JULY 29, 2015
The Other Side of the "Blue Marble"
Last week NASA released an updated image of fully illuminated Earth. Here is the other side, with Africa front and center.
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—“It’s your home. Imagine you start eating and you see the wine in your glass going left to right.”
Silvian Marcus, a director of building structures for WSP, on technology used to keep skinny skyscrapers from swaying.
AUGUST 7, 2015
Stung by a Venomous Frog, and Happy About It
This week archaeologists, wildlife ecologists and other scientists on Twitter shared embarrassing moments from their field research using the hashtag#FieldWorkFail. Among the confessions were tales of elephants crushing trap cameras, paleontologists accidentally swallowing fossils, and one case where a researcher unintentionally glued herself to a crocodile.
Not all fieldwork mistakes are as amusing, but even the unfunny ones can be fortuitous. For Carlos Jared, a biologist from the Butantan Institute in São Paulo, Brazil, a mishap in the desert led to a new discovery.
Dr. Jared had been studying tree frogs in the cactus and thorn forests of northeastern Brazil for decades. But on one particular day he wanted to get his hands on Corythomantis greeningi, a frog with a helmet-shaped head covered in tiny spines.
“During collection, very soon I realized that when grasping them with the palm of the hand, they intensely move the head in a characteristic butting behavior,” Dr. Jared said in an email. Later he felt a sharp pain radiating through his arm, which he described as being far worse than the worst wasp sting imaginable. Dr. Jared was at least four hours away from any hospital, so he decided to tough it out in the desert. Five hours later, the excruciating pain subsided on its own.
It wasn’t until he examined the frogs under a microscope that he discovered that the spines on their upper lips were covered in poison glands. “It took me a long time to realize that the pain had a relationship with the intense and careless collection of these animals hitting the palm of my hands,” he said. When the frog head-butted him, it envenomed him too.
Researchers already knew that the frog secretes toxins from its skin, but the poisoned spines on the head had not been documented before. Dr. Jared and his colleagues found that the same spiny and bony head occurs in another frog species, Aparasphenodon brunoi, which lives in the Atlantic rain forests of South America. They decided to test how toxic the two frogs were in the lab by injecting the poisons into rodents. To their surprise, they found that in mice, A. brunoi's secretions were 25 times as lethal as a Brazilian pit viper's venom, and those of C. greeningi, the one that pricked Dr. Jared, were twice as lethal.
Although Dr. Jared did not tweet his fieldwork faux pas, he did mention it along with his findings in a paper published Thursday in the journal Current Biology.
This is the first time anyone has suggested that a frog can be venomous, according to Edmund Brodie, a biologist from Utah State University and co-author on the paper. Hundreds of species of frogs are poisonous, like the Amazon’s brightly colored poison dart frog. But to be classified as venomous, a creature must have a method by which it can inflict that poison into a victim. For these two frogs, flailing the head suffices.
“It all started because Carlos was out collecting them and got jabbed in the hand by one of them,” Dr. Brodie said. “This is how one makes those ‘Eureka’ discoveries!”
—NICHOLAS ST. FLEUR
—NICHOLAS ST. FLEUR
AUGUST 7, 2015
What’s That Bubble? A Dying Star’s Glowing Remains
A gigantic glowing bubble in the constellation Hydra is actually a planetary nebula, a gas cloud formed from a dying star. A striking new picture of the so-called Southern Owl Nebula was captured by the European Southern Observatory’s Very Large Telescope in Chile. The orb has a diameter of almost four light-years. A planetary nebula last tens of thousands of years and then fades, leaving behind a stellar remnant that persists for about a billion years. The remnant then becomes a hot, dense white dwarf that cools over billions of years.
—SINDYA N. BHANOO
—SINDYA N. BHANOO
An earlier version of this post misstated part of the name of the organization that runs the telescope. It is the European Southern Observatory, not the European Space Observatory.
—“Bear viewing never gets boring.”
Jenna Schnuer on her IRL visit to Katmai National Park in Alaska, where the bears onExplore.org's bear-cams live.
AUGUST 7, 2015
The Radioactive Heart of the New Horizons Spacecraft to Pluto
The radioactive element plutonium gets its name from Pluto. So it is only fitting that a variation of the unstable metal, known as plutonium 238, would be at the heart of the New Horizons mission that flew past the former ninth planet last month.
This isotope releases energy in the form of heat as it decays. New Horizons transforms the heat energy into electricity capable of powering its voyage through the solar system.
After directing the spacecraft beyond the dwarf planet, that decaying heart was “beating, and beating well, and beating still,” said Jim Green, the director of the planetary science division at NASA headquarters, in a news conference after the flyby. “Radioisotope power enables us to move further out into the solar system, and it’s on a trajectory to leave.”
By now, New Horizons has gone about 15 million miles beyond Pluto, and is steadily beaming data from the flyby back to Earth.
