravity. These often-temporary satellites technically qualify as minimoons, quasi-satellites or ghost moons.

So the question of how many moons Earth has is more complicated than you might think. The number has changed over time — from zero, to one, to sometimes multiple moons.

Back in Earth’s early days, about 4.5 billion years ago, our planet was moonless. Then, around 4.4 billion years ago, a Mars-size protoplanet called Theia struck Earth. Large chunks of Earth’s crust were catapulted into space. The rocky debris came together — maybe in just a few hours — to form the moon, according to 2022 research published in The Astrophysical Journal Letters.

Other "moons" that measure just a few feet across have been far more temporary, captured by Earth’s gravity for short periods before escaping back into space. In 2006, there was the up-to-20-foot-wide (6 meters) asteroid 2006 RH120, a space rock that lingered for 18 months and was the first observed long-term capture of an asteroid into Earth’s orbit. And 2020 CD3, a space rock up to 11.5 feet (3.5 m) across, left Earth’s orbit in March 2020 after spending three years as our mini second moon. In 2020, scientists also spotted SO 2020, a minimoon that drifted back into space in early 2021. Turns out, though, that SO 2020 wasn’t a natural moon; it was the remains of a rocket booster from the 1960s.

An example of a recent minimoon was a space rock up to 11.5 feet (3.5 m) across known as 2020 CD3 which was in Earth’s orbit for three years before leaving.

For 13 hours in 2015, scientists thought they had found a new temporary moon orbiting Earth. But they quickly realized their mistake when it was revealed that the "moon" was merely the European Space Agency’s Gaia space telescope, prompting the International Astronomical Union’s Minor Planet Center to issue a retraction.

In addition to the moons that come and go from Earth’s orbit, there are space objects that NASA calls quasi-satellites, such as the asteroid 3753 Cruithne. These space rocks orbit the sun so similarly to Earth that they stick with our planet throughout its 365-day orbit. The quasi-moon Kamo’oalewa — suspected of being an artifact of the actual moon — is driven primarily by the sun’s gravity but appears to orbit Earth in a corkscrew-like path.

Some space objects, such as asteroid 2010 TK7, earn the title of "moon" because they get caught in the unique gravity of the sun-Earth or Earth-moon systems. The gravity of the two larger bodies creates regions of centripetal force, called Lagrange points, that hold smaller objects in place in gravitationally stable points in space, according to NASA. Two Lagrange points, L4 and L5, form an equilateral triangle with Earth. Effectively, the objects captured in these Lagrange points, called Trojans, fall in line with Earth and join its orbit around the sun.

"Parallel to the formation of the solid Moon and stabilization of its orbit around the Earth, the Lagrange points L4 and L5 have also arisen, and have started to collect [and] trap the interplanetary dust particles," Horváth told Live Science in an email. Some astronomers call these particle clouds "ghost moons." They’re also called Kordylewski clouds, after the Polish astronomer who first reported them in the 1960s. At first, many scientists were unconvinced, but since then, research by astronomers such as Horváth has confirmed that dust clouds are accumulating at these Lagrange points.

However, these ghost moons will never form a more solid moon, because the dust can’t conglutinate, or join or adhere together, Horváth said. And while the Lagrange points remain constant, the material in them is dynamic, constantly entering and exiting the dust cloud.

Source: https://www.livescience.com/how-many-moons-does-earth-have

[I don't know how common quakes are on other planets and moons. I know the moon experiences some kind of Moon Quakes. But I think that quakes on Earth are much bigger than anything you see on other planets. Plate Tectonics and the movement of continents is UNIQUE to Earth, and it's actually very weird. Jan]

Tectonic activity triggered by the gravitational influence of the gas giants causes landslides of icy debris.

Moonquakes may be smoothing out the surfaces of moons orbiting gas giant planets Jupiter and Saturn, new research has revealed. The findings could solve a long-standing mystery regarding why many of these icy moons have such smooth terrain.

Scientists have known for some time that some of the moons that orbit the gas giants Jupiter and Saturn, the largest and second-largest planet in the solar system respectively, are geologically active. This is the result of the massive gravitational influence of these planets that stretches and squeezes the moons orbiting them, triggering moonquakes that crack the moon’s crusts and icy surfaces.

