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Climate change: What fossils and paleontology say about Earth’s future –



When Thomas Halliday was a young lad in the village of Rannoch, Scotland, he loved exploring the Caledonian Forest. The pinewoods were like living fossils, a remnant of the last glacial period and a bygone age when the west coast of Scotland was covered in trees. “It was such a diverse and wonderful place to explore as a 7-year-old,” Halliday told Vox. “I essentially had free rein to go and run about, and I became very interested in the natural world.”

Fittingly, the boy who explored the ancient forest went on to become a paleontologist. In his new book, Otherlands: A Journey Through Earth’s Extinct Worlds, out this week, Halliday writes about primordial history as though we could witness it first-hand, bringing life to prehistoric geese that were as ornery as their modern-day cousins, towering forests that transformed our planet, and dinosaurs that lived before the evolution of flowers.

“By visiting extinct sites with the mindset of a traveler, a safari-goer, I hope to bridge the distance from the past to the present,” Halliday writes. He dives into the fossil record and invites readers to “see ancient life forms as if they were commonplace visitors to our world, as quivering, steaming beasts of flesh and instinct, as creaking beams and falling leaves.”

I recently spoke with Halliday about the clues the past leaves for us. He told me that “temporal wanderlust,” or a hunger to understand eras that were different from our own, can teach lessons about the future of the planet and the grave dangers of human-caused climate change. Our conversation has been edited for length and clarity.

You describe this book as a travelogue through time. What inspired that idea?

When people think of paleontology, they tend to think of skeletons in a museum. It’s very separated from the living creature. And when it is presented as a living creature, it’s usually in some sort of monster film, out for human blood. This isn’t really how creatures behave in reality. The past isn’t this barbaric age, you know? It was a real, functioning, biological system. So I thought, “If we can visit the Cairngorms [a mountain range in Scotland] and talk about their wonderful biology, then why not interpret the fossil record in such a way that it becomes sort of like visiting those worlds?”

The chapters of your book read like vivid descriptions of a day in time — say, a Tuesday in the Pleistocene. How did you do that? How did you collect the details of the weather or the behaviors of animals?

The behavioral side of things and the climatic side of things are obviously not directly observed, they are inferred. If you look at sedimentology, there are patterns of grains in the rock that tell you something about the environment. For example, in the Miocene chapter, about 4 million years ago at Gargano [present-day Italy], the Mediterranean Sea has dried out and we’re on this island. There’s a giant, flightless goose there. It has a bony spur on its wing, which is an anatomical feature that you can directly observe [in fossils]. And we know birds today have this kind of spur on their wing for fighting. We can then reconstruct that this is a behavior that probably happened among these geese on Gargano. It’s probably something that is happening within the flock, between birds of the same species, rather than defense against predators, because of what we can see in today’s biology.

Many of your chapters are set on the cusp of disaster, either right before or right after. Why are these events so useful when you’re looking for stories in the past?

Part of it is because they are incredibly important in telling the story of life. There have been several mass extinctions, and the way that life responded to them is very important — not just for telling us what’s happened in the past, but what’s going to happen in the future. Everything in my chapter on the Oligocene is represented as fossils in what’s called a lahar, which is what happens when a volcano has erupted and you have this layer of ash that turns into a sort of slurry, which goes down mountainsides at horrendous speeds and buries everything. There’s little chance for things to escape. In Tinguiririca [present-day Chile], we see the remnants of mammals in this lahar, so I’m talking very specifically about particular individuals.

At one point you describe one of the earliest species that might have been lost to our human ancestors, or hominins. How far back can you see those impacts?

Right, so this is about 4 million years ago in what is now Lake Turkana. This is sort of a cradle of African fauna. There are several species of relatives of elephants, and there are a couple of giraffe species, and there’s early wildebeests, antelopes, and the ancestors of the domestic cat. All sorts of creatures that are very familiar to us now.

There are these bear otters, which are lion-sized otters that used to live alongside early hominins. And they have no living relatives, so this is a group that has gone extinct. Some people have suggested — although this is a little controversial — that because they had a similar sort of generalist diet to humans, perhaps the bear otters were out-competed and essentially sort of lost their place in the ecosystem.

We’re not talking about Homo sapiens. We’re talking about three-foot-tall Australopithecines. They’re some of the first species that we can confidently say are on the human lineage.

