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kottke.org posts about science

The Universe is much bigger than it is old

posted by Jason Kottke   Oct 20, 2017

In a Twitter thread, author Oliver Morton compares the physical scale of the Universe with its age (from the perspective of humans).

If a human life is 70 years long, there has been room for 200 million lives since the big bang, but 200 million humans, end to end, would reach just a bit further than the moon. If you had started walking towards the centre of the galaxy on the day of the big bang (had there been days, you, paths & galaxies), you would have got about 20 parsecs by now: just 0.25% of the way.

Maybe walking pace is the wrong metric. A nerve impulse travels around 70 times faster than a person walks. But even at the speed of thought, the age of the universe is too small for something to have reached the centre of the galaxy.

The situation is even worse when you choose another reference object, like UY Scuti, the largest known star. The red hypergiant is nearly 1.5 billion miles across and, because of its size and position near the center of the galaxy, is probably around 13 billion years old, just a few hundred million years younger than the age of the Universe itself.

Even if you use light as a marker, the size of Universe remains unfathomably immense. Over the course of the Universe’s lifetime, a photon could have travelled 13.8 billion light-years, just 15% of the current estimate of the Universe’s diameter of 93 billion light-years. See also what are the physical limits of humanity?

A scientific simulation of Seveneves’ Moon disaster

posted by Jason Kottke   Oct 06, 2017

In the first line of Seveneves, Neal Stephenson lays out the event that the entire book’s action revolves around:

The moon blew up without warning and for no apparent reason.

Mild spoilers, but fairly quickly, scientists in the book figure out that this is a very bad thing that will cause humanity to become extinct unless drastic action is taken.

In the novel, one day the moon breaks up into 7 roughly equal-sized pieces. These pieces continue peacefully orbiting the Earth for a while, and eventually two pieces collide. This collision causes a piece to fragment, making future collisions more likely. The process repeats, at what Stephenson says is an exponential rate, until the Earth is under near-constant bombardment from meteorites, wiping out (nearly) all life on Earth.

Jason Cole wondered how plausible that scenario is and created a simulation to model it. Turns out Stephenson had his figures right.

The Astronomy Photographer of the Year for 2017

posted by Jason Kottke   Oct 04, 2017

Astronomy Photo 2017

Astronomy Photo 2017

Astronomy Photo 2017

Put on by the Royal Observatory Greenwich, The Astronomy Photographer of the Year is the largest competition of its kind in the world. For the 2017 awards, more than 3800 photos were entered from 91 countries. It’s astounding to me that many of these were taken with telescopes you can easily buy online (granted, for thousands of dollars) rather than with the Hubble or some building-sized scope on the top of a mountain in Chile.

The photos above were taken by Andriy Borovkov, Alexandra Hart, and Kamil Nureev.

Researchers may have found a CTE test for living patients

posted by Jason Kottke   Sep 28, 2017

Currently, the only way to diagnose chronic traumatic encephalopathy (CTE), a disease caused by repeated head trauma, is by posthumously examining brain tissue for signs of tau protein buildup. But a group from Boston University may have found a way to test for CTE in living patients.

McKee and her team discovered a specific biomarker in the brains of former football players. A biomarker is a measurable substance which is, in this case, found in the brain and identifies an abnormality.

This particular biomarker is called CCL11, and it’s a secreted protein the human body uses to help regulate the immune system and inflammation in the body.

As The Ringer’s Claire McNear writes, if a CTE test is easily available to players, what will that do to football? (Or indeed, what will it do to sports like soccer, boxing, skateboarding, or even skiing?)

“After learning all of this,” the retiring Ferguson wrote of the clarity he gained when he began researching CTE, “I feel a bit betrayed by the people or committees put in place by the league who did not have my best interests at heart.” He should feel betrayed, as should many of his fellow players. As will, certainly, so very many, once they have the ability to see what has happened to them. They may wonder, rightfully, about the people who trained them and paid them, sometimes even as they attempted to shut down research into CTE. They may look at the league’s structure, at the lopsided contracts that rob many players of their leverage, forcing them to choose between getting back on the field or losing a paycheck (and possibly getting cut), and at how the league cycles through players like they’re nothing more than easily broken pieces on a board.

If you blow air through sand, it behaves like a liquid

posted by Jason Kottke   Sep 21, 2017

If you take a bin full of sand and blow air up through the bottom of it, the sand behaves like a liquid. The bubbles were freaky enough when I watched this for the first time, but when the guy reached in to submerge the ball and it buoyantly popped right to the surface, my brain broke a little bit. This video from The Royal Institution explains what’s going on:

Note that this is a different effect than non-Newtonian liquids (which are also very cool).

Are we living in a simulation?

posted by Jason Kottke   Sep 21, 2017

In the 1990s, futurist and AI researcher Hans Moravec suggested that our Universe might be a simulation.

Assuming the artificial intelligences now have truly overwhelming processing power, they should be able to reconstruct human society in every detail by tracing atomic events backward in time. “It will cost them very little to preserve us this way,” he points out. “They will, in fact, be able to re-create a model of our entire civilization, with everything and everyone in it, down to the atomic level, simulating our atoms with machinery that’s vastly subatomic. Also,” he says with amusement, “they’ll be able to use data compression to remove the redundant stuff that isn’t important.”

But by this logic, our current “reality” could be nothing more than a simulation produced by information entities.

