There’s some evidence that microbes living inside a rock could be blasted from their home planet, travel through space, and then crash-land on a new planet relatively unscathed. Throughout the ALH84001 debate, scientists assumed fossils could also withstand the grueling journey, but it looks like nobody actually set out to test it—until now.
In a new study, physicists at University of Kent tested the hypothesis with a big gun. More specifically, they took powdered diatoms (a type of microscopic algae with a hard silica shell), packed them inside a nylon bullet, added water, and froze the sample. Then, they loaded the bullets inside a light gas gun and fired them at a sack of water at speeds ranging between 0.25 and 3.1 miles per second.
When they looked in the water afterwards, the researchers analyzed the whole and partial remains of the little diatom fossils. They concluded that small fossils could survive a meteorite impact, and that if they exist, then it’s possible to find them inside meteorites.
But there are a few important caveats. At impact speeds above 0.62 miles per second, none of the diatom fossils survived in one piece—they broke into tiny shards. And the faster they crashed into the water, the tinier the diatom bits became. That’s a problem for any potential fossils that would fall to Earth from other planets, because meteoroids enter the Earth’s atmosphere at speeds between 6.8 and 44.7 miles per second before they hit Earth, according to the American Meteor Society.
The other important limitation is that the diatoms were shot frozen in ice, meaning they potentially behave differently during impact than they would if they were encapsulated in rock.
So the jury is definitely still out on ALH84001, and it probably will be for many years. Even if tests provide stronger evidence that fossils can travel between planetary bodies, it doesn’t necessarily mean they did.
What is pretty neat is that, because meteorite impacts tend to be slower on the Moon, it looks like fossils that have been smashed off from Earth could survive a collision with our natural satellite. The authors conclude that the lunar surface could be a good place to scout for fossils, and those terrestrial transplants may be better preserved on the Moon than if they had remained on Earth.
No word yet on whether a dinosaur fossil could survive the impact. (Dinosaurs on the Moon? That would be crazy awesome.)
Before bows and arrows, language, and even vertical foreheads, some of our ancestors survived by industriously chipping rocks into sharp tools. Today we take metal knives for granted, yet few are made to survive a world without order.
There are two ways to make a knife: Heat up a hunk of metal and hammer it out, or cut out a rough shape and file it to a sharp edge. The latter seemed easier, and I already had some leaf-spring steel from my days as a craftsman of crossbows [see “Rebuild,” April 2014]. But the metal proved too stubborn to cut with a hacksaw.
I needed a forge. The heat would soften the steel and ready it for shaping. I had only a wimpy workshop blowtorch, which can barely melt solder. But if I could trap its heat in one place, the temperature would rise and rise. So I took an empty paint can, punched a hole in the bottom, and screwed in a conduit fitting to hold the blowtorch in place. Firebrick and rock wool (available in most large boiler rooms) insulated my forge extremely well, and in less than 10 minutes, the leaf spring glowed cherry-red.
The softened steel yielded quickly to my hacksaw and files, and I fashioned the knife with a hollow-ground edge for easy sharpening. I also notched out some serrations, which drew blood even before I finished the project.
Now I had a knife-shaped piece of steel, but a durable blade—hard enough to stay sharp and tough so it doesn’t crack—must cool properly. I used prewarmed canola oil to give my blade the right temper.
Did it work? I submitted my knife to the American Bladesmith Society’s punishing test. The blade had to sever a hanging rope with one swipe, chop through a two-by-four, shave off some hair, and bend at a 90-degree angle without breaking in two. To see how it fared, check out the video above.Photograph by Ray Lego
For the July issue of Popular Science, we—the Office for Creative Research—created a data visualization celebrating NASA’s long history of aerospace innovation. Since 1959, NASA has published a document called “Astronautics & Aeronautics Chronology” nearly every year, compiling news coverage of science, technology, and policy at the agency. In these compilations, NASA is reporting its own history. What kinds of stories do these documents hold? How has their language changed over the last six decades? To explore these questions, we created “The Whole Brilliant Enterprise,” a text-based visualization drawn from—by our count—4,861,706 words of NASA history.
The first step was to dig through the NASA chronologies by hand. We discovered that while the reports were an extremely descriptive history of aerospace, they lacked a hierarchy—they were simply straightforward timelines recounting events. A story about the hiring of a new NASA employee might appear alongside a story of a shuttle launch, representing chronological order but not relative importance. That mixed-up quality makes the documents wonderful to skim, but difficult to visualize.