When you begin to talk about humans directly impacting ecosystems, that comes much later. There’s good evidence for people managing fire and using fire to clear ecosystems and to change the forest layout tens of thousands of years ago. And even in what we would today think of as relatively undisturbed ecosystems, like the Amazon jungle, there’s been thousands of years of very active management by people. Even though it’s not been done in the sort of open plantations we’re used to in Europe and North America, it’s a landscape which has been highly modified by humans.

Throughout your book, you write about animals evolving to adapt to changes. Why can’t the natural world adapt to what’s happening to the planet now?

The simple answer is that it’s far too fast. Some degree of warming and cooling is absolutely a natural cycle, but the way we’re doing it now is entirely unnatural. When we talk about the changes that occur on geological timescales, they’re typically extremely slow. The fastest-known increase in carbon dioxide concentration is happening now.

When you get rapid changes in climate, however temporary, you often then get a big transition in what life is doing. At the end of the Permian, 250 million years ago, was what’s known as the Great Dying. It is the worst mass extinction that has ever happened. There was a huge outgassing of things like methane and other greenhouse gases from volcanic activity. In Siberia, 95 percent of life was wiped out by this radical change in global climate. There were huge problems with ocean acidification, with these gases going out into the atmosphere, and a loss of oxygen in the oceans. And a lot of these things are problems that we are seeing now.

“Otherlands: A Journey Through Earth’s Extinct Worlds” was published on February 1, 2022, by Random House.
Lucas Heinrich (cover design) and Chris Wormell (cover illustration) for Penguin Random House

Are there any other organisms that have changed the biosphere in the way that humans have?

Yeah, absolutely. One of the classic stories is the first photosynthesizers. Photosynthesis is the process that turns carbon dioxide and light into oxygen and sugar and energy. This was first done by single-celled organisms billions of years ago, and before then there wasn’t really much oxygen on Earth. When the photosynthesizers started producing oxygen, it completely changed the atmospheric composition. Most of the microorganisms that lived on Earth were not really able to tolerate oxygen, and so it caused problems for them.

More recently, 360 million years ago or so, we have the scale trees. This is in the period that’s called the Carboniferous, when we really get the first big plants. These scale tree forests formed in sort of swampy conditions, there’s a huge growth in plant material, they’re absorbing lots of carbon dioxide from the air. All of this carbon that was in the atmosphere was absorbed by growing plants, the plants that died fell into the swamp, and their bodies were converted into peat and then into coal and then buried, and so all of this carbon was captured. All of this served to change the global climate. It made the world cooler.

Very shortly after, you get what’s known as the Carboniferous rainforest collapse. The plants have changed the world’s climate such that swamps are no longer a common ecosystem, and scale trees and their kin go extinct. In a sense, they sowed the seeds of their own destruction.

How are humans different from the other organisms that have changed the planet?

Well, we as conscious beings are able to reflect on our actions. We are able to predict what the outcome of our actions will be, and therefore to choose an appropriate path. The first experiments that showed that carbon dioxide caused air to warm faster were done by a woman called Eunice Foote in the late 19th century, about two years before the first oil well was dug in the US. And for various reasons, despite having known about the warming effects of greenhouse gases for well over 100 years, little has been done so far.

I am always hopeful, though. There is now a movement to choose the right path and to recognize what we’ve already lost forever, and what we can salvage. Every day we go on without changing things, things are going to get worse, but there’s never going to be a single point at which all is lost. We can always, as a society, choose the right path.

In your last chapter, you write that human-induced change is not new, and can even sort of be considered natural. How is the intervention natural? And how should we think about it going forward?

It’s natural in the sense that we are part of the biological world and that we should not try and consider ourselves apart from it. We have been part of this world as a species for 200,000 years and as a genus for 2 million years. There are so many species that we have evolved alongside. We depend on that biological world that we are tightly integrated into. It’s a very unusual time in Earth’s history, in that all the ecosystems of the world, from the bottom of the sea to the tops of mountains, are affected by the actions of this single species.

Are there periods in the past that you think are particularly important parallels for us to pay attention to as we look to the climate-changed future?

If we’re talking about climate change, the important periods are the five major mass extinction events. The Ordovician is the only one which was caused by global cooling, and I think is an important parallel here. People have an assumption that warmth is somehow what is bad here. But in fact it’s not the warmth itself, it’s the rate of change.