“Of course.” Moravec shrugs and waves his hand as if the idea is too obvious. “In fact, the robots will re-create us any number of times, whereas the original version of our world exists, at most, only once. Therefore, statistically speaking, it’s much more likely we’re living in a vast simulation than in the original version. To me, the whole concept of reality is rather absurd. But while you’re inside the scenario, you can’t help but play by the rules. So we might as well pretend this is real - even though the chance things are as they seem is essentially negligible.”

And so, according to Hans Moravec, the human race is almost certainly extinct, while the world around us is just an advanced version of SimCity.

In 2003, philosopher Nick Bostrom examined the matter more closely:

This paper argues that at least one of the following propositions is true: (1) the human species is very likely to go extinct before reaching a “posthuman” stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation. It follows that the belief that there is a significant chance that we will one day become posthumans who run ancestor-simulations is false, unless we are currently living in a simulation.

In the above (as well as in this follow-up video by Vsauce 3), Kurzgesagt explores these ideas and their implications. Here’s the one that always gets me: If simulations are possible, there are probably a lot of them, which means the chances that we’re inside one of them is high. Like, if there’s one real Universe and 17 quadrillion simulated universes, you’re almost certainly in one of the simulations. <neo>Whoa.</neo>

The physics of sushi

posted by Jason Kottke   Sep 20, 2017

Master sushi chefs in Japan spend years honing their skills in making rice, selecting and slicing fish, and other techniques. Expert chefs even form the sushi pieces in a different way than a novice does, resulting in a cohesive bite that doesn’t feel all mushed together. In this short video clip from a longer Japanology episode on sushi, they put pieces of sushi prepared by a novice and a master through a series of tests — a wind tunnel, a pressure test, and an MRI scan — to see just how different their techniques are. It sounds ridiculous and goofy (and it is!) but the results are actually interesting.

Solar system artwork featuring the precise locations of the planets on the day of your birth

posted by Jason Kottke   Sep 19, 2017

Solar System Birthday Map

Spacetime Coordinates sells prints, metal mementos, and t-shirts that feature the planets of the solar system in the exact locations they were in on the date of your birth (or other significant date). For their new Kickstarter campaign, they’re offering color prints.

While not as pretty as these prints, you can check what the solar system looked like for any date here.

When I was a kid, I spent far too many hours mucking around in Lotus 1-2-3 trying to make a spreadsheet to calculate how often all the planets in the solar system would line up with each other (disregarding their differing planes, particularly Pluto’s).1 I could never get it working. Turns out that a precise alignment has probably never occurred, nor will it ever. But all the planets are “somewhat aligned” every 500 years or so. Neat! (via colossal)

  1. I spent many more hours making a spreadsheet of every single baseball card I owned and how much it was worth, updated by hand from Beckett’s price guide. Time well spent?

What would happen if you brought a tiny piece of the Sun to Earth?

posted by Jason Kottke   Sep 08, 2017

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”.

The intricate wave structure of Saturn’s rings

posted by Jason Kottke   Sep 07, 2017

Saturn Waves by Cassini

On one of its final passes of Saturn, the Cassini probe captured this image of a wave structure in Saturn’s rings known as the Janus 2:1 spiral density wave. The waves are generated by the motion of Janus, one of Saturn’s smaller moons.

This wave is remarkable because Janus, the moon that generates it, is in a strange orbital configuration. Janus and Epimetheus (see “Cruising Past Janus”) share practically the same orbit and trade places every four years. Every time one of those orbit swaps takes place, the ring at this location responds, spawning a new crest in the wave. The distance between any pair of crests corresponds to four years’ worth of the wave propagating downstream from the resonance, which means the wave seen here encodes many decades’ worth of the orbital history of Janus and Epimetheus. According to this interpretation, the part of the wave at the very upper-left of this image corresponds to the positions of Janus and Epimetheus around the time of the Voyager flybys in 1980 and 1981, which is the time at which Janus and Epimetheus were first proven to be two distinct objects (they were first observed in 1966).

The photograph is also an optical illusion of sorts. The rings appear to be getting farther away in the upper lefthand corner but the plane of the photograph is actually parallel to the plane of the rings…it’s just that the wavelength of the density wave gets shorter from right to left.

Update: Here are those density waves converted into sound waves. The first set sounds like an accelerating F1 car.

Newly processed photos of Jupiter taken by NASA’s Juno probe

posted by Jason Kottke   Aug 31, 2017

Jupiter Juno

Jupiter Juno

Jupiter Juno

Seán Doran shared some recently processed photos of Jupiter that he worked on with Gerald Eichstädt. The photos were taken by NASA’s Juno probe on a recent pass by the planet. These are like Impressionist paintings…you could spend hours staring at the whirls & whorls and never find your way out. There are more images of Jupiter in Doran’s Flickr album, including this high-resolution shot that you can download for printing.

Black holes could delete the Universe

posted by Jason Kottke   Aug 25, 2017

In their latest video, Kurzgesagt takes a look at black holes, specifically how they deal with information. According to the currently accepted theories, one of the fundamental laws of the Universe is that information can never be lost, but black holes destroy information. This is the information paradox…so one or both of our theories must be wrong.

The paradox arose after Hawking showed, in 1974-1975, that black holes surrounded by quantum fields actually will radiate particles (“Hawking radiation”) and shrink in size (Figure 4), eventually evaporating completely. Compare with Figure 2, where the information about the two shells gets stuck inside the black hole. In Figure 4, the black hole is gone. Where did the information go? If it disappeared along with the black hole, that violates quantum theory.

Maybe the information came back out with the Hawking radiation? The problem is that the information in the black hole can’t get out. So the only way it can be in the Hawking radiation (naively) is if what is inside is copied. Having two copies of the information, one inside, one outside, also violates quantum theory.

