How old were you when you learned that the Moon in the Southern Hemisphere is upside down? I was today years old…this is my head exploding โ> %@*&!$. Ok, the Moon isn’t upside down (that’s Northern-ist) but its orientation changes depending on if you’re north or south of the equator.
“From our perspective, the Moon and the night sky is actually rotated 180 degrees compared to our Northern Hemispherical friends,” Jake Clark, an astronomer from the University of Southern Queensland in Australia, explained to ScienceAlert.
“In the south we see the Moon’s dark ‘Oceanus Procellarum’ sea in the south-east corner compared to in the north-west corner for a northern observer.”
But why does it look like this? Well, because physically, we’re actually upside down compared to someone standing in the opposite hemisphere.
That makes perfect sense & the explanation is quite simple but it’s still messing with my head. How did I not know this? Here’s how the Moon appears in the Northern Hemisphere (from Wikipedia):
This puzzle is based on an icosahedral map projection and has the topology of a sphere. This means it has no edges, no North and South, and no fixed shape. Try to get the landmasses together or see how the oceans are connected. Make your own maps of the earth!
This is easily the most awe-inspiring and jaw-dropping thing I’ve seen in months. In its low Earth orbit ~250 miles above our planet, the International Space Station takes about 90 minutes to complete one orbit of the Earth. Fewer than 600 people have ever orbited our planet, but with this realtime video by Seรกn Doran, you can experience what it looks like from the vantage point of the IIS for the full 90 minutes.
The video is in 4K so find the largest monitor/TV you can, turn up the sound, watch for awhile (even if it’s only for a few minutes), and see if you don’t experience a little bit of the Overview Effect, what NASA astronaut Kathryn Sullivan described as a life-altering experience:
I first saw the earth โ the whole earth โ from the shuttle Challenger in 1984. The view takes your breath away and fills you with childlike wonder. An incredibly beautiful tapestry of blue and white, tan, black and green seems to glide beneath you at an elegant, stately pace. But you’re actually going so fast that the entire map of the world spins before your eyes with each 90-minute orbit. After just one or two laps, you feel, maybe for the first time, like a citizen of a planet.
In 1968, the crew of Apollo 8 became the first ever humans to leave the cozy confines of Earth orbit. From Wikipedia:
The three-astronaut crew โ Commander Frank Borman, Command Module Pilot James Lovell, and Lunar Module Pilot William Anders โ became the first humans to travel beyond low Earth orbit; see Earth as a whole planet; enter the gravity well of another celestial body (Earth’s moon); orbit another celestial body (Earth’s moon); directly see the far side of the Moon with their own eyes; witness an Earthrise; escape the gravity of another celestial body (Earth’s moon); and re-enter the gravitational well of Earth.
That’s a substantial list of firsts. But before setting out on the mission, neither the crew or anyone else at NASA gave much thought to perhaps the most significant and long-lasting achievements on that list: “see Earth as a whole planet” and “witness an Earthrise”. In this gem of a short film by Emmanuel Vaughan-Lee, Anders, Borman, and Lovell recall what it was like for them to be the first of only 24 people to see, with their own eyes, the Earth from that distance, a blue marble hanging in the inky blackness of space.
What they should have sent was poets, because I don’t think we captured the grandeur of what we’d seen.
Men’s conception of themselves and of each other has always depended on their notion of the earth. When the earth was the World โ all the world there was โ and the stars were lights in Dante’s heaven, and the ground beneath men’s feet roofed Hell, they saw themselves as creatures at the center of the universe, the sole, particular concern of God โ and from that high place they ruled and killed and conquered as they pleased.
And when, centuries later, the earth was no longer the World but a small, wet spinning planet in the solar system of a minor star off at the edge of an inconsiderable galaxy in the immeasurable distances of space โ when Dante’s heaven had disappeared and there was no Hell (at least no Hell beneath the feet) โ men began to see themselves not as God-directed actors at the center of a noble drama, but as helpless victims of a senseless farce where all the rest were helpless victims also and millions could be killed in world-wide wars or in blasted cities or in concentration camps without a thought or reason but the reason โ if we call it one โ of force.