At the end of the Ordovician, you get this onset of glaciers that expanded out across the whole of Africa and South America, which at that time were joined. And when that happens, we see a big extinction event in marine organisms as they are forced into deeper water, which perhaps they can’t survive in. But then you get this rebound, and the world begins to warm again. The ice begins to melt, and there’s a second pulse of extinction.

Earth has two roughly stable states. You’ve got the icehouse world, which we are in at the moment, where there is permanent ice at the poles. And then you have greenhouse Earth, where there is no permanent ice at the poles. Life is currently not really adapted to a greenhouse world. Humans — and I mean all hominins, all great apes — have never experienced the greenhouse world.

You write that we shouldn’t become despondent, which is easy to do when you’re faced with forces that affect life on a planetary scale. What should we do instead?

The problem with despondency is it leads to inaction. There’s a poem which I really like by Piet Hein:

Eradicate the optimist
who takes the easy view
that human values will persist
no matter what we do.
Annihilate the pessimist
whose ineffectual cry
is that the goal’s already missed
however hard we try.

The point is that we cannot sit back. It’s never too late. The sooner we act, the more we save, but there’s always something else to save.

If this is a mass extinction that we are causing right now, life will rebound and eventually be as diverse as it is today. But this is our world. We are here, and there are wonderful creatures around today. There are wonderful landscapes and wonderful plants. And I think it’s a shame to throw it away. If we undergo a huge period of transition, usher in a new age where life is fundamentally different, then we’re less likely to be a part of it. So we should protect the world that is our land, our part of geological time.

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Rocket Lab’s CAPSTONE mission to the moon is key to establishing a lunar space station – TechCrunch



It may look like Rocket Lab is just launching a microwave-sized hunk of metal to the moon — but it’s crucial for our future in space

“Going to the moon is no joke.” So said Rocket Lab CEO Peter Beck, just days before the planned launch of CAPSTONE, a watershed mission for both NASA and the private space industry.

The mission is important, though you might not assume so based on the stats of the CAPSTONE CubeSat on its own: It’s about the size of a microwave oven and weighs in at just 55 pounds. But the end goal of the spacecraft’s roughly six-month stint in lunar orbit is to chart a favorable trajectory for a crewed station that will orbit the moon. Once established, that platform, dubbed Gateway, could unlock a whole new chapter in human space exploration.

Consider CAPSTONE (which stands for Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment) the first in-space step in NASA’s Artemis program, an ambitious plan to return humans to the moon by the middle of this decade. The Gateway platform could be used as a way station for lunar landers, a resupply junction for astronauts exploring the moon — or even a transfer point for missions to Mars and beyond.

Image Credits: NASA

The mission isn’t just a big deal for the Artemis program and public space exploration: Notably, it’s the result of a patchwork of collaboration between private industry and the space agency. The list of partners on NASA’s website for the mission includes:

And, of course, Rocket Lab for the launch services.

CAPSTONE is launching aboard a Rocket Lab Electron rocket from the company’s site on New Zealand’s remote Māhia Peninsula. “This is the highest mass and the highest performance Electron has ever had to fly by quite some margin,” Beck said. “The vehicle is absolutely stretched to its limits with respect to performance.”

In addition to actually launching the mission, Rocket Lab developed a special variant of its Photon spacecraft for this endeavor, which it’s calling the Lunar Photon. That spacecraft will conduct a series of orbits over a period of around six to eight days, increasing the velocity and apogee of the orbit over time. Then, Photon will perform the final burn, called the trans-lunar injection, which will set it on its course to the moon. Around 20 minutes after the injection, Photon and CAPSTONE will separate and the CubeSat alone will conduct the remaining maneuvers to reach its target orbit around the moon.

“The moon is a long way away,” Beck said, referring to the complexities of Photon’s maneuvers. “You’re traveling at huge velocities. So it only takes a smallest fraction of an angle error or a velocity error, and you just shoot way past where you need to be.”

“It’s like firing a bullet millions of kilometers, and it’s got to be exactly in the right place.”

An unusual orbit

The exact orbit that CAPSTONE will be exploring is called a near-rectilinear halo orbit (NRHO). That orbit, in the shape of a necklace, will bring CAPSTONE as close as 1,000 miles to the moon’s surface and as far away as 40,000 miles. Although the shape is odd, it’s a very stable orbit, which means greater efficiency and less use of propellant. NRHO was up against competing orbits, including low lunar orbit and distant retrograde orbit, as the ideal trajectory for Gateway; but as NASA explains, NRHO is a “best of both worlds” option that’ll provide astronauts with easy access to the lunar surface, a continuous line of sight to (and communication with) Earth and access to deep space.

But testing the NRHO orbit is not the only point of the mission. The CubeSat will also help NASA understand navigation, or how to generate an accurate estimation of Gateway’s trajectory, and station-keeping.

“Because the NRHO is marginally stable, Gateway and CAPSTONE will both require a gentle ‘nudge’ about once a week to stay in orbit,” Ethan Kayser, CAPSTONE mission design lead at Advanced Space, explained in a Reddit post. “CAPSTONE will be using the same strategy to design and execute these stationkeeping maneuvers, which occur once each revolution.” The eight propulsion thrusters built by Stella Exploration will be key to conducting these maneuvers.

CAPSTONE will arrive at its lunar orbit on November 13. After a roughly six-month orbital mission, NASA plans to crash the spacecraft into the moon at the end of its life. The launch is set to take place during an instantaneous launch window at 5:55 AM EDT on Tuesday, June 28, so be sure to follow TechCrunch for live coverage and reporting on the outocome of the mission launch.

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See A Jaw-Dropping Crescent Moon, 50 Meteors And Hour And Our Billion-Star Milky Way: What You Can See In The Night Sky This Week – Forbes



Each Monday I pick out the northern hemisphere’s celestial highlights (mid-northern latitudes) for the week ahead, but be sure to check my main feed for more in-depth articles on stargazing, astronomy, eclipses and more.

What To See In The Night Sky This Week: June 27-July 3, 2022

It’s not easy going stargazing in summer at this time of year in the northern hemisphere. The nights are just so short. The best reason to stay up late and go somewhere dark is the sight of the spiral arms of our Milky Way galaxy arcing across the night sky. Look to the southeast and south for that this month—and this week in particular, which will be largely moonless.

When our satellite does emerge from its New Moon conjunction with the Sun expect lush views of a slender crescent Moon. Who said summer was no good for stargazing?

Monday, June 27, 2022: Boötids meteor shower and a crescent Moon meets Mercury

The June Boötids meteor shower—occasionally called the June Draconids or Boötid-Draconids meteor shower—runs annually between June 22 and July 2, but peaks in the early hours of June 27, 2020.

If you are out stargazing late tonight keep an eye out for the 50 or so “shooting stars” per hour expected. The shower’s radiant point—the apparent source of the shooting stars—is the constellation of Boötes.

If you’re still up before dawn you might just catch the planet Mercury just 3.9º from an incredibly slender 2.6% crescent Moon, but be very careful if you use binoculars to help you because the rising Sun is NOT something you want in your field of view.

Tuesday, June 30, 2022: A super-slim crescent Moon and ‘Asteroid Day’

Today is Asteroid Day. With any luck there won’t be anything to see hurtling towards (or even smashing into) our planet, but it’s a good chance to consider the threat posed to Earth of incoming space rocks. What’s really going to change everything is the Vera Rubin Observatory, which from 2022 will deploy a wide-angle camera to map the night sky in real-time—and identify many thousands of hitherto unfound asteroids.

Friday, July 1, 2022: ‘Earthshine’ on a crescent Moon

You should get a much clearer view of a crescent Moon today. Now 8% illuminated, in a clear sky it will be a stunning sight, not least because you’ll be able to see sunlight being reflected onto the Moon by the Earth as “Earthshine” or “planet-shine.” It’s a subtle sight, but once seen cannot be unseen; look at the Moon’s darkened limb with your eyes, or better still, with a pair of binoculars, to appreciate this fine sight.

As a bonus it will be just 3.5° from the Beehive Cluster, though you’ll need a pair of binoculars to see its 30 or so easily visible stars.

Saturday, July 2, 2022: ‘Earthshine’ on a crescent Moon and Regulus

Tonight just after sunset look west for a 14% crescent Moon, once again displaying Earthshine. The stars around it will be those of the “sickle” in the constellation of Leo. The brightest, about 5º left of the Moon, will be Leo’s brightest star, Regulus. It’s one of the brightest stars in the night sky and about 78 light-years distant.

Object of the week: noctilucent clouds

This time of year the twilight seems to last forever at northerly latitudes so consider looking for a “ghostly” display of noctilucent or “night shining” clouds (NLCs). At their best in northern twilight skies during June and July (at latitudes between 50° and 70° north and south of the equator), NLCs are very delicate high altitude clouds of icy dust that form about 50 miles/80 kilometres up. Because the Sun is never too far below the horizon at these latitudes they get subtly lit up for a short time. They’re best seen with the naked eye or a pair of binoculars.

Wishing you clear skies and wide eyes.

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Astronomers Found a Crater From The Mystery Rocket That Smashed Into The Moon – ScienceAlert



The Lunar Reconnaissance Orbiter (LRO) – NASA’s eye-in-the-sky in orbit around the Moon – has found the crash site of the mystery rocket booster that slammed into the far side of the Moon back on 4 March 2022.

The LRO images, taken May 25th, revealed not just a single crater, but a double crater formed by the rocket’s impact, posing a new mystery for astronomers to unravel.

Why a double crater? While somewhat unusual – none of the Apollo S-IVBs that hit the Moon created double craters – they’re not impossible to create, especially if an object hits at a low angle. But that doesn’t seem to be the case here.

Astronomer Bill Gray, who first discovered the object and predicted its lunar demise back in January, explains that the booster “came in at about 15 degrees from vertical. So that’s not the explanation for this one.”

The impact site consists of an 18-meter-wide eastern crater superimposed on a 16-meter-wide western crater. Mark Robinson, Principal Investigator of the LRO Camera team, proposes that this double crater formation might result from an object with distinct, large masses at each end.

Before (2022-02-28) and after image (2022-05-21) of the Moon. (NASA/GSFC/Arizona State University)

“Typically a spent rocket has mass concentrated at the motor end; the rest of the rocket stage mainly consists of an empty fuel tank. Since the origin of the rocket body remains uncertain, the double nature of the crater may help to indicate its identity,” he said.

So what is it?

It’s a long story. The unidentified rocket first came to astronomers’ attention earlier this year when it was identified as a SpaceX upper stage, which had launched NASA’s Deep Space Climate Observatory (DSCOVR) to the Sun-Earth L1 Lagrange Point in 2015.

Gray, who designs software that tracks space debris, was alerted to the object when his software pinged an error. He told The Washington Post on January 26 that “my software complained because it couldn’t project the orbit past March 4, and it couldn’t do it because the rocket had hit the Moon.”

Gray spread the word, and the story made the rounds in late January – but a few weeks later, he received an email from Jon Giorgini at the Jet Propulsion Lab (JPL).

Giorgini pointed out that DSCOVR’s trajectory shouldn’t have taken the booster anywhere near the Moon. In an effort to reconcile the conflicting trajectories, Gray began to dig back into his data, where he discovered that he had misidentified the DSCOVR booster way back in 2015.

SpaceX wasn’t the culprit after all. But there was definitely still an object hurtling towards the Moon. So what was it?

A bit of detective work led Gray to determine it was actually the upper stage of China’s Chang’e 5-T1 mission, a 2014 technology demonstration mission that lay the groundwork for Chang’e 5, which successfully returned a lunar sample to Earth in 2020 (incidentally, China recently announced it would follow up this sample return mission with a more ambitious Mars sample return project later this decade). 

Jonathan McDowell offered some corroborating evidence that seemed to bolster this new theory for the object’s identity.

The mystery was solved.

Except, days later, China’s Foreign Minister claimed it was not their booster: it had deorbited and crashed into the ocean shortly after launch.

As it stands now, Gray remains convinced it was the Change 5-T1 booster that hit the Moon, proposing that the Foreign Minister made an honest mistake, confusing Chang’e 5-T1 with the similarly named Chang’e 5 (whose booster did indeed sink into the ocean).

As for the new double crater on the Moon, the fact that the LRO team was able to find the impact site so quickly is an impressive feat in itself. It was discovered mere months after impact, with a little help from Gray and JPL, who each independently narrowed the search area down to a few dozen kilometers.

For comparison, The Apollo 16 S-IVB impact site took more than six years of careful searching to find.

Bill Gray’s account of the booster identification saga is here, as well as his take on the double crater impact. The LRO images can be found here.

This article was originally published by Universe Today. Read the original article.

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