So maybe black holes holographically encode their information on the surface?

Great 1970 eclipse stamp by the legendary Lance Wyman

posted by Jason Kottke   Aug 24, 2017

Lance Wyman Eclipse Stamp

A Mexican postage stamp designed in honor of the 1970 total solar eclipse. It was designed by Lance Wyman, who also did the logo and graphics for the 1968 Olympics in Mexico City.

The best photos and videos of the 2017 solar eclipse

posted by Jason Kottke   Aug 23, 2017

2017 Eclipse Photos

2017 Eclipse Photos

2017 Eclipse Photos

2017 Eclipse Photos

2017 Eclipse Photos

2017 Eclipse Photos

2017 Eclipse Photos

Photo and video credits from the top: Nashville progression photo by Richard Sparkman. HDR photo with Moon detail by Dennis Sprinkle (this one blew my mind a little). Rock climber by Ted Hesser (the story behind the photo). Progression photo by Jasman Lion Mander. Photo from the Alaska Airlines flight by Tanya Harrison. Video of the eclipse shadow moving across the Earth from the NOAA’s DSCOVR satellite. Neon cowboy photo by Rick Armstrong. ISS transit photo and video by Joel Kowsky. Partial eclipse video by NASA’s SDO spacecraft. Partial eclipse video by the ESA’s Proba-2 satellite. Video of the eclipse shadow moving across the US by the NOAA’s GOES-16 weather satellite. Time lapse video from The Salt Lake Tribune. Amazing 4K close-up video by JunHo Oh, ByoungJun Jeong, and YoungSam Choi…check out those prominences!

More eclipse photos on Petapixel (and here), BBC, Bored Panda, The Verge, and the NY Times.

Update: I added the time lapse video from The Salt Lake Tribune. (via the kid should see this)

Update: Added the 4K close-up video.

What witnessing a total eclipse is like

posted by Jason Kottke   Aug 23, 2017

In an essay from 1982 about her seeing a total solar eclipse in Washington (recently republished in this collection), Pulitzer Prize winner Annie Dillard puts into words what I only attempted to express in my eclipse experience.

I had seen a partial eclipse in 1970. A partial eclipse is very interesting. It bears almost no relation to a total eclipse. Seeing a partial eclipse bears the same relation to seeing a total eclipse as kissing a man does to marrying him, or as flying in an airplane does to falling out of an airplane. Although the one experience precedes the other, it in no way prepares you for it.

I heard lots of disappointment with the eclipse among friends and on social media. It was neat — look, there’s a chunk out of the Sun — but they thought it would be darker or that the air would get colder. But none of that stuff really happens unless you’re really close to totality…and then it goes completely dark and your brain turns inside out. Twitter user @hwoodscotty said:

Probably the coolest thing I’ve ever seen. Totality is so much different than even 99%. 10/10 Would recommend.

And @omanreagan:

Standing on a mountaintop for totality was crossing into another dimension, suddenly finding ourselves on another world. Amazing. Sparkling ring, sun fire ghostly streaming, darkest circle. I understand now why people chase the eclipse. Totality is unlike anything. Entire landscape shifted, valleys, hills, mountains painted in nightcolour and cold. Sparkling planets came out in a midnight sky.

But back to Dillard’s piece…this part, about the shadow rushing towards them, sounds amazing:

I have said that I heard screams. (I have since read that screaming, with hysteria, is a common reaction even to expected total eclipses.) People on all the hillsides, including, I think, myself, screamed when the black body of the moon detached from the sky and rolled over the sun. But something else was happening at that same instant, and it was this, I believe, which made us scream.

The second before the sun went out we saw a wall of dark shadow come speeding at us. We no sooner saw it than it was upon us, like thunder. It roared up the valley. It slammed our hill and knocked us out. It was the monstrous swift shadow cone of the moon. I have since read that this wave of shadow moves 1,800 miles an hour. Language can give no sense of this sort of speed — 1,800 miles an hour. It was 195 miles wide. No end was in sight — you saw only the edge. It rolled at you across the land at 1,800 miles an hour, hauling darkness like plague behind it. Seeing it, and knowing it was coming straight for you, was like feeling a slug of anesthetic shoot up your arm. If you think very fast, you may have time to think, “Soon it will hit my brain.” You can feel the deadness race up your arm; you can feel the appalling, inhuman speed of your own blood. We saw the wall of shadow coming, and screamed before it hit.

Next time, and there will definitely be a next time, I’m hoping to get up high somewhere so I can see the shadow and more of the 360-degree sunset. BRB, pricing plane tickets to Argentina

Update: Before the 2017 eclipse, Vox talked to some eclipse chasers about what it’s like to witness a total solar eclipse.

Joss Fong, who produced the video, shared the following on Twitter:

now that i’ve recovered from the drive, i can say that a lot of what these eclipse chasers told me makes sense now. agree completely that it’s something you have to see for yourself. what was different for me though is …. i got pretty sad. there’s a fine line between awe and grief. maybe in a different year it would have gone the other way, but tbh every exceptionally beautiful sunset makes me a tiny bit sad too. but this was sunset sadness times a thousand. absolutely punched by the impermanence. i hope i see it again and i hope you can see it too.

Update: From XKCD:

XKCD eclipse

I watched from a beautiful nature reserve in central Missouri, and it was — without exaggeration — the coolest thing I’ve ever seen.