The energy conversion takes place in the craft's 125-pound generator, called the General Purpose Heat Source-Radioisotope Thermoelectric Generator. New Horizons was stocked with 24 pounds of plutonium that produced about 240 watts of electricity when it left Earth in 2006, according to Ryan Bechtel, an engineer from the Department of Energy who works on space nuclear power. During the Pluto flyby the battery produced 202 watts, Mr. Bechtel said.
The power will continue to decrease as the metal decays, but there is enough of it to command the probe for another 20 years, according to Curt Niebur, a NASA program scientist on the New Horizons mission.
In that time the spacecraft will have traveled 5.6 billion miles past Pluto. Its plutonium heart will beat softer with every mile, until it decreases to the point where there is no longer enough to support the systems that operate the spacecraft and communicate with Earth, according to Dr. Niebur.
When that happens, the craft will continue combing through the cosmos at the same speed and in the same direction until something stops it, Dr. Niebur said. But if nothing in the vast emptiness of space impedes New Horizons' travels, then "it will just keep going, forever, all alone in the deep dark," he said.
—NICHOLAS ST. FLEUR
—NICHOLAS ST. FLEUR
AUGUST 5, 2015
Giant Tortoises Island Hop Across the Galápagos
Giant Galápagos tortoises, the world’s biggest, have had it rough. Thanks to pirates and whalers eating them and to non-native species like goats destroying their habitat, four of the 14 documented species are extinct. Most recently, the Pinta species vanished with the 2012 death of Lonesome George, after decades of attempts to get him to reproduce.
But the tortoises emerging from the crates above represent a milestone in tortoise restoration efforts. They are among 201 tortoises recently released ontoSanta Fe Island, which lost its tortoise species a century and a half ago.
“We wanted to do this for a long time,” said Linda Cayot, the science adviser for the Galápagos Conservancy, which, in collaboration with the Galapagos National Park Directorate, runs the Giant Tortoise Restoration Initiative. It wasn’t easy. Without any Santa Fe tortoises left (nobody alive now has actually seen them – their existence is known mainly from whalers’ logbooks and museum-preserved bone fragments), conservationists turned to a close genetic relative: tortoises from Española Island.
Española is itself a tortoise success story. By the 1960s, the island was so sparsely populated that its 12 females and two males never even crossed paths to mate. Brought to a breeding center on another island, they were joined by a male from the San Diego Zoo, who some naturalists nicknamed “Diego” and who “became the major stud,” Dr. Cayot said. The other two males stepped up too.
The tortoise eggs were incubated, at temperatures adjusted to hatch two females for every male (slightly warmer eggs produce females). At about age 4, able to withstand predators, babies were placed on Española, which now has about 1,000 tortoises, Dr. Cayot said. Santa Fe was next.
Before dawn on June 27, 201 Española tortoises between 4 and 10 years old were ferried there and carried, up to 12 in a backpack, on a long rocky trail to Santa Fe’s interior. The 30 oldest, including two pictured above, have radio transmitters glued to their carapaces.
Periodically, conservationists will find those tortoises to study their movement and effects on vegetation, Dr. Cayot said, noting that about half of repatriated tortoises die because of scarcity of food and water. Those who find what they need are likely to live a century or more.
—PAM BELLUCK
—PAM BELLUCK
—“Our traditional foods are killing our people. But without our traditional foods, we die as a culture.”
Vi Waghiyi, who lives on St. Lawrence Island in a remote part of Alaska, home to one of thebiggest and most polluted U.S. military sites.
AUGUST 5, 2015
Looking for Clues to Early Life on Earth in an Underwater Volcano
That was pretty glorious right? Go back and watch it again. This time look carefully for long, white plumes drifting down the island’s coast. This isn’t sand kicked up by the waves, it’s actually swaths of bacteria thriving off shallow water hydrothermal vents that continuously spew sulfur and carbon dioxide. Scientists think the vents and the life around them may offer some clues to how and where life on Earth started.
The vents are located off Kueishantao Island, near Taiwan’s north east coast. Underwater, the vents look like bubbling chimneys. They heat the water to 212 degrees Fahrenheit and drive the water’s pH way down, to between 1 and 3. (Normal pH of the ocean is around 8.)
“This is the most extreme environment known to humans and oceans in terms of pH, that we know,” said Mario Lebrato, a Spanish oceanographer studying the vents along with a team of scientists funded by the German Ministry of Research, Christian-Albrechts-Universität zu Kiel, and the National Taiwan Ocean University.
Normally these conditions would make it difficult for sealife, but what is so unusual, Dr. Lebrato said, is that the area around the vents is full of crabs and corals.
Dr. Lebrato said the scientists want to know what biological traits allow the organisms to survive. “Life on Earth,” he said, “may have started in similar volcanic sites.”
—EMILY HAGER
—EMILY HAGER
See a video you want explained? Let us know atsummerofscience@nytimes.com.
—“Many men think that women are just nagging. But it’s because of their physiology.”
Joost van Hoof, a building physicist at Fontys University of Applied Sciences in the Netherlands, commenting on a study of office buildings and the gender-biased formula used to set their temperatures.