Now, in the last few hours, the notion may have changed again. For the first time in all of time men have seen it not as continents or oceans from the little distance of a hundred miles or two or three, but seen it from the depth of space; seen it whole and round and beautiful and small as even Dante โ that “first imagination of Christendom” โ had never dreamed of seeing it; as the Twentieth Century philosophers of absurdity and despair were incapable of guessing that it might be seen. And seeing it so, one question came to the minds of those who looked at it. “Is it inhabited?” they said to each other and laughed โ and then they did not laugh. What came to their minds a hundred thousand miles and more into space โ “half way to the moon” they put it โ what came to their minds was the life on that little, lonely, floating planet; that tiny raft in the enormous, empty night. “Is it inhabited?”
The medieval notion of the earth put man at the center of everything. The nuclear notion of the earth put him nowhere โ beyond the range of reason even โ lost in absurdity and war. This latest notion may have other consequences. Formed as it was in the minds of heroic voyagers who were also men, it may remake our image of mankind. No longer that preposterous figure at the center, no longer that degraded and degrading victim off at the margins of reality and blind with blood, man may at last become himself.
To see the earth as it truly is, small and blue and beautiful in that eternal silence where it floats, is to see ourselves as riders on the earth together, brothers on that bright loveliness in the eternal cold โ brothers who know now they are truly brothers.
This is fun to play with: Dinosaur Pictures has a Google Earth-style globe that shows the state of the planet at various intervals 20 million, 200 million, or 750 million years ago, with plenty of stops in between. You can watch India collide into the rest of Asia, or jump to the birth (and death) of dinosaurs, the first flowers, the first hominids, etc. And you can watch the whole planet or zero in on an individual contemporary address.
One point of view that I found oddly soothing: the middle of the Pacific Ocean. All over the planet, millions of years are passing by, transforming the land-bound flora and fauna through tectonic and climatic upheavals, and the ocean just… stays the ocean. Big things are happening below the surface, but the biggest part of the planet just continues to be this deep blue, undisturbed marble.
Humans are so small compared to the size of the Earth, it’s sometimes difficult to comprehend the scale of things like, say, the massive meteorite that struck the Yucatan peninsula about 66 million years ago, an event that triggered the mass extinction of plants and animals, including the dinosaurs. In his recent book, The Ends of the World, Peter Brannen takes a crack at explaining just how big the meteorite was and how quickly the event occurred.
“The meteorite itself was so massive that it didn’t notice any atmosphere whatsoever,” said Rebolledo. “It was traveling 20 to 40 kilometers per second, 10 kilometers โ probably 14 kilometers โ wide, pushing the atmosphere and building such incredible pressure that the ocean in front of it just went away.”
These numbers are precise without usefully conveying the scale of the calamity. What they mean is that a rock larger than Mount Everest hit planet Earth traveling twenty times faster than a bullet. This is so fast that it would have traversed the distance from the cruising altitude of a 747 to the ground in 0.3 seconds. The asteroid itself was so large that, even at the moment of impact, the top of it might have still towered more than a mile above the cruising altitude of a 747. In its nearly instantaneous descent, it compressed the air below it so violently that it briefly became several times hotter than the surface of the sun.
“The pressure of the atmosphere in front of the asteroid started excavating the crater before it even got there,” Rebolledo said. “Then when the meteorite touched ground zero, it was totally intact. It was so massive that the atmosphere didn’t even make a scratch on it.”
Unlike the typical Hollywood CGI depictions of asteroid impacts, where an extraterrestrial charcoal briquette gently smolders across the sky, in the Yucatan it would have been a pleasant day one second and the world was already over by the next. As the asteroid collided with the earth, in the sky above it where there should have been air, the rock had punched a hole of outer space vacuum in the atmosphere. As the heavens rushed in to close this hole, enormous volumes of earth were expelled into orbit and beyond โ all within a second or two of impact.