This new research implies these moonquakes can also trigger landslides that help create smooth terrains. The link between moonquakes and landslides indicates how the surfaces of these moons evolve.

Steep ridges surrounded by relatively smooth areas are a common sight across the landscapes of the Jovian moons Europa and Ganymede, as well as Saturn’s moon Enceladus. While scientists have speculated that these features are the work of liquid flowing from icy volcanoes, quite how the process works at low temperatures on these frigid moons that are inhospitable to liquids, has been a puzzle.

The explanation put forward in this new research doesn’t require the presence of liquid on the surface of these icy moons, however.

The team came to the surprising conclusion when they set about measuring the dimensions of these ridges, thought to be steep slopes caused by the surface breaking along a fault line with one side dropping in what scientists call "tectonic fault scarps." They then applied the measurements to seismic models which allowed them to estimate the power of moonquakes in the history of these moons.

This revealed that some of these seismic events would have been strong enough to hoist up debris that then rolls downhill, spreading out as it does so and smoothing out the landscape of the moons.

"We found the surface shaking from moonquakes would be enough to cause surface material to rush downhill in landslides. We’ve estimated the size of moonquakes and how big the landslides could be," research lead author and University of Arizona in Tucson graduate student Mackenzie Mills, said in a statement. "This helps us understand how landslides might be shaping moon surfaces over time."

The research conducted by Mills during a series of summer internships at NASA’s Jet Propulsion Laboratory in Southern California will get a major boost when NASA’s Europa Clipper mission heads to Europa in 2024.

The Europa Clipper mission will orbit Jupiter and conduct about 50 flybys of Europa in the process, collecting images and scientific data with its payload of nine science instruments. This should also help planetary scientists determine if there is a deep liquid ocean beneath the icy shell of the Jovian moon and if it possesses the conditions needed to support life.

"It was surprising to find out more about how powerful moonquakes could be and that it could be simple for them to move debris downslope," Europa Clipper project scientist and research co-author Robert Pappalardo, said in the statement.

The team said it was particularly surprising to discover the strength of tectonic activity and quakes on Enceladus, as this moon of Saturn has less than 3% of the surface area of Europa and about 1/650 that of Earth.

"Because of that moon’s small gravity, quakes on tiny Enceladus could be large enough to fling icy debris right off the surface and into space like a wet dog shaking itself off," Pappalardo said. "We hope to gain a better understanding of the geological processes that have shaped icy moons over time and to what extent their surfaces may still be active today."

The team’s research is published in the journal Icarus.

Source: https://www.space.com/moonquakes-shape-surfaces-gas-giant-moons

Scientists recently discovered an asteroid that tags along with Earth during its yearly journey around the sun.

Dubbed 2023 FW13, the space rock is considered a "quasi-moon" or "quasi-satellite," meaning it orbits the sun in a similar time frame as Earth does, but is only slightly influenced by our planet’s gravitational pull. It is estimated to be 50 feet (15 meters) in diameter — roughly equivalent to three large SUVs parked bumper to bumper. During its orbit of the sun, 2023 FW13 also circles Earth, coming within 9 million miles (14 million kilometers) of our planet. For comparison, the moon has a diameter of 2,159 miles (3,474 km) and comes within 226,000 miles (364,000 km) of Earth at the closest point of its orbit, according to NASA.

2023 FW13 was first observed in March by the Pan-STARRS observatory, which is located atop the volcanic mountain Haleakalā in Hawaii. The asteroid’s existence was then confirmed by the Canada-France-Hawaii Telescope in Hawaii and two observatories in Arizona before being officially listed on April 1 by the Minor Planet Center at the International Astronomical Union, a network of scientists responsible for designating new planets, moons and other objects in the solar system.

Some estimates suggest that 2023 FW13 has been Earth’s cosmic neighbor since at least 100 B.C. and that the space rock will continue to follow this orbital path until around A.D. 3700, Adrien Coffinet, an astronomer and journalist who first categorized the asteroid as a quasi-moon after modeling its orbit, told Sky & Telescope.

"It seems to be the longest quasi-satellite of Earth known to date," Coffinet said.

Following 2023 FW13’s initial discovery in March, space observers dug into the data and found observations of the asteroid dating all the way back to 2012, according to Live Science’s sister site Space.com.

Despite hovering relatively close to Earth, this quasi-satellite likely isn’t on a collision course with our planet.

"The good news is, such an orbit doesn’t result in an impacting trajectory ‘out of the blue,’" Alan Harris, an astronomer at the Space Science Institute, told Sky & Telescope.

This is not Earth’s only quasi-companion; a different quasi-satellite known as Kamo’oalewa was discovered in 2016. The rock sticks similarly close to our planet during its orbit around the sun, and a 2021 study suggested that this asteroid could actually be a fragment of Earth’s moon.

Source: https://www.livescience.com/space/the-moon/new-quasi-moon-discovered-near-earth-has-been-travelling-alongside-our-planet-since-100-bc

[I didn't even know that humans existed in Europe 300,000 years ago! That is very old. That's even older than the period of time when humans supposedly left Africa! It raises many questions. Jan]

Footprints belonging to Homo heidelbergensis adults and children suggest that these human relatives foraged and played on the shores of a lake where prehistoric beasts gathered to drink.

In a forest clearing of birch and pine trees in what is today central Europe, herds of long-extinct beasts once gathered to drink on the shores of an ancient lake. Now, researchers have confirmed that early human relatives and their children foraged and bathed among them.

Three rare, 300,000-year-old footprints from a Lower Paleolithic (around 3 million to 300,000 years ago) fossil site in northwestern Germany reveal that Homo heidelbergensis, an extinct species of human that existed from about 700,000 to 200,000 years ago, co-existed with prehistoric elephants and rhinos, whose footprints were also found at the site. While a 2018 study in the journal Scientific Reports documented a similar neighborly relationship between early humans and prehistoric beasts in Ethiopia from 700,000 years ago, this is the first footprint evidence of H. heidelbergensis from Germany and only the fourth record of the species’ footprints worldwide.

"These three footprints represent a significant ‘direct’ proof of the hominin presence on the site," Flavio Altamura, an archeologist at the University of Tübingen in Germany and lead author of a study describing the fossils, told Live Science in an email. While one footprint clearly belonged to an adult, the others were much smaller. "Since two footprints are related to young individuals, this is also proof of the existence of children on the spot," Altamura said.

The discovery is remarkable because signs of children at prehistoric sites are scarce. Most of the evidence researchers have about the earliest periods of humanity comes from tools, human remains and food waste in the form of animal bones, Altamura explained. "You have to look for children’s bones, that are very rare, and it is very hard to link tools and food waste with children’s activity. So it is very difficult to say something about their behavior and the kind of life they were [leading]."

A picture of the 300,000-year-old hominin footprints discovered at a Paleolithic site in nortwesten Germany.

The newly found footprints provide clues about what it was like to be a child 300,000 years ago. "This is a rare snapshot of childhood in prehistory," Altamura said.

The footprints reveal aspects of our human relatives’ daily lives, which researchers describe in a study published May 12 in the journal Quaternary Science Reviews. The findings show that long-extinct "Heidelberg people" dwelled on the shores of an ancient lake among herds of the largest land animals at the time — prehistoric elephants called Palaeoloxodon antiquus that had straight tusks and weighed up to 13 tons (12 metric tons).

The researchers also unearthed tracks belonging to a rhinoceros, which they identified as Stephanorhinus kirchbergensis or S. hemitoechus. They are the first footprints of either species ever found in Europe.

The human footprints were probably left during a small family outing, Altamura said. "We may suggest that a small hominin group that included children was walking among elephants and other species on the muddy shore of an ancient lake, perhaps looking for and collecting food, or bathing, or just playing there."

These are not the oldest H. heidelbergensis children’s footprints unearthed among animal prints, however. A similar collection of human footprints and animal tracks was unearthed between 2013 and 2015 at a 700,000-year-old archeological site in Ethiopia called Melka Kunture. There, a cluster of tracks belonging to 11 adults and children potentially as young as 12 months old suggested that children were present when tools were made and animals butchered.

"Children and adult footprints were found on the border of a pond where other animals congregated and where hippos were butchered by hominins, suggesting that children were assisting adults and learning since their first years how to survive in the then wild environment," Altamura, who co-authored the 2018 study of the Ethiopian fossils, said.

Source: https://www.livescience.com/archaeology/300000-year-old-footprints-reveal-extinct-humans-went-on-a-lakeside-family-outing-among-giant-elephants-and-rhinos