My 2017 total solar eclipse trip

posted by Jason Kottke   Aug 22, 2017

Eclipse 2017 Mouser

I was not prepared for how incredible the total eclipse was. It was, literally, awesome. Almost a spiritual experience. I also did not anticipate the crazy-ass, reverse storm-chasing car ride we’d need to undertake in order to see it.

I’m not a bucket list sort of person, but ever since seeing a partial eclipse back in college in the 90s (probably this one), I have wanted to witness a total solar eclipse with my own eyes. I started planning for the 2017 event three years ago…the original idea was to go to Oregon, but then some college friends suggested meeting up in Nebraska, which seemed ideal: perhaps less traffic than Oregon, better weather, and more ways to drive in case of poor weather.

Well, two of those things were true. Waking up on Monday, the cloud cover report for Lincoln didn’t look so promising. Rejecting the promise of slightly better skies to the west along I-80, we opted instead to head southeast towards St. Joseph, Missouri where the cloud cover report looked much better. Along the way, thunderstorms started popping up right where we were headed. Committed to our route and trusting this rando internet weather report with religious conviction, we pressed on. We drove through three rainstorms, our car hydroplaning because it was raining so hard, flood warnings popping up on our phones for tiny towns we were about to drive through. Morale was low and the car was pretty quiet for awhile; I Stoically resigned myself to missing the eclipse.

But on the radar, hope. The storms were headed off to the northeast and it appeared as though we might make it past them in time. The Sun appeared briefly through the clouds and from the passenger seat, I stabbed at it shining through the windshield, “There it is! There’s the Sun!” We angled back to the west slightly and, after 3.5 hours in the car, we pulled off the road near the aptly named town of Rayville with 40 minutes until totality, mostly clear skies above us. After our effort, all that was missing was a majestic choral “ahhhhhh” sound as the storm clouds parted to reveal the Sun.

My friend Mouser got his camera set up — he’d brought along the 500mm telephoto lens he uses for birding — and we spent some time looking at the partial eclipse through our glasses, binoculars (outfitted with my homemade solar filter), and phone cameras. I hadn’t seen a partial eclipse since that one back in the 90s, and it was cool seeing the Sun appear as a crescent in the sky. I took this photo through the clouds:

Eclipse 2017 Clouds

Some more substantial clouds were approaching but not quickly enough to ruin the eclipse. I pumped my fist, incredulous and thrilled that our effort was going to pay off. As totality approached, the sky got darker, our shadows sharpened, insects started making noise, and disoriented birds quieted. The air cooled and it even started to get a little foggy because of the rapid temperature change.

We saw the Baily’s beads and the diamond ring effect. And then…sorry, words are insufficient here. When the Moon finally slipped completely in front of the Sun and the sky went dark, I don’t even know how to describe it. The world stopped and time with it. During totality, Mouser took the photo at the top of the page. I’d seen photos like that before but had assumed that the beautifully wispy corona had been enhanced with filters in Photoshop. But no…that is actually what it looks like in the sky when viewing it with the naked eye (albeit smaller). Hands down, it was the most incredible natural event I’ve ever seen.

After two minutes — or was it several hours? — it was over and we struggled to talk to each other about what we had just seen. We stumbled around, dazed. I felt high, euphoric. Raza Syed put it perfectly:

It was beautiful and dramatic and overwhelming — the most thrillingly disorienting passage of time I’ve experienced since that one time I skydived. It was a complete circadian mindfuck.

After waiting for more than 20 years, I’m so glad I finally got to witness a total solar eclipse in person. What a thing. What a wondrous thing.

Update: Here are some reports from my eclipse-chasing buddies: a photo of Mouser setting up his camera rig, Nina’s sharp shadow at 99% totality, and Mouser’s slightly out-of-focus shot of the Sun at totality (with an account of our travels that day).

Solar eclipse myth busted: it’s perfectly safe for kids to be outside during an eclipse

posted by Jason Kottke   Aug 20, 2017

Throughout history, total solar eclipses have been unnerving. To ancient cultures, they signified bad omens, the apocalypse, or that the Sun was being eaten by a sky creature.

There were a tumult, and disorder. All were disquieted, unnerved, frightened. Then there was weeping. The commonfolk raised a cup, lifting their voices, making a great din, calling out shrieking. People of light complexion were slain as sacrifices; captives were killed. All offered their blood.

But even in modern times, a lack of scientific understanding of what happens during a solar eclipse can cause apprehension and panic. Until hearing the same story from two different people in the past week, I had no idea that during solar eclipses, it is routine for schoolchildren to be kept inside until the “danger” has passed. Charles Fulco, a NASA and AAS 2017 U.S. Eclipse Educator, is trying to allay these fears by addressing common eclipse misconceptions.

“The Sun is more dangerous during an eclipse.” This is utter nonsense and for some reason, has persisted into the 21st Century. An eclipsed Sun is no more dangerous than the “everyday” Sun, but for some reason, some districts still keep teachers and students in their rooms with pulled shades, watching the eclipse on a screen, rather than outdoors, safely and under the care of a professional educator. I believe their fear of nature is transferred to the students as well: If the adult says an eclipse is scary and dangerous, than it must be!

Phil Plait agrees:

As I make my final preparations for my eclipse travels (rural western Wyoming, if you’re curious) I’m hearing stories that are making me very unhappy: Some school districts across the country are telling children to stay inside during the eclipse, out of fear they’ll damage their eyes.

Let me be clear: Schools, administrators, teachers, parents: Don’t do this. YOU CAN LET THE KIDS SEE THE ECLIPSE. You just have to be safe about it.