“So there’s probably little bits of dinosaur bone up on the moon,” I asked.
“Yeah, probably.”
I don’t know if your eyes are as wide as mine are about now but…
Once a matter of debate, we know today the Earth is not flat. But the satellite imagery we’re most familiar with โ taken straight down โ flattens and obscures the visual cues we get from perspective, making the imagery appear like maps, not photos.
Take for example this nadir view of Monte Fitz Roy. You might not appreciate that these are mountains unless you spot the clue in the jagged shadows coming off the mountain’s serrated summits.
When you take an image of Monte Fitz Roy from an angle, the view becomes altogether different: the mountains rise to their commanding height, valleys regain their depth, and background features recede into the distance. It’s like getting a view out the window of an airplane 450 kilometers high.
The turn of the century doesn’t seem all that long ago, but here we are starting our 18th year of the 21st century already.1 The pace of human activity since the Renaissance is itself increasing. For instance, David Wallace-Wells pointed out:
Whatever you may think about the pace of climate change, it is happening mind-bendingly fast, almost in real time. It is not just that December wildfires were unheard of just three decades ago. We have now emitted more carbon into the atmosphere since Al Gore wrote his first book on climate than in the entire preceding history of humanity, which means that we have engineered most of the climate chaos that now terrifies us in that brief span.
Numbered decades, centuries, and millennia all start on years ending in “1”. This is because the first century AD starts on Jan 1, 1…there was no year 0. So, the first day of the 21st century is Jan 1, 2001, not Jan 1, 2000 like the article states. This is confusing because the 1800s and the 19th century are almost, but not exactly, the same thing.โฉ
In her book The Sixth Extinction, Elizabeth Kolbert warns that we are in the midst of the Earth’s sixth mass extinction of life, this time caused by humans.
Over the last half a billion years, there have been five mass extinctions, when the diversity of life on earth suddenly and dramatically contracted. Scientists around the world are currently monitoring the sixth extinction, predicted to be the most devastating extinction event since the asteroid impact that wiped out the dinosaurs. This time around, the cataclysm is us.
This is a mainstream view of humanity’s effect on the Earth flora and fauna…for evidence, you don’t need to look any further than all of the large mammal species that have gone extinct or are endangered because of human activity.
A more controversial take is offered by Chris Thomas in his recent book, Inheritors of the Earth: How Nature Is Thriving in an Age of Extinction. Thomas allows that there’s a “mini mass extinction” happening, but he also argues that the extreme evolutionary pressure brought by our increasing dominance of our planet’s ecosystems will result in a “sixth mass genesis”, a dramatic increase in the Earth’s biodiversity.
Human cities and mass agriculture have created new places for enterprising animals and plants to live, and our activities have stimulated evolutionary change in virtually every population of living species. Most remarkably, Thomas shows, humans may well have raised the rate at which new species are formed to the highest level in the history of our planet.
Drawing on the success stories of diverse species, from the ochre-colored comma butterfly to the New Zealand pukeko, Thomas overturns the accepted story of declining biodiversity on Earth. In so doing, he questions why we resist new forms of life, and why we see ourselves as unnatural. Ultimately, he suggests that if life on Earth can recover from the asteroid that killed off the dinosaurs, it can survive the onslaughts of the technological age.
The history of life on Earth is a history of extinctions and ecological failures, but it is also a story of formation of new forms and spread of those new forms around the world. The net result has been a gain in diversity. In the human era we are seeing great losses, but we are also seeing all these biological gains of new animals and plants spreading around the world, new hybrids coming into existence. I am not saying there is yet a balance between the two. I accept the losses, but it is also scientifically, and in terms of our human attitudes to nature, extremely interesting to contemplate the gains simultaneously.