AUGUST 3, 2015
Q&A: Is There Such a Thing as a Half Moon?
Q. On the weather and astronomy page, I saw a “first-quarter moon” depicted as a moon with a vertical slice off the left side. I had always thought of this as a half moon. If it is a quarter moon, is there such a thing as a half moon?
A. The half-illuminated disk of the moon that we see and often refer to informally as a half moon is a quarter of the way along its journey in time from new moon (dark) to crescent moon to full moon (fully illuminated) and back again. It is also a quarter of the way along the moon’s journey in space as it orbits Earth. For that reason, modern astronomers refer to this phase as the first-quarter moon. They also refer to a later “half moon” phase, seen with the vertical slice off the right side, as the third-quarter moon. (The sides are reversed when viewed from the Southern Hemisphere.)
“Half moon” was a familiar term to poets like Shakespeare (1564-1619) and to the Dutchmen who called Henry Hudson’s ship the Halve Maen when it sailed into New York Harbor in 1609. But to confuse matters further, such older sources were often referring to the crescent moon, either waxing or waning.
In reality, of course, exactly half the surface of the moon is illuminated by the sun at all times. What waxes and wanes is not the moon itself but the part of the illuminated side that can be seen by observers on Earth, owing to the changing angles formed by the sun, Earth and the moon.
—C. CLAIBORNE RAY
—C. CLAIBORNE RAY
Send your questions to C. Claiborne Ray atquestions@nytimes.com. Questions of general interest will be answered, but requests for medical advice cannot be honored and unpublished letters cannot be answered individually.
AUGUST 3, 2015
Painting by Numbers, With Genetically Modified Yeast
This is no Seurat. It’s not an Andy Warhol. And it’s not your grandmother's cross-stitch, either. Scientists at NYU Langone Medical Center have genetically altered basic yeast and created these images in living color. This is a live yeast portrait of Gregor Mendel, far right, the ultimate nod to the father of modern genetics.
For centuries, humans have played around with yeast. In ancient days, we domesticated it to make beer and bread. This artwork is just a way to visualize the next frontier of yeast manipulation.
A few years ago, the geneticist Dr. Jef Boeke and his laboratory at NYU got together with researchers worldwide to synthetically recreate the 16-chromosome genome of brewer’s yeast. The goal of the effort, called Synthetic Yeast 2.0, is to better understand “the complicated web of genetic interactions that underlie all biological processes,” Dr. Boeke said.
Last year, the research group made its first breakthrough when they created a designer chromosome called “SynIII.” The yeast still worked with this synthetic chromosome, even after 50,000 changes to the original chromosome they manipulated.
Although Dr. Boeke’s “biopointillism,” revealed at a New York Genome Center meeting earlier this month, isn’t part of Synthetic Yeast 2.0, the artwork shows that dabbling with yeast genomes can produce phenotypic, if not behavioral changes.
Naturally, basic baker’s yeast is off-white, but by adding just one gene that produces red fluorescent protein, Dr. Boeke’s lab made it red. To get orange and yellow, they altered genes to pump out beta carotene, the pigment found in carrots. Purple was hard, and green still isn’t perfect. To create the images you see here, a robot picked up tiny droplets of color-producing yeast strains and used sound waves to blast them upward into preprogrammed cells on an agar growth plate. The scientists then incubated the plate, and the colors got stronger as the yeast grew.
The lab can make 10 colors in all, and Dr. Boeke challenges every new member of his lab to add a color to the palette. Dr. Boeke said he was interested in developing yeast strains that could communicate and signal color changes, say from red to pink, when in proximity to one another.
Just for the record, this doesn’t mean you’re going to see purple beer or fuschia bread. Dr. Boeke hasn’t tried it, but he said there was not enough yeast used in the products for the color to show up.
—JOANNA KLEIN
—JOANNA KLEIN
AUGUST 3, 2015
An Extraordinary Humpback Whale Sighting in Alaska
On July 12, researchers aboard a ship called the Northern Song spotted a humpback whale lunge feeding and enjoying some krill in Frederick Sound, Alaska.
It was no ordinary sighting, and the scientists were ecstatic: They say the observation is only the most recent in the longest string of sightings of any humpback in the world.
The whale, whom the researchers named Old Timer, was first seen in Lynn Canal in southeast Alaska 44 years ago by Charles Jurasz, a pioneer in whale research. Old Timer was already fully grown. He is believed to be at least 50 years old now.
“It’s really a celebration of whales since humans largely have stopped hunting them,” said Adam Pack, a biologist at the University of Hawaii and one of the researchers who identified Old Timer.
The whale was immediately recognizable, he said: “Some of these whales have such distinct patterns. It lifted its tail flukes, and we saw the underside.”
In 1990, Old Timer was spotted off the coast of Hawaii escorting a mother-calf pair. He was observed again in 2006, defending his position next to a lone female from other competing males. That sighting confirmed he was male, Dr. Pack said.
Long-term records of sightings help researchers learn more about whales’ fidelity to particular habitats, migratory patterