The day the dinosaurs' world fell apart - BBC News - Canadanewsmedia
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The day the dinosaurs' world fell apart – BBC News

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Scientists have a recording of the worst day on Earth; certainly the worst day in the last 66 million years.

It takes the form of a 130m section of rock drilled from under the Gulf of Mexico.

These are sediments that were laid down in the seconds to hours after a huge asteroid had slammed into the planet.

You’ll know the event we’re talking about – the one researchers now think was responsible for the demise of the dinosaurs and the rise of mammals.

The high-resolution account of this catastrophe was recovered by a UK/US-led team, who spent several weeks in 2016 drilling into what remains of the crater produced by the impact.

Today, this 200km-wide structure is positioned under Mexico’s Yucatan Peninsula, with its best preserved central portions sitting just offshore of the port of Chicxulub.

The team pulled up a great long core of rock but it’s a particular 130m-long section that essentially documents the first day of what geologists call the Cenozoic Era, or as some others like to refer to it: the Age of Mammals.


Chicxulub Crater – The impact that changed life on Earth

  • A 12km-wide object dug a hole in Earth’s crust 100km across and 30km deep
  • This bowl then collapsed, leaving a crater 200km across and a few km deep
  • The crater’s centre rebounded and collapsed again, producing an inner ring
  • Today, much of the crater is buried offshore, under 600m of sediments
  • On land, it is covered by limestone, but its rim is traced by an arc of sinkholes

The section is a nightmarish jumble of shattered material, but its contents are arranged in such a way that scientists say they can discern a clear narrative.

The bottom 20m or so, is dominated by glassy debris. This is the rock that was melted by the heat and pressure of the impact. It lapped across the base of the crater in the subsequent seconds and minutes.

This then transitions to a lot of fragmented melt rock – the result of explosions as water rushed across the hot material.

The water came from the shallow sea covering the area at the time. It would have been pushed temporarily out of the way by the impact but when it came back in and made contact with the broiling rock, it would have set off violent reactions. Something similar occurs at volcanoes where magma interacts with seawater.

This phase covers the first minutes to an hour. But the water keeps coming, filling up the crater, and the top 80-90m of the core section is built from all the debris that was in this water and ultimately rained out. Larger fragments initially followed by finer and finer material.

The timescale for this is the first hours after the impact.

And then, right at the top of the 130m core section is evidence of a tsunami. The sediments all dip in one direction and their organisation suggests they were deposited in a high-energy event.

Scientists say the impact would have generated a giant wave pulse that would have crashed on to shorelines hundreds of kilometres from the crater. But this outward train would also have had a return pulse and it’s the debris carried in this tsunami that caps the top of the rock sequence.

“This is all still Day One,” says Prof Sean Gulick from the University of Texas at Austin. “Tsunamis move at the speed of a jet plane. Twenty-four hours is a generous amount of time for the waves to move out and come back in again,” he told BBC News.

Prof Gulick’s team is confident in the tsunami interpretation because mixed in with the deposits are soil markers, and charcoal – evidence of the great fires that would have been triggered on nearby landmasses by the heat of the impact – all brought back to the crater by the returning wave pulse.

Strikingly, what the team doesn’t see anywhere in the 130m core is any evidence of sulphur-containing rocks. That’s surprising because the asteroid would have hit a seafloor made up of perhaps a third to half by sulphur-containing minerals, such as gypsum.

For some reason, the sulphur must have been preferentially ejected or vaporised. But this only goes to support the popular theory now for how the dinosaurs met their demise.

So much sulphur mixed with water and injected into the sky would have dramatically cooled the climate, making life a struggle for all sorts of plant and animal life.

“There was a global climate model run with just a hundred gigatonnes (billion tonnes) of sulphur injected into the atmosphere and that came up with 25C cooling for at least 15 years, which puts most of the planet below freezing,” said Prof Gulick.

“And the conservative estimate for the amount of sulphur released in 325 gigatonnes. That’s orders of magnitude more than you would get from any volcano like a Krakatau which can also cool the climate for a short period.”

The research is published in the Proceedings of the National Academy of Sciences (PNAS).

Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos

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Billionaire Bezos unveils plans to land humans on Moon, with a little help from some old friends – The Register

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Blue Origin and industry vets eye a slice of NASA’s lunar lander largesse

Richest person in the world, Jeff Bezos, yesterday pitched NASA a team mostly made up of the usual suspects to build a lunar lander for the agency’s ambitious 2024 boots-on-Moon goal.

Speaking at the International Astronautical Congress in Washington, Bezos announced the “national team”, of which his Blue Origin would be the prime contractor (naturally). The members consist of Lockheed Martin for the Ascent Stage, Northrop Grumman for the Transfer Element and Draper providing the guidance and navigation systems.

“We could not ask for better partners,” intoned the billionaire, which is fair enough. After all, elements of all the companies in the team-up worked on the Apollo program back in the day (although those engineers will have long been put out to pasture.)

The Transfer Element will guide the stack from lunar orbit to close to the Moon, from whence the Descent Element will conduct a powered descent. Lockheed Martin’s ascent module will then send the freshly minted Moonwalkers back into space.

Blue Origin will also be building the descent element of the lander, which uses the company’s BE-7 engine. The powerplant, Bezos said, is fuelled by liquid hydrogen and oxygen and as well being “highly throttleable” and developing 10,000 pounds of thrust.

The BE-7, of course, has yet to actually leave the test stand. Bezos told the audience that to date, the company had managed 13 minutes of test time, including a three-minute continuous firing.

That same engine, Bezos added, would be used by Northrop Grumman in the transfer element of the lunar lander stack.

Bezos unveiled the Blue Moon lander back in May and the announcement of the National Team is an indicator that it will take more than one company to meet the 2024 goal. It will also reassure those within NASA nervous about flinging cash at a company that has yet to even make Earth orbit, let alone do anything in deep space.

And NASA has lots of experience in giving money to Lockheed Martin and Northrop Grumman after all.

Grumman, of course, built the original Apollo Lunar Module back in NASA’s glory days while Draper provided the guidance systems for the Moon missions.

These days, Northrop Grumman provides NASA with ISS cargo services and is working on both the boosters for the eternally-delayed Space Launch System and the habitat for the agency’s Lunar Gateway.

Draper has continued to work on precision guidance, although there is a delightful hole to tumble down in researching the Apollo guidance units, particularly efforts to fire up the old things once more. Naturally, the hand-woven circuitry of the Apollo era won’t feature this time around.

NASA is due to select two contractor teams in late 2020 to actually build the lander, having asked for proposals (and deleted certain reusability requirements in the rush to 2024). ®

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Bezos's Blue Origin partners with Lockheed, others on moon lander – Financial Post

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WASHINGTON — U.S. billionaire Jeff Bezos said on Tuesday his space company Blue Origin has signed agreements with Lockheed Martin Corp, Northrop Grumman Corp and research and development organization Draper for development of its lunar lander designed to help NASA put humans on the moon by 2024.

Blue Origin’s so-called Blue Moon lunar lander, unveiled by Bezos in May, is in development and sits at the center of the space company’s ambition to ferry humans into deep space and land key contracts from the U.S. space agency for space exploration.

“I’m excited to announce that we put together a national team to go back to the moon,” Bezos, founder and CEO of online retail giant Amazon, said at the International Astronautical Congress.

The four companies, with Blue Origin as the lead contractor, plan to submit a proposal for the lander to NASA under its Artemis lunar program, an accelerated mission to the moon kickstarted in March by U.S. Vice President Mike Pence.

Bezos called the partnerships a “national team” whose history in space exploration fits the Blue Moon’s mission. Lockheed is separately developing the moon-bound astronaut capsule named Orion. Northrop helped NASA build the Apollo lunar landers in the 1960s. Draper, a not-for-profit research and development organization, built NASA’s navigation computers for Apollo lunar landers. (Reporting by Joey Roulette; Editing by Sandra Maler)

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A giant full beaver moon set to dazzle Metro Vancouver skies – Vancouver Courier

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While it is getting darker earlier in Metro Vancouver, this month’s full beaver moon promises to illuminate the night sky.

The November full moon is thought to have derived its funny name because it occurred during the optimal time to trap the furry creatures. In fact, both colonial Americans as well as the Algonquin tribes referred to it as such.

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“Why this name? Back then, this was the month to set beaver traps before the swamps froze, to ensure a supply of warm winter furs,” reports Farmer’s Almanac.

While it is commonly known as the beaver moon, it was also called the Full Frost Moon by other North American Tribes.

According to the Old Farmer’s Almanac, the moon will be fullest during the day on Tuesday, Nov. 12. However, Vancouver stargazers will still be able to see the nearly-full moon in all her celestial glory the night before (Nov. 11) as well as later that night (Nov. 12).

What’s more, this full moon casts long, hauntingly beautiful shadows in the Northern Hemisphere. They are similar to those cast by the midday summer sun, as the moon is extremely high in the sky during this time.

Stargazers should opt to travel as far away from city lights as possible in order to avoid light pollution that will obscure the clarity of heavenly bodies. While this works best the in more remote places, anywhere that has a higher elevation will also provide more ideal viewing conditions.

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