If the processes that are going on at the moment continue for a very long time, it is my expectation that the number of species on Earth will grow enormously. We are moving species of existing animals and plants back and forth across the world, so that they are all arriving in new geographic regions. We know when species have done this in the ancient past, they have turned into new species in those different regions. If you fast-forward a million years or a few million years, all of these introduced species that leave surviving descendants will have turned into new species. And that is going to generate many more species. We have effectively created a massive species generator.
That certainly does put an interesting spin on extinction and invasive species.
Having achieved spectacular success with Planet Earth II, the BBC and David Attenborough are revisiting another of their previous nature documentaries, the 2001 series The Blue Planet, “a comprehensive series on the natural history of the world’s oceans”. Blue Planet II, Attenborough promises, will use new technology and our increased understanding of the natural world to great advantage in telling the story of the animal and plant life โ dancing yeti crabs! dolphins spitting to trick prey! TurtleCam! โ that dwells in our oceans.
The score is by Hans Zimmer, who also collaborated with Radiohead to rework an old song of theirs for the series. Bloom, off of King of Limbs, was originally inspired by the first Blue Planet series, so it’s come full circle with its inclusion in the new series. Vox examines how Zimmer and the band adapted the song:
If you listen closely enough to Radiohead and Hans Zimmer’s rework of “Bloom” for Blue Planet II, you can hear a really fascinating orchestral trick at work. They call it the “tidal orchestra” โ it’s a musical effect created by instructing each player to play their notes only if the person next to them isn’t playing. The result is a randomly swelling and fading musical bed for the entire series that captures the feeling of ocean waves. It’s a captivating way to score a soundtrack for the ocean โ but it also fits in with a long history of capturing randomness in music composition.
The “tidal orchestra” technique was inspired by pointillism and randomness: using small individual sounds to build a soundscape rather than starting with a specific tune. For some reason, it also reminds me of Sol LeWitt’s Wall Drawing 797. (No idea what inspired Yorke’s pants though. MC Hammer? Wow.)
Planet Earth II was probably my favorite movie/show/media from the past year, so I am really looking forward to Blue Planet II.
Kurzgesagt asks and answers the question: what happens if we bring the Sun to the Earth? Since the density and makeup of the Sun varies, they go over scenarios of sampling a house-size chunk from four different spots of the Sun: the chromosphere, the photosphere, the radiative zone, and the core. The answers range from “not much” to “well, that was a terrifically bad idea”.
On March 8-9, 2016, a total solar eclipse swept across the Pacific Ocean for more than 5 hours. About a year before the eclipse, Hayden Planetarium astronomer Joe Rao realized Alaska Airlines flight 870 from Anchorage to Honolulu would pass right through the path of totality…but 25 minutes too early. Rao called the airline and convinced them to shift the flight time.
Alaska’s fleet director, Captain Brian Holm, reviewed the proposed flight path and possible in-route changes to optimize for the eclipse. The schedule planning team pushed back the departure time by 25 minutes, to 2 p.m.
On the day of the flight, Dispatch will develop the specific flight plan, to find the most efficient route and account for weather and wind. Maintenance and maintenance control will help make sure the plane is ready to go โ they even washed all the windows on the right side of the plane.
Captain Hal Andersen also coordinated with Oceanic Air Traffic Control, to make them aware that the flight might require a few more tactical changes then normal.
“The key to success here is meeting some very tight time constraints โ specific latitudes and longitudes over the ocean,” Andersen said. “With the flight management computer, it’s a pretty easy challenge, but it’s something we need to pay very close attention to. We don’t want to be too far ahead or too far behind schedule.”
July 11, 2010. That was the eclipse over Easter Island, the one for which hotel room rates were so high that there was no way Kentrianakis could afford it. Instead, he considered attempting a trip to Argentina, where experts predicted there was a 5 percent chance of clear skies. His wife at the time, Olga, urged him not to go โ it’s not worth the expense, she insisted. Reluctantly, Kentrianakis stayed home.
“It was the beginning of the end for us,” Kentrianakis says. There were problems in the marriage before that episode, “but it affected me that I felt that she didn’t really appreciate what I loved.” They were divorced the following year.
Kentrianakis doesn’t like to dwell on this, or the other things he’s given up to chase eclipses. He knows his bosses grumbled about the missed days of work. Friends raise their eyebrows at the extremes to which he goes. He’s unwilling to admit how much he’s spent on his obsession.
“There is a trade-off for everything, for what somebody wants,” he says.
For this year’s eclipse, Alaska Airlines is doing a special charter flight for astronomy nerds and eclipse chasers. Depending on how this eclipse goes, seeing an eclipse from an airplane might be on my bucket list for next time. (via @coudal)
Timeline of the far future is one of my favorite pages on Wikipedia. It details what might happen to humanity, human artifacts, the Earth, the solar system, and the Universe from 10,000 years from now until long past the heat death of the Universe. Information is Beautiful has made a lovely infographic of the timeline.
Reading through the timeline is a glorious way to spend time…here are a few favorites I noticed this time around as well as some from my first post.
August 20, 10,663: “A simultaneous total solar eclipse and transit of Mercury.”
20,000 years: “The Chernobyl Exclusion Zone, the 1,000 sq mi area of Ukraine and Belarus left deserted by the 1986 Chernobyl disaster, becomes safe for human life.”
296,000 years: “Voyager 2 passes within 4.3 light-years of Sirius, the brightest star in the night sky.”
1 million years: “Highest estimated time until the red supergiant star Betelgeuse explodes in a supernova. The explosion is expected to be easily visible in daylight.”
1 million years: “On the Moon, Neil Armstrong’s ‘one small step’ footprint at Tranquility Base will erode by this time, along with those left by all twelve Apollo moonwalkers, due to the accumulated effects of space weathering.”
15.7 million: “Half-life of iodine-129, the most durable long-lived fission product in uranium-derived nuclear waste.”
100 million years: “Future archaeologists should be able to identify an ‘Urban Stratum’ of fossilized great coastal cities, mostly through the remains of underground infrastructure such as building foundations and utility tunnels.”
1 billion years: “Estimated lifespan of the two Voyager Golden Records, before the information stored on them is rendered unrecoverable.”
4 billion years: “Median point by which the Andromeda Galaxy will have collided with the Milky Way, which will thereafter merge to form a galaxy dubbed ‘Milkomeda’.”
7.59 billion years: The Earth and Moon are very likely destroyed by falling into the Sun, just before the Sun reaches the tip of its red giant phase and its maximum radius of 256 times the present-day value. Before the final collision, the Moon possibly spirals below Earth’s Roche limit, breaking into a ring of debris, most of which falls to the Earth’s surface.
100 billion years: “The Universe’s expansion causes all galaxies beyond the Milky Way’s Local Group to disappear beyond the cosmic light horizon, removing them from the observable universe.”
In a meditative video for the NY Times, Dennis Overbye takes us on a tour of eclipses that happen in our solar system and beyond.
On the 21st day of August, 2017, the moon will slide between the Earth and the sun, painting a swath of darkness across North America. The Great American Solar Eclipse. An exercise in cosmic geometry. A reminder that we live on one sphere among many, all moving to the laws of Kepler, Newton and Einstein.
Humans have many more vantage points from which to observe solar eclipses than when the last solar eclipse occurred in the US in 1979. I had no idea that the Mars rovers had caught partial solar eclipses on Mars…so cool. (via @jossfong)
If the earth were to suddenly flatten, presumably all sorts of hell would break loose. I guess it would depend on how flat is flat. If we’re talking pancake flat, gravity would be an immediate problem: gravitational attraction goes as G(m1*m2)/r^2, where G is the gravitational constant, m1 & m2 are two masses, and r is distance. A sphere is the 3D shape that maximizes surface area relative to volume, which kind of gives gravity the biggest bang for its buck. If you flatten the sphere, the far side gets closer to the new center point, but the ends spread way out, so surface gravity goes down at the center, and way down at the edges. Lose gravity and bye-bye atmosphere.
Other first-order problems: heat, radioactivity, etc. In our spherical earth, both of these are concentrated in the core. If the earth were flattened, they would have to go somewhere-presumably a lot closer to the surface.
Flat-Earthers aside, people have known that the Earth is round since at least the 3rd century BC. This quick video explores a few of the ways we know the world is spherical, some of them quite simple to recreate as experiments. See also Top 10 Ways to Know the Earth is Not Flat.
(5) Seeing Farther from Higher
Standing in a flat plateau, you look ahead of you towards the horizon. You strain your eyes, then take out your favorite binoculars and stare through them, as far as your eyes (with the help of the binocular lenses) can see.
Then, you climb up the closest tree โ the higher the better, just be careful not to drop those binoculars and break their lenses. You then look again, strain your eyes, stare through the binoculars out to the horizon.
The higher up you are the farther you will see. Usually, we tend to relate this to Earthly obstacles, like the fact we have houses or other trees obstructing our vision on the ground, and climbing upwards we have a clear view, but that’s not the true reason. Even if you would have a completely clear plateau with no obstacles between you and the horizon, you would see much farther from greater height than you would on the ground.
This phenomena is caused by the curvature of the Earth as well, and would not happen if the Earth was flat.
Update: Carl Sagan explains how Greek astronomer and mathematician Eratosthenes figured out how the Earth was round in ~200 BC.
Since life first formed on Earth billions of years ago, the ability of organisms to use more powerful and efficient energy sources has been key in driving the diversity and complexity of life. According to this provocative piece in Nature by Olivia Judson, the history of life on Earth can be divided into five energetic epochs characterized by the following energy sources: geochemical energy, sunlight, oxygen, flesh and fire.
The first two were present at the start, but oxygen, flesh and fire are all consequences of evolutionary events. Since no category of energy source has disappeared, this has, over time, resulted in an expanding realm of the sources of energy available to living organisms and a concomitant increase in the diversity and complexity of ecosystems. These energy expansions have also mediated the transformation of key aspects of the planetary environment, which have in turn mediated the future course of evolutionary change. Using energy as a lens thus illuminates patterns in the entwined histories of life and Earth, and may also provide a framework for considering the potential trajectories of life-planet systems elsewhere.
Organisms formed on Earth and changed the planet, which led to the formation of new organisms more suited to the new environment. For instance, when a type of bacteria evolved to turn sunshine into oxygen, it completely changed the planet.
In the absence of a biotic source of oxygen, trace quantities of the gas can be generated abiotically: water molecules can be split by sunlight or radioactive decay. However, these abiotic processes are much less efficient than their biotic equivalent. Had cyanobacteria, or something like them, never evolved, oxygen would never have built up in the atmosphere of the Earth.
But build up it did. Between 2.45 and 2.32 Ga, significant quantities of oxygen began to accumulate in the air, an episode known as the Great Oxidation Event. Before the Great Oxidation, atmospheric oxygen levels were less than 10^-5 of the present atmospheric level of ~21%. By ~2 Ga, they had risen to perhaps 0.1-1% of the present atmospheric level. Although the subsequent history of oxygen is complex and many details are uncertain, Earth’s atmosphere has contained an appreciable level of the gas ever since. (Full oxygenation of the oceans, however, would not happen until around 1.8 billion years after the Great Oxidation.)
The original piece in Nature is fairly readable for a science journal, but this summary in The Atlantic is worth a look if you’re short on time or attention. (via @CharlesCMann)
Today they are releasing a new global composite map of night lights as observed in 2016, as well as a revised version of the 2012 map. The NASA group has examined the different ways that light is radiated, scattered and reflected by land, atmospheric and ocean surfaces. The principal challenge in nighttime satellite imaging is accounting for the phases of the moon, which constantly varies the amount of light shining on Earth, though in predictable ways. Likewise, seasonal vegetation, clouds, aerosols, snow and ice cover, and even faint atmospheric emissions (such as airglow and auroras) change the way light is observed in different parts of the world. The new maps were produced with data from all months of each year. The team wrote code that picked the clearest night views each month, ultimately combining moonlight-free and moonlight-corrected data.
Scientists are planning on providing “daily, high-definition views of Earth at night” starting later this year. It’s worth clicking through to play with the interactive India map…it’s astounding to see how much light the country has added in the past 5 years. And see if you can spot North Korea at night:
25 people would be 0-14 years old
31 would be Christian
23 would be Muslim
15 would be Hindu
6 would speak Spanish
5 would speak English
54 would be urban dwellers
11 would live on less than $1.90 USD per day
95 live in an area with a mobile-cellular network
And some that are not on that page:
1 person would die every 15 months
2 people would be born every 6 months
1350 people would have died, all-time
Sometimes big distances, long time periods, and large numbers can be difficult to grasp. So it helps to contextualize them with comparisons. When you do so, you realize that a billion is much much more than a million:
But when he linked these numbers to time, it brought things in perspective: 1 million seconds is nearly 12 days, whereas 1 billion seconds is almost 32 years. “Everybody gets it when you say it like that,” he wrote in an email. “If you just said 1 billion is three orders of magnitude greater than 1 million, I don’t think it would make the same impression.”
Tim Urban’s Life Calendar emphasizes the relative shortness of human life and the importance of using your time well by reorganizing a human lifespan into weeks.
Each row of weeks makes up one year. That’s how many weeks it takes to turn a newborn into a 90-year-old.
It kind of feels like our lives are made up of a countless number of weeks. But there they are โ fully countable โ staring you in the face.
You want to talk about human insignificance? If Betelgeuse, one of the largest stars shown in the video, were in the Sun’s place, it would nearly reach the orbit of Jupiter, from which light takes 43 minutes (on average) to reach the Earth. (via @stevesilberman)
From James Lovelock, The Earth and I is a look at our planet and the living things on it…how Earth came to be, what we understand about our planet, and how we live today. Lisa Randall, Martin Rees, Edward O. Wilson, and Eric Kandel have contributed writing to the book.
I reported back in February that the BBC was doing another season of Planet Earth with David Attenborough (aka the voice of nature). Now there’s a trailer out (with a Sigur Ros soundtrack) and the show is set to debut in the UK on BBC One later this month. In US? Who knows… probably in 8 months with Ellen Degeneres narrating.
Update: Planet Earth II, a massive hit in Britain already, will debut on US television tomorrow (Feb 18). You can catch the first episode on AMC, BBC America, and Sundance TV. And unlike the original Planet Earth, they’ve thankfully kept the original Attenborough narration for the US version of Planet Earth II.
NASA recently released a time lapse video of the Earth constructed from over 3000 still photographs taken over the course of a year. The photos were taken by a camera mounted on the NOAA’s DSCOVR satellite, which is perched above the Earth at Lagrange point 1.
Wait, have we talked about Lagrange points yet? Lagrange points are positions in space where the gravity of the Sun and the Earth (or between any two large things) cancel each other out. The Sun and the Earth pull equally on objects at these five points.
L1 is about a million miles from Earth directly between the Sun and Earth and anything that is placed there will hover there relative to the Earth forever (course adjustments for complicated reasons aside). It is the perfect spot for a weather satellite with a cool camera to hang out, taking photos of a never-dark Earth. In addition to DSCOVR, at least five other spacecraft have been positioned at L1.
L2 is about a million miles from the Earth directly opposite L1. The Earth always looks dark from there and it’s mostly shielded from solar radiation. Five spacecraft have lived at L2 and several more are planned, including the sequel to the Hubble Space Telescope. Turns out that the shadow of the Earth is a good place to put a telescope.
L3 is opposite the Earth from the Sun, the 6 o’clock to the Earth’s high noon. This point is less stable than the other points because the Earth’s gravitational influence is very small and other bodies (like Venus) periodically pass near enough to yank whatever’s there out, like George Clooney strolling through a country club dining room during date night.
And quoting Wikipedia, “the L4 and L5 points lie at the third corners of the two equilateral triangles in the plane of orbit whose common base is the line between the centers of the [Earth and Sun]”. No spacecraft have ever visited these points, but they are home to some interplanetary dust and asteroid 2010 TK7, which orbits around L4. Cool! (via slate)
About a hundred years ago, a tiny asteroid making its way around the sun got caught in Earth’s gravity well. Now it’s locked in an irregular orbit far around our planet, between 38 and 100 times the distance between the Earth and its proper moon.
As it orbits the sun, asteroid 2016 HO3 spends about half of the time closer to the sun than Earth, and passes ahead of our planet. The other half of the time it falls behind.
It’s also in a tilted orbit, which causes it to weave up and down on the orbital plane like a bob on choppy waters. As NASA’s Paul Chodas put it in a press statement, “In effect, this small asteroid is caught in a little dance with Earth.”
In another couple of centuries, the asteroid will probably get far enough away that it’ll leave Earth behind forever. I wonder how many times this has happened โ how many times the asteroids have been bigger, closer, but still not big or close enough to stay.
Virtually all climate scientists agree with Dr. Hansen and his co-authors that society is not moving fast enough to reduce emissions of greenhouse gases, posing grave risks. The basic claim of the paper is that by burning fossil fuels at a prodigious pace and pouring heat-trapping gases into the atmosphere, humanity is about to provoke an abrupt climate shift.
Non-linear systems, man. Gradually, then all at once.
In addition to the risk of “several meters” of sea level rise this century, which Hansen calls the most important finding, the final version of Hansen’s paper gives new emphasis to the possibility that the ocean’s heat circulation system may be in the process of shutting down. The circulation shutdown would precede the rapid increase in global sea levels. If the shutdown happens, simultaneous cooling of the waters near Greenland and Antarctica and warming in the tropics and midlatitudes could spawn frequent strong storms on the order of Hurricane Sandy or worse.
The Japanese satellite Himawari caught yesterday’s total solar eclipse as it moved across the Pacific Ocean.
Update:@paulmison sent along some better views of the eclipse: here and here. I tried to find a better YouTube embed, but no dice. This one, taken of the eclipse in Micronesia, is pretty amazing though…you can see the solar flares coming off the surface of the Sun as it reaches totality. Holy shit, I’m getting excited for Eclipsathon 2017!
From NASA, an animation of the yearly cycle of the Earth’s plant life. The data is taken from satellite measurements (plant density for land and chlorophyll concentration for the ocean) and averaged over several years.
From December to February, during the northern hemisphere winter, plant life in the higher latitudes is minimal and receives little sunlight. However, even in the mid latitudes plants are dormant, shown here with browns and yellows on the land and dark blues in the ocean. By contrast the southern ocean and land masses are at the height of the summer season and plant life is revealed with dark green colors on the land and in the ocean. As the year progresses, the situations reverses, with plant life following the increased sunlight northward, while the southern hemisphere experiences decreased plant activity during its winter.
If you’re anything like me, about 2-3 times into the video’s cycle, you’ll be breathing in tune to the Earth. Oxygen in, carbon dioxide out. Carbon dioxide in, oxygen out. Oxygen in, carbon dioxide out… (via @EricHolthaus)
Here’s everything you need to know about the Earth, in a snappy 7-minute video. I am trying very hard not to watch the rest of Kurzgesagt’s videos this afternoon, but I did make time for this one on the Big Bang โ key quote: “time itself becomes wibbly wobbly” โ and how evolution works.
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