To address the hierarchy issue, we turned to the archives of The New York Times, seeking out NASA-related headlines and articles. We took the articles’ placement in the paper of record—was it front-page news or did the story appear at the back of a section?—as a proxy for cultural impact. Then, we mapped that importance rating back onto the NASA archives, and used it to pull out the text of just the most consequential stories to act as the foundation of the visualization. It was in compiling these results that we realized that the piece should not be a rigid timeline of key NASA events, but instead a rolling impression of the agency’s eras, created by displaying some of the more popular and important terms within the articles.
Once we had the structure in place, the challenge became finding the balance between a term’s chronological location and the type size that would represent its place in the “cultural impact” hierarchy. We also had to space the individual terms evenly along a curved path. It took many iterations of the code that generated the graphic to strike that balance, but eventually we settled on a process that produced an image with the character that we had originally envisioned.
We followed a circuitous path to generate the graphic—the extent of which is evident in our sketches [below]—but we felt it was an appropriate process given the breadth of the archive. The value of our explorations is—like the histories themselves—more striking when viewed in hindsight.A Small Gallery of Our Sketches and In-Progress Images Counting the number of NASA-related New York Times stories We used articles in the New York Times to establish a hierarchy within the stream of stories that NASA compiles in its (almost) annual history reports. Dots here each represent a story, and are arranged by quarter. The most Times stories were published around the July 1969 moon landing. Office for Creative Research A selection of NASA-related New York Times stories, plotted by their length and location in the paper Each dot here represents a NASA-related New York Times story. Page number of the story runs along the x-axis, and the y-axis is the story length in words. Bigger dots are stories that appear in a month that contained lots of other NASA stories—presumably meaning it was among was a flurry of noteworthy events. Lines connect consecutive stories in time. This view allowed us to determine whether our page-ranking algorithm would work to establish a hierarchy of stories in the NASA documents: If the same terms appeared in the NASA stories as in the most important Times stories, those NASA stories are likely more significant. Office for Creative Research A quick visualization of the interconnectedness of select New York Times story abstracts on different NASA topics The white rays around the outside of the ring represent a selection of NASA-related Times stories. Longer stories create longer white radial streaks. When a single term appears in two stories, those stories are connected by an arc. The colors are randomly assigned. Office for Creative Research Identifying the most important terms and beginning to sort them by topic At one point we used a word-cloud approach for our own internal examination of the text. The words are pulled from the NASA reports, and loosely arranged by time on the x-axis. Larger words have a higher importance index, based on our analysis of New York Times articles. They’re colored by category. Office for Creative Research A process shot, as we calculate allowable text heights along the curves of the graphic Before we could fit text along a the curved paths of the graphic, we needed to calculate two parameters: the curvature of the line at each point (so we can lay down text that follows the curves smoothly) and the height between one curve and the next (which tells us how big the text needs to be to fill the space). This image is a screen shot of our algorithm in progress. Office for Creative Research A study of our path-generation algorithm for the flare of “-ing” words running across the background One of the more fanciful elements in the graphic is the streaming white “-ing” words that appear in the background, evoking the flames that propel the spacecraft forward and giving a sense of flow and direction to the piece. This was the output of an early version of our program for generating the paths that we would eventually flow the “-ing” words along. Office for Creative Research Distributing the curves that will corral the text for on each topic in the final graphic The height of the curve is based on the number of stories in the NASA archive in each of the categories we chose to feature. Here, we’re testing how the streams would look for a handful of different category options. Office for Creative Research Finding the perpendicular lines at the curves’ inflection points, for running text along the curves later With the final category streams in place, we then had to assess the shapes of those curves so we could flow the final text along them. Office for Creative Research
Ever since NASA established its history program in 1959, the agency has periodically compiled the world’s aeronautics advances into a single report. Assembled mostly from press releases and news stories, the documents recount coverage of budget negotiations alongside milestones like the shuttle program and the moon landing. Data illustrators at the Office for Creative Research distilled the trove of reports from 11,000 pages and 4.9 million words into just over 4,000 discrete phrases. Their illustration charts the frequency of some of the most important terms, colored by topic and arranged by time, and presents a new view of how NASA took humanity to the stars.
Explore the graphic with your mouse: zoom in and out with the scroll wheel; click and drag to pan; and click on the words that appear in white to see the terms in the original historical reports. Need more pixels? View the piece full-screen. And read more about the illustrators' process in a companion post.
A phrasal history of aerospace. Source: NASA History Program Office; additional data from the New York Times (for relative importance of keywords). Data analysis and visualization by the Office for Creative Research.