I can appreciate the difficulty of telling 25 first graders there’s something cool happening with the Sun and then trying to get them not to look directly at it, but keeping kids inside is not the answer. For one thing, they’re missing out on a genuine celestial spectacle & learning opportunity and for another, you’re teaching people bad science. A friend, who is one of the smartest people I know, was genuinely concerned for her kids’ safety during the eclipse because when she was a kid, she was kept inside a classroom with the shades drawn because, she was told, it was dangerous for them to be outside. Dangerous to be outside in the sunshine! A clear case of educators doing the exact opposite of what they should be doing.

A simulated “play-by-play” of a total eclipse

posted by Jason Kottke   Aug 20, 2017

This video from the Weather Channel is pretty neat and useful: a play-by-play of what to expect during the eclipse, from being able to see Venus in broad daylight to animals possibly acting weird to the 360-degree “sunset” that happens about 2 minutes before totality.

How to predict total solar eclipses

posted by Jason Kottke   Aug 18, 2017

The Exploratorium in San Francisco has produced a great explainer video about the science of predicting total solar eclipses. Each eclipse belongs to a repeating series of eclipses called a Saros cycle that repeats every 18 years 11 days and 8 hours.

Saros 145

There are now 40 active Saros cycles and the August 2017 eclipse belongs to Saros 145, which produced its first total eclipse in June 1909 and will produce its last total eclipse in September 2648.

Infographic of the fascinating timeline of the far future

posted by Jason Kottke   Aug 17, 2017

Timeline of The Far Future

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.”

A tour of our solar system’s eclipses

posted by Jason Kottke   Aug 16, 2017

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)

Scientists think the first Americans arrived by boat

posted by Jason Kottke   Aug 15, 2017

The prevailing theory of how the Americas were settled has been than human hunters followed big game across the ice-free land bridge between North America and Asia around 13,000 years ago. These are the Clovis people you may have learned about in school. But evidence is mounting that the first humans to settle the Americas came down the Pacific Coast somewhat earlier than that.

The Cedros Island sites add to a small but growing list that supports a once-heretical view of the peopling of the Americas. Whereas archaeologists once thought that the earliest arrivals wandered into the continent through a gap in the ice age glaciers covering Canada, most researchers today think the first inhabitants came by sea. In this view, maritime explorers voyaged by boat out of Beringia — the ancient land now partially submerged under the waters of the Bering Strait — about 16,000 years ago and quickly moved down the Pacific coast, reaching Chile by at least 14,500 years ago.

Part of the problem in confirming this hypothesis is that the rise in sea level that accompanied the melting of the glaciers (a 120-meter rise globally) submerged likely settlement sites, trapping archeological evidence under hundreds of feet of ocean. (via @CharlesCMann)

The size of life: the differing scales of living things

posted by Jason Kottke   Aug 10, 2017

In the first in a series of videos, Kurzgesagt tackles one of my favorite scientific subjects: how the sizes of animals governs their behaviors, appearance, and abilities. For instance, because the volume (and therefore mass) of an organism increases according to the cube of the increase in length (e.g. if you double the length/height of a dog, its mass roughly increases by 8 times), when you drop differently sized animals from high up, the outcomes are vastly different (a mouse lands safely, an elephant splatters everywhere).

The bit in the video about how insects can breathe underwater because of the interplay between the surface tension of water and their water-repellant outer layers is fascinating. The effect of scale also comes into play when considering the longevity of NBA big men, how fast animals move, how much animals’ hearts beat, the question of fighting 100 duck-sized horses or 1 horse-sized duck, and shrinking people down to conserve resources.

When humans get smaller, the world and its resources get bigger. We’d live in smaller houses, drive smaller cars that use less gas, eat less food, etc. It wouldn’t even take much to realize gains from a Honey, I Shrunk Humanity scheme: because of scaling laws, a height/weight proportional human maxing out at 3 feet tall would not use half the resources of a 6-foot human but would use somewhere between 1/4 and 1/8 of the resources, depending on whether the resource varied with volume or surface area. Six-inch-tall humans would potentially use 1728 times fewer resources.

See also The Biology of B-Movie Monsters, which is perhaps the most-linked article in the history of kottke.org.

Voronoi diagram of people enjoying a park

posted by Jason Kottke   Aug 03, 2017

Voronoi Bryant Park

Starting with an overhead shot of people sitting out in the sun in NYC’s Bryant Park, Rod Bogart laid what’s called a Voronoi diagram on top of it. A Voronoi diagram is a way of mapping out areas where any point in a given area is closer to a seed point than it is to any other seed point. You can think of it as a sphere of influence…and in this case, you can see how the park-goers have organized themselves into having their own personal space. As Bogart says:

It’s fascinating to see the real world optimization problem of wanting to get a nice large patch of grass.

I often think about Voronoi diagrams when I get into an elevator.

I stand alone in the elevator, right in the middle, equidistant from the four walls. Before the doors close, a woman enters. Unconsciously, I move over to make room for her. We stand side by side with equal amounts of space between the two of us and between each of us and the walls of the elevator. On the 12th floor, a man gets on and the woman and I slide slightly to the side and to the back, maximizing the space that each of us occupies in the elevator. At the 14th floor, another man gets on. The man in front steps to the back center and the woman and I move slightly toward the front, forming a diamond shape that again maximizes each person’s distance from the elevator walls and the people next to them.

See also “the human ellipse”.

Browse the British Library’s online copy of Leonardo da Vinci’s 570-page notebook

posted by Jason Kottke   Aug 02, 2017

Leonardo's Notebook

Leonardo's Notebook

Leonardo's Notebook

Leonardo da Vinci was an avid taker of notes. Over the course of his working life, he filled thousands of pages with drawings, sketches, equations, and his distinctive mirrored handwriting. The British Library has one of Leonardo’s notebooks and has digitized and put all 570 pages of it online. It’s interesting to see all of the spare geometric line drawings and then every once in awhile there’s this wonderfully rendered 3D-shaded tiny masterpiece in the margin when more detail was required. (via open culture)

A visual explanation of quantum mechanics

posted by Jason Kottke   Jul 27, 2017

From the ViaScience YouTube channel comes this 31-part video explainer of quantum mechanics. As the introduction video notes, there is a fair bit of math in these videos presented at a quick pace, but if you took calculus in high school or college and remember the notation, that (and the pause button) should get you through this pretty well. (via @jsonpaul, who calls the series “fantastic”)

Why is the upcoming total solar eclipse such a big deal?

posted by Jason Kottke   Jul 20, 2017

Well, the short answer is that they don’t happen all that often and when they do, they’ve visible from only a small bit of Earth. Joss Fong elaborates in a video for Vox.

The next total solar eclipse to visit the US will be in 2024. If an eclipse happens to come to your town, you’re lucky. Any given location will see a total solar eclipse only once in more than 300 years, on average. The vast majority of us will have to travel to an eclipse path if we want to see a total eclipse in our lifetimes.

I’m off to Nebraska in August to meet up with some friends and see the eclipse. (And that 2024 eclipse Fong mentions? The path of totality goes right over my damn house. Woooo!) But no matter where you are in North America, you can enjoy the eclipse…just make sure you buy some safety glasses (and other supplies) if you want to look directly at the Sun. (via @veganstraightedge)

Beating cancer is a team sport

posted by Jason Kottke   Jul 20, 2017

Senator John McCain has been diagnosed with a particularly aggressive form of brain cancer. The tumor has been removed and McCain is recovering at home with his family. I wish Senator McCain well and hope for a speedy recovery.

In the wake of his diagnosis, many of those expressing support for McCain reference his considerable personal strength in his fight against cancer. President Obama said:

John McCain is an American hero & one of the bravest fighters I’ve ever known. Cancer doesn’t know what it’s up against. Give it hell, John.

McCain’s daughter Meghan references his toughness and fearlessness in a statement released yesterday. Vice-President Joe Biden expressed similar sentiments on Twitter:

John and I have been friends for 40 years. He’s gotten through so much difficulty with so much grace. He is strong — and he will beat this.

This is the right thing to say to those going through something like this, and hearing this encouragement and having the will & energy to meet this challenge will undoubtably increase McCain’s chances of survival. But what Biden said next is perhaps more relevant:

Incredible progress in cancer research and treatment in just the last year offers new promise and new hope. You can win this fight, John.

As with polio, smallpox, measles, and countless other diseases before it, beating cancer is not something an individual can do. Being afflicted with cancer is the individual’s burden to bear but society’s responsibility to cure. In his excellent biography of cancer from 2011, The Emperor of All Maladies, Siddhartha Mukherjee talks about the progress we’ve made on cancer:

Incremental advances can add up to transformative changes. In 2005, an avalanche of papers cascading through the scientific literature converged on a remarkably consistent message — the national physiognomy of cancer had subtly but fundamentally changed. The mortality for nearly every major form of cancer — lung, breast, colon, and prostate — had continuously dropped for fifteen straight years. There had been no single, drastic turn but rather a steady and powerful attrition: mortality had declined by about 1 percent every year. The rate might sound modest, but its cumulative effect was remarkable: between 1990 and 2005, the cancer-specific death rate had dropped nearly 15 percent, a decline unprecedented in the history of the disease. The empire of cancer was still indubitably vast — more than half a million American men and women died of cancer in 2005 — but it was losing power, fraying at its borders.

What precipitated this steady decline? There was no single answer but rather a multitude. For lung cancer, the driver of decline was primarily prevention — a slow attrition in smoking sparked off by the Doll-Hill and Wynder-Graham studies, fueled by the surgeon general’s report, and brought to its full boil by a combination of political activism (the FTC action on warning labels), inventive litigation (the Banzhaf and Cipollone cases), medical advocacy, and countermarketing (the antitobacco advertisements). For colon and cervical cancer, the declines were almost certainly due to the successes of secondary prevention — cancer screening. Colon cancers were detected at earlier and earlier stages in their evolution, often in the premalignant state, and treated with relatively minor surgeries. Cervical cancer screening using Papanicolaou’s smearing technique was being offered at primary-care centers throughout the nation, and as with colon cancer, premalignant lesions were excised using relatively minor surgeries. For leukemia, lymphoma, and testicular cancer, in contrast, the declining numbers reflected the successes of chemotherapeutic treatment. In childhood ALL, cure rates of 80 percent were routinely being achieved. Hodgkin’s disease was similarly curable, and so, too, were some large-cell aggressive lymphomas. Indeed, for Hodgkin’s disease, testicular cancer, and childhood leukemias, the burning question was not how much chemotherapy was curative, but how little: trials were addressing whether milder and less toxic doses of drugs, scaled back from the original protocols, could achieve equivalent cure rates.

Perhaps most symbolically, the decline in breast cancer mortality epitomized the cumulative and collaborative nature of these victories — and the importance of attacking cancer using multiple independent prongs. Between 1990 and 2005, breast cancer mortality had dwindled an unprecedented 24 percent. Three interventions had potentially driven down the breast cancer death rate-mammography (screening to catch early breast cancer and thereby prevent invasive breast cancer), surgery, and adjuvant chemotherapy (chemotherapy after surgery to remove remnant cancer cells).

Understanding how to defeat cancer is an instance where America’s fierce insistence on individualism does us a disservice. Individuals with freedom to pursue their own goals are capable of a great deal, but some problems require massive collective coordination and effort. Beating cancer is a team sport; it can only be defeated by a diverse collection of people and institutions working hard toward the same goal. It will take government-funded research, privately funded research, a strong educational system, philanthropy, and government agencies from around the world working together. This effort also requires a system of healthcare that’s available to everybody, not just to those who can afford it. Although cancer is not a contagious disease like measles or smallpox, the diagnosis and treatment of each and every case brings us closer to understanding how to defeat it. We make this effort together, we spend this time, energy, and money, so that 10, 20, or 30 years from now, our children and grandchildren won’t have to suffer like our friends and family do now.

An appreciation and reevaluation of Contact, 20 years after its theatrical release

posted by Jason Kottke   Jul 12, 2017

Contact, based on Carl Sagan’s book of the same name, is on its face a movie about science vs. religion. On the 20th anniversary of its release, Germain Lussier rewatched the film and came away with a different impression: director Robert Zemeckis wanted viewers to think about our relationship to media and technology.

Once Ellie and her team discover the signal from Vega, seemingly every scene in the film features a monitor or some kind of television-related paraphernalia. Whether that’s unpacking a TV to unveil the Olympic footage, people watching news reports on CNN, a terrorist videotaping himself, or multiple scenes in the screen-filled Mission Control, Contact is filled with monitors, forcing both the characters and the audience to watch them. Full scenes of the film are made up of fuzzy TV footage. There are numerous press conferences on TV. The selection of the Machine representative unfolds via the news. Ellie’s interactions with Hadden are almost entirely done over a monitor. Even in scenes where the camera is in a room with the characters, Zemeckis often films them watching TV, or simply puts TV monitors in the frame to constantly remind us they’re there.

But that’s not it. People video chat regularly, which was not common in 1997. The terrorist attack on the Machine is first discovered on a TV monitor and subsequently played out there too. Then, finally, what’s the smoking gun of Ellie’s whole trip at the end of the movie? Eighteen hours of video footage. I could go on and on with examples where Contact uses television and monitors, but once you start seeing the film’s obsession with video, it’s almost comical how often it’s used. Which poses the obvious question, “Why?”

In this light, the organized religion & organized science depicted in the film are just other forms of mediated experience, separate from the personal experience of seeing something with your own eyes.

Contact is one of my favorite movies — I watch it every 12-18 months or so — and this makes me appreciate it all the more. And I had forgotten how good the trailer was:

It’s dead simple: that amazingly resonant Vega signal sound over a series of quickly cut scenes that tells the story in miniature. Surely this belongs on best movie trailers lists as much as any of these.

Oh, and while I’m not generally a fan of reboots, I would love to see what Denis Villeneuve could do with Sagan’s story. I’m also not crazy about Jodie Foster — I find her less and less tolerable as Arroway with each viewing — so it would be cool to see another actress in the role. Arrival’s Amy Adams is almost too on the nose…how about Lupita Nyong’o, ?Emma Watson, Janelle Monáe, Brie Larson, or Emma Stone?

How to safely enjoy the 2017 solar eclipse, a buyer’s guide for normal people

posted by Jason Kottke   Jul 12, 2017

Solar Eclipse Illo

Important update: Since I published this guide a month ago, NASA and the AAS have updated their recommendation on buying solar safety glasses due to reports of counterfeit eclipse glasses. They no longer recommend looking for the ISO rating alone but only buying from a recommended manufacturer. If you have purchased glasses or are going to purchase glasses, read this page carefully before using them, paying particular attention to this bit:

Unfortunately, you can’t check whether a filter meets the ISO standard yourself — doing so requires a specialized and expensive piece of laboratory equipment called a spectrophotometer that shines intense UV, visible, and IR light through the filter and measures how much gets through at each wavelength. Solar filter manufacturers send their products to specialized labs that are accredited to perform the tests necessary to verify compliance with the ISO 12312-2 safety specifications. Once they have the paperwork that documents their products as ISO-compliant, they can legitimately use the ISO logo on their products and packaging.

Even more unfortunately, unscrupulous vendors can grab the ISO logo off the internet and put it on their products and packaging even if their eclipse glasses or viewers haven’t been properly tested. This means that just seeing the ISO logo or a label claiming ISO 12312-2 certification isn’t good enough. You need to know that the product comes from a reputable manufacturer or one of their authorized dealers.

Amazon recently sent out emails to the buyers of the plastic-framed glasses I bought and linked to here (“habibee 4-Pack Black Plastic Eclipse Glasses CE & ISO Certified 2017 Safe Solar Eclipses Viewing Shades Block Sun Ultraviolet UV Lights Goggles”), saying that they have “not received confirmation from the supplier of your order that they sourced the item from a recommended manufacturer” and, to their credit, have automatically issued refunds to those buyers. They also appear to have removed any products from their site that aren’t sourced from a recommended manufacturer. This doesn’t necessarily mean the glasses are faulty…it just means the solar filter paper used for the lenses can’t be sourced. Again, read this page carefully before deciding to use any glasses you may have purchased. I tested a pair this morning, looking at bright light bulbs and they seem appropriately dark, but as noted by the AAS, who knows about the UV and IR filtering? I’m throwing mine out.

The cardboard-framed glasses I linked to (while currently sold out) are manufactured by American Paper Optics, which is on the AAS’s list of reputable vendors. Also on the list is the manufacturer of the solar filter sheets, Thousand Oaks Optical. The two cardboard camera lens covers I linked to have been deleted from Amazon, a sign that their sourcing cannot be verified. I’ve updated the links and text below to only include links to products on the list of reputable vendors. Most are sold out at this point anyway, so…

I wish I’d had these new NASA and AAS recommendations a month ago…I obviously would have followed them closely in making buying choices & recommendations. That some unscrupulous manufacturers are using people’s enthusiasm for science and viewing the eclipse to sell potentially harmful products makes me angry and sick to my stomach. Luckily Amazon is doing the right thing here with refunds and safety notices. And thanks to NASA and the AAS for their guidance…again please read this before using your eclipse glasses, even ones you may have gotten free from your public library or through other organizations. /end update

On August 21, 2017 across the entire United States, the Moon will move in front of the Sun, partially blocking it from our view. For those on the path of totality, the Moon will entirely block out the Sun for more than 2 minutes. I’ve been looking forward to seeing a total solar eclipse since I was a little kid, so I’ve been doing a lot of research on what to buy to enjoy the eclipse safely. Here’s what I’ve come up with.

I’ve oriented this guide toward the enthusiastic beginner, someone who’s excited about experiencing the wonder of the eclipse with their friends & family but isn’t interested in expensive specialty gear or photography (like me!). And, again, since you will be able to see this eclipse from everywhere in North America to some degree, this guide applies to anyone in the US/Canada/Mexico.

In planning for eclipse viewing, please check out NASA’s safety notes for more information. Make sure that whatever you buy, it’s properly rated for naked eye solar viewing. Looking directly at the Sun without a proper filter can cause permanent damage, particularly through binoculars, a camera lens, or a telescope.

Note: If you’re going to get eclipse supplies, now is the time. Some of this stuff will probably be very difficult to find (or very expensive) as we approach August 21 — for instance, shipping estimates on Amazon for some of the glasses are mid-August already.

Solar eclipse glasses are essential. Right up until the Sun goes completely behind the Moon (if you’re on the path of totality), you will want to look at the crescent-shaped Sun and you’ll need certified safety glasses to do so. Regular sunglasses will not work! Do not even. There are several options…find some in stock that ship soon. Note: If you have young kids, splurge for the plastic framed glasses (if you can find them…most are sold out now)…my testing indicates the cardboard ones don’t stay on smaller heads as well.

Make a pinhole viewer. A pinhole viewer will let you see the shape of the eclipsed Sun without having to look directly at it. This Exploratorium guide should get you started. All you need in terms of supplies you probably have lying around at home: aluminum foil, paper, cardboard, etc. I suspect Kelli Anderson’s This Book is a Camera ($27) might also work if you play with the exposure times?

Apply good sunscreen. You’ve got your eye protection down, now for the rest of yourself. The eclipse is happening in the middle of the day in much of the country, in what you hope will be complete sunshine, so bring some sunscreen. The Sweethome recommends this SPF 70 Coppertone for $9. Wear a cap. Stay in the shade. Bonus for shading yourself under trees: the gaps between the leaves will form little pinhole lenses and you’ll see really cool patterns:

Solar Eclipse Leaves

A nice pair of binoculars. If you’re in the path of totality, you might want a pair of binoculars to look more closely at the totally eclipsed Sun (after checking that it’s safe!!). I’m guessing you don’t want to buy a pair of specialty astronomy binoculars, so the best binoculars are probably ones you already own. If you don’t already have a pair, The Wirecutter recommends the Midas 8 x 42 binoculars by Athlon Optics ($290) with the Carson VP 8x42mm ($144) as a budget pick. (For solar filter options, see below.)

A solar filter for your camera. If you have a camera, they might make a solar filter for whatever lens you want to use. Hydrogen alpha filters will allow you to see the most detail — “crazy prominences and what-not” in the words of a photography pal of mine — but are also pretty expensive. You can buy solar filter sheets ($29) to make your own lens coverings for your camera, binoculars, or telescope. Quality will likely not be fantastic, but you’ll get something. Safety warning: place any filters in front of lenses or it can burn a hole in the filter (and then into your eye); i.e. don’t use binoculars in front of safety glasses!!

Note for budding solar photographers: Shooting the eclipse will be challenging. First there’s too much light and you’ll need a filter. Then when totality occurs, you’ll be in the dark needing a tripod and a fast lens. Plan accordingly…or leave it all at home and look at the thousands of photos taken by pro photographers after the fact.

Ok, that’s it. Have a good eclipse and stay safe!

Update: I removed a reference to the plastic-rimmed safety glasses I ordered because the image has changed on this item since I ordered them and published this guide…it’s now a wire-rimmed pair of glasses. I would recommend getting something else instead, just to be safe. (thx, @kahnnn)

Update: NASA has been alerted that some of the paper glasses being sold are not safe for viewing the eclipse. When buying, look for the ISO icon (referencing 12312-2) and for glasses made by these recommended manufacturers: American Paper Optics, Rainbow Symphony, Thousand Oaks Optical, or TSE 17. (via @ebellm)

Update: The Wirecutter has released their guide to The Best Solar Eclipse Glasses and Filters and they recommend the Celestron EclipSmart 2x Power Viewers (2-pack for $10), which provide not only certified eye protection but a nice 2X zoom.