Megalodon sharks, killed by supernova before Ice Age?


This August 2018 video says about itself:

The Truth Behind Why Megalodon Went Extinct

The megalodon was an amazing, powerful animal, and is an incredible part of our planet’s history—but that’s all it is now, history. New finds mean that we’re still making discoveries about how it lived, its life cycle and evolution. It died out because environmental changes and competition meant it couldn’t catch enough food to sustain itself, and with the state of our oceans today there’s little evidence to believe it’d fare any better now. Rather than fantasizing and investing time into the megalodon as a myth, we should listen to the plight of other creatures that now swim in its place, and help protect them before it’s too late.

From the University of Kansas in the USA:

Did supernovae kill off large ocean animals at dawn of Pleistocene?

December 11, 2018

Summary: The effects of a supernova — and possibly more than one — on large ocean life like school-bus-sized Megalodon 2.6 million years ago are detailed in a new article.

About 2.6 million years ago, an oddly bright light arrived in the prehistoric sky and lingered there for weeks or months. It was a supernova some 150 light years away from Earth. Within a few hundred years, long after the strange light in the sky had dwindled, a tsunami of cosmic energy from that same shattering star explosion could have reached our planet and pummeled the atmosphere, touching off climate change and triggering mass extinctions of large ocean animals, including a shark species that was the size of a school bus.

The effects of such a supernova — and possibly more than one — on large ocean life are detailed in a paper just published in Astrobiology.

“I’ve been doing research like this for about 15 years, and always in the past it’s been based on what we know generally about the universe — that these supernovae should have affected Earth at some time or another”, said lead author Adrian Melott, professor emeritus of physics & astronomy at the University of Kansas. “This time, it’s different. We have evidence of nearby events at a specific time. We know about how far away they were, so we can actually compute how that would have affected the Earth and compare it to what we know about what happened at that time — it’s much more specific.”

Melott said recent papers revealing ancient seabed deposits of iron-60 isotopes provided the “slam-dunk” evidence of the timing and distance of supernovae.

“As far back as the mid-1990s, people said, ‘Hey, look for iron-60. It’s a telltale because there’s no other way for it to get to Earth but from a supernova.’ Because iron-60 is radioactive, if it was formed with the Earth it would be long gone by now. So, it had to have been rained down on us. There’s some debate about whether there was only one supernova really nearby or a whole chain of them. I kind of favor a combo of the two — a big chain with one that was unusually powerful and close. If you look at iron-60 residue, there’s a huge spike 2.6 million years ago, but there’s excess scattered clear back 10 million years.”

Melott’s co-authors were Franciole Marinho of Universidade Federal de Sao Carlos in Brazil and Laura Paulucci of Universidade Federal do ABC, also in Brazil.

According to the team, other evidence for a series of supernovae is found in the very architecture of the local universe.

“We have the Local Bubble in the interstellar medium,” Melott said. “We’re right on its edge. It’s a giant region about 300 light years long. It’s basically very hot, very low-density gas — nearly all the gas clouds have been swept out of it. The best way to manufacture a bubble like that is a whole bunch of supernovae blows it bigger and bigger, and that seems to fit well with idea of a chain. When we do calculations, they’re based on the idea that one supernova that goes off, and its energy sweeps by Earth, and it’s over. But with the Local Bubble, the cosmic rays kind of bounce off the sides, and the cosmic-ray bath would last 10,000 to 100,000 years. This way, you could imagine a whole series of these things feeding more and more cosmic rays into the Local Bubble and giving us cosmic rays for millions of years.”

Whether or not there was one supernova or a series of them, the supernova energy that spread layers of iron-60 all over the world also caused penetrating particles called muons to shower Earth, causing cancers and mutations — especially to larger animals.

“The best description of a muon would be a very heavy electron — but a muon is a couple hundred times more massive than an electron,” Melott said. “They’re very penetrating. Even normally, there are lots of them passing through us. Nearly all of them pass through harmlessly, yet about one-fifth of our radiation dose comes by muons. But when this wave of cosmic rays hits, multiply those muons by a few hundred. Only a small faction of them will interact in any way, but when the number is so large and their energy so high, you get increased mutations and cancer — these would be the main biological effects. We estimated the cancer rate would go up about 50 percent for something the size of a human — and the bigger you are, the worse it is. For an elephant or a whale, the radiation dose goes way up.”

A supernova 2.6 million years ago may be related to a marine megafaunal extinction at the Pliocene-Pleistocene boundary where 36 percent of the genera were estimated to become extinct. The extinction was concentrated in coastal waters, where larger organisms would catch a greater radiation dose from the muons.

According to the authors of the new paper, damage from muons would extend down hundreds of yards into ocean waters, becoming less severe at greater depths: “High energy muons can reach deeper in the oceans being the more relevant agent of biological damage as depth increases,” they write.

Indeed, a famously large and fierce marine animal inhabiting shallower waters may have been doomed by the supernova radiation.

“One of the extinctions that happened 2.6 million years ago was Megalodon,” Melott said. “Imagine the Great White Shark in ‘Jaws‘, which was enormous — and that’s Megalodon, but it was about the size of a school bus. They just disappeared about that time. So, we can speculate it might have something to do with the muons. Basically, the bigger the creature is the bigger the increase in radiation would have been.”

The KU researcher said the evidence of a supernova, or series of them, is “another puzzle piece” to clarify the possible reasons for the Pliocene-Pleistocene boundary extinction.

“There really hasn’t been any good explanation for the marine megafaunal extinction,” Melott said. “This could be one. It’s this paradigm change — we know something happened and when it happened, so for the first time we can really dig in and look for things in a definite way. We now can get really definite about what the effects of radiation would be in a way that wasn’t possible before.”

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Puerto Rican Hurricane Maria disaster, new studies


This 30 November 2017 video says about itself:

Through Our Eyes: Life in Puerto Rico After Hurricane Maria | NowThis

Here’s a glimpse at what life is like in post-hurricane Puerto Rico, where American citizens are still without clean water, food, or electricity.

From NASA/Goddard Space Flight Center in the USA:

New look at Puerto Rico post-Hurricane Maria

December 10, 2018

When Hurricane Maria struck Puerto Rico head-on as a Category 4 storm with winds up to 155 miles per hour in September 2017, it damaged homes, flooded towns, devastated the island’s forests and caused the longest electricity black-out in U.S. history.

Two new NASA research efforts delve into Hurricane Maria‘s far-reaching effects on the island’s forests as seen in aerial surveys and on its residents’ energy and electricity access as seen in data from space. The findings, presented Monday at the American Geophysical Union meeting in Washington, illustrate the staggering scope of Hurricane Maria’s damage to both the natural environment and communities.

An Island Gone Dark

At night, Earth is lit up in bright strings of roads dotted with pearl-like cities and towns as human-made artificial light takes center stage. During Hurricane Maria, Puerto Rico’s lights went out.

In the days, weeks and months that followed, research physical scientist Miguel Román at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and his colleagues developed neighborhood-scale maps of lighting in communities across Puerto Rico. To do this, they combined daily satellite data of Earth at night from the NASA/NOAA Suomi National Polar-orbiting Partnership satellite with USGS/NASA Landsat data and OpenStreetMap data. They monitored where and when the electricity grid was restored, and analyzed the demographics and physical attributes of neighborhoods longest affected by the power outages.

A disproportionate share of long-duration power failures occurred in rural communities. The study found that 41 percent of Puerto Rico’s rural municipalities experienced prolonged periods of outage, compared to 29 percent of urban areas. When combined, power failures across Puerto Rico’s rural communities accounted for 61 percent of the estimated cost of 3.9 billion customer-interruption hours, six months after Hurricane Maria. These regions are primarily rural in the mountainous interior of the island where residents were without power for over 120 days. However, even more heavily populated areas had variable recovery rates between neighborhoods, with suburbs often lagging behind urban centers.

The difference between urban and rural recovery rates is in part because of the centralized set-up of Puerto Rico’s energy grid that directs all power to prioritized locations rather than based on proximity to the nearest power plant, Román said. Areas were prioritized, in part, based on their population densities, which is a disadvantage to rural areas. Within cities, detached houses and low-density suburban areas were also without power longer.

“It’s not just the electricity being lost,” Román said. “Storm damage to roads, high-voltage power lines and bridges resulted in cascading failures across multiple sectors, making many areas inaccessible to recovery efforts. So people lost access to other basic services like running water, sanitation, and food for extended time periods.”

The absence of electricity as seen in the night lights data offers a new way to visualize storm impacts to vulnerable communities across the entirety of Puerto Rico on a daily basis. It’s an indicator visible from space that critical infrastructure, beyond power, may be damaged as well, including access to fuel and other necessary supplies. The local communities with long-duration power outages also correspond to areas that reported lack of access to medical resources.

The next step for Román when looking at future disasters is to go beyond night lights data and sync it up with updated information on local infrastructure — roads, bridges, internet connectivity, clean water sources — so that when the lights are out, disaster responders can cross-reference energy data with other infrastructure bottlenecks that needs to be solved first, which would help identify at-risk communities and allocate resources.

The Buzz-Cut Forest

Hurricane Maria’s lashing rain and winds also transformed Puerto Rico’s lush tropical rainforest landscape. Research scientist Doug Morton of Goddard was part of the team of NASA researchers who had surveyed Puerto Rico’s forests six months before the storm. The team used Goddard’s Lidar, Hyperspectral, and Thermal (G-LiHT) Airborne Imager, a system designed to study the structure and species composition of forests. Shooting 600,000 laser pulses per second, G-LiHT produces a 3D view of the forest structure in high resolution, showing individual trees in high detail from the ground to treetop. In April 2018, post-Maria, the team went back and surveyed the same tracks as in 2017.

Comparing the before and after data, the team found that 40 to 60 percent of the tall trees that formed the canopy of the forest were damaged, either snapped in half, uprooted by strong winds or lost large branches.

“Maria gave the island’s forests a haircut,” said Morton. “The island lost so many large trees that the overall height of forests was shortened by one-third. We basically saw 60 years’ worth of what we would otherwise consider natural treefall disturbances happen in one day.”

The extensive damage to Puerto Rico’s forests had far-reaching effects, Morton said. Fallen trees that no longer stabilize soil on slopes with their roots as well as downed branches can contribute to landslides and debris flows, increased erosion, and poor water quality in streams and rivers where sediments build up.

In addition, the lidar surveys across the island corroborate findings presented at AGU by ecologist Maria Uriarte at Columbia University in New York City, who looked at tree death and damage rates in ground plots at the National Science Foundation Luquillo Long-Term Ecological Research site. Uriarte found certain tree species were more susceptible to the high wind damage, while others such as the palms, survived at higher rates, along with shrubs and shorter trees in the understory.

Morton and Uriarte will continue to follow the fate of Puerto Rican forests as they recover from hurricane damages using laser technology from the ground to make detailed measurements of forest regrowth.

Researchers at the University of New Hampshire have found unprecedentedly high levels of nitrate, an essential plant nutrient, in streams and watersheds of Puerto Rico for a year after two consecutive major hurricanes in 2017. This high amount of nitrate may have important climate change implications that could harm forest recovery and threaten ecosystems along Puerto Rico’s coastline by escalating algal blooms and dead zones: here.

Spacecraft records Martian wind sound


This 7 December 2018 video says about itself:

Sounds of Mars: NASA’s InSight Senses Martian Wind

Listen to Martian wind blow across NASA’s InSight lander. The spacecraft’s seismometer and air pressure sensor picked up vibrations from 10-15 mph (16-24 kph) winds as they blew across Mars’ Elysium Planitia on Dec. 1, 2018.

The seismometer readings are in the range of human hearing, but are nearly all bass and difficult to hear on laptop speakers and mobile devices. We provide the original audio and a version pitched up by two octaves to make them audible on mobile devices. Playback is suggested on a sound system with a subwoofer or through headphones. Readings from the air pressure sensor have been sped up by a factor of 100 times to make them audible.

For full-length uncompressed .wav files, visit NASA.gov/sounds. For more about the InSight mission, visit mars.nasa.gov/insight.

4,000-year-old termite mounds in Brazil


This 19 November 2018 video says about itself:

A vast array of 200 million termite mounds have existed in NE Brazil for up to 4,000 years. These mounds cover 230,000 km2, an area similar to that of the UK, and are the result of the excavation of 10 km3 of soil during the construction of a massive underground network of tunnels. A combination of time and interconnectivity of the tunnels has allowed a regular (over-dispersed) pattern of mounds to emerge through self-organizational processes driven by episodic leaf fall.

From ScienceDaily:

4,000-year-old termite mounds found in Brazil are visible from space

November 20, 2018

Researchers reporting in Current Biology on November 19 have found that a vast array of regularly spaced, still-inhabited termite mounds in northeastern Brazil — covering an area the size of Great Britain — are up to about 4,000 years old.

The mounds, which are easily visible on Google Earth, are not nests. Rather, they are the result of the insects’ slow and steady excavation of a network of interconnected underground tunnels. The termites’ activities over thousands of years has resulted in huge quantities of soil deposited in approximately 200 million cone-shaped mounds, each about 2.5 meters tall and 9 meters across.

“These mounds were formed by a single termite species that excavated a massive network of tunnels to allow them to access dead leaves to eat safely and directly from the forest floor”, says Stephen Martin of the University of Salford in the UK. “The amount of soil excavated is over 10 cubic kilometers, equivalent to 4,000 great pyramids of Giza, and represents one of the biggest structures built by a single insect species.”

“This is apparently the world’s most extensive bioengineering effort by a single insect species”, adds Roy Funch of Universidade Estadual de Feira de Santana in Brazil. “Perhaps most exciting of all — the mounds are extremely old — up to 4,000 years, similar to the ages of the pyramids.”

The mounds are largely hidden from view in the fully deciduous, semiarid, thorny-scrub caatinga forests unique to northeastern Brazil. They’d only really come into view by “outsiders”, including scientists, when some of the lands were cleared for pasture in recent decades.

Soil samples collected from the centers of 11 mounds and dated indicated that the mounds were filled 690 to 3,820 years ago. That makes them about as old as the world’s oldest known termite mounds in Africa.

The researchers investigated whether the strangely regular spatial pattern of the mounds was driven by competition amongst termites in neighboring mounds. Their behavioral tests found little aggression at the mound level. That’s compared to obvious aggression amongst termites collected at greater distances from one another.

The findings lead the researchers to suggest that the over-dispersed spatial mound pattern isn’t generated by aggressive interactions. Instead, Martin and his colleagues propose that the mound pattern arose through self-organizational processes facilitated by the increased connectivity of the tunnel network and driven by episodic leaf-fall in the dry forest.

They say that a pheromone map might allow the termites to minimize their travel time from any location in the colony to the nearest waste mound. The vast tunnel network apparently allows safe access to a sporadic food supply, similar to what’s been seen in naked mole-rats, which also live in arid regions and construct very extensive burrow networks to obtain food, the researchers report.

“It’s incredible that, in this day and age, you can find an ‘unknown’ biological wonder of this sheer size and age still existing, with the occupants still present”, Martin says.

The researchers say there are many questions still to pursue. For instance, no one knows how these termite colonies are physically structured because a queen chamber of the species has never been found.

British demonstration against Trump’s wars, spying, militarization of space


This 20 May 2017 video from the USA says about itself:

Trump in Saudi Arabia: More U.S. Weapons for Devastating Yemen War

Medea Benjamin, co-founder of Code Pink and author of “Kingdom of the Unjust: Behind the U.S.-Saudi Connection“, says President Donald Trump’s visit to Saudi Arabia deepens a “toxic” tie between Washington and the House of Saud.

From daily The Morning Star in Britain:

Thursday, October 4, 2018

Peace campaigners to march on US air force comms base

PEACE campaigners will march on a major US air force communications centre at RAF Croughton on Saturday.

The Pentagon is embarked on a £200 million upgrade to the base on the Oxfordshire-Northamptonshire border to turn it into a “major international intelligence hub” housing the new Joint Intelligence Analysis Centre and 1,500 US military and intelligence staff.

It is also planned to be a ground station for the “space force” planned by US President Donald Trump to establish “American dominance in space.”

Oxford CND’s Nigel Day said the base would help co-ordinate lethal drone strikes in Yemen, Somalia and the Sahel region of north Africa, after Germany told the US that it could not use its Ramstein base in the country’s south-west for “death-dealing” activities.

“We don’t want this development. It drags us into Nato and US aggression abroad,” Mr Day told the Morning Star.

A minibus organised by the Oxfordshire Peace Campaign leaves St Giles, Oxford, at 10.45am and Oxford railway station at 11am. Tickets are priced £8 and pre-booking is essential on (01865) 248-357 or oxonpeace@yahoo.co.uk.

The rally at Croughton will run from noon to 4pm.

Photos from asteroid Ryugu


This video says about itself:

Why Japan Is Landing Hopping Robots On An Asteroid

25 September 2018

The Japanese space agency, JAXA, has become the first country to land two rovers on an asteroid. But these rovers, called Rover1A and Rover1B, aren’t your ordinary rovers that explore a new world by driving on it. These rovers hop. And they will hop all over asteroid Ryugu for science.

By Lisa Grossman, 6:30pm, September 24, 2018:

The first rovers to explore an asteroid just sent photos home

The ‘Wish-you-were-here’ pictures show Ryugu’s surface

The first rovers to explore the surface of an asteroid have landed. After touching down September 21, the vehicles took pictures of asteroid Ryugu and at least one hopped around.

Japan’s Hayabusa2 spacecraft, which arrived at the near-Earth asteroid on June 27 after a journey of more than three years, released the MINERVA-II1 container from a height of about 60 meters (SN Online: 6/27/18). The container then released two 18-centimeter-wide, cylindrical rovers. Because Ryugu’s gravity is so weak, the rovers can hop using rotating motors that generate a torque and send them airborne for about 15 minutes.

Japan’s Aerospace Exploration Agency released the first blurry, otherworldly pictures from the rovers on September 22. One image appears to have been taken midhop.

Japan sent its first MINERVA rover with the original Hayabusa mission, which reached asteroid Itokawa in 2005, but that rover missed the asteroid and was lost in space. “I was so moved to see these small rovers successfully explore an asteroid surface because we could not achieve this at the time of Hayabusa 13 years ago”, wrote Hayabusa2’s project mission manager, Makoto Yoshikawa, on the mission’s webpage.

A German and French rover, also aboard Hayabusa2, is set to deploy to Ryugu on October 4. MASCOT will join the MINERVA-II1 rovers in measuring the asteroid’s composition, temperature and magnetic properties. A third MINERVA-II rover is scheduled to land sometime in 2019.

Later in October, the Hayabusa2 spacecraft is scheduled to touch down at a spot near the asteroid’s equator to gather a sample of dust, before returning to orbit. Depending on how that sample collection goes, the craft may try to collect two more samples from different parts of the asteroid. If successful, the spacecraft will send the asteroid dust back to Earth, to arrive in 2020.

See also here.

Trans-Pluto dwarf planet Ultima Thule, first spaceship photos


This 30 August video says about itself:

NASA’s Pluto probe spots the next deep space rock it’s zooming toward

NASA’s New Horizons spacecraft, known for flying by Pluto in 2015, has finally spotted its next target at the edge of the Solar System. On August 16th, the distant probe captured its first images of the space rock it’s currently zooming toward — an icy body nearly 20 miles across that’s been nicknamed Ultima Thule.

It’s a major milestone for the New Horizons team as they prepare the spacecraft for its rendezvous with Ultima Thule on New Year’s Day 2019.

The New Horizons spacecraft has been en route to Ultima Thule ever since October 2015, just a few months after it flew by Pluto in July.

Following the Pluto meet-up, NASA decided to extend the New Horizons mission so that the vehicle would fly by another target in the distant Solar System. The mission team selected Ultima Thule, also named 2014 MU69, since it’s in an ideal position beyond Pluto, and it didn’t take too much fuel for New Horizons to change course to meet up with the rock.

By Christopher Crockett, 2:39pm, August 29, 2018:

New Horizons has sent back the first images of Ultima Thule, its next target

New Horizons has its next destination in sight.

The spacecraft, which buzzed Pluto in 2015, captured its first images on August 16 of the remote icy world nicknamed Ultima Thule, confirming that New Horizons is on track for its January 1 flyby. With about 160 million kilometers to go — roughly the same distance as Earth is from the sun — the tiny world appears as no more than a faint speck in the probe’s camera.

The pictures also barely set a new record: At roughly 6 billion kilometers from Earth, they are the farthest images ever taken. For decades, that honor was held by the Voyager 1 spacecraft, which in 1990 snapped pictures of Earth and many of our neighboring planets from nearly the same distance.

Officially dubbed 2014 MU69, Ultima Thule is part of the Kuiper Belt, a field of frozen detritus left over from the formation of the planets 4.6 billion years ago. By sending New Horizons to take pictures and measure the chemical makeup of Ultima’s surface, researchers hope to unearth clues about the origin of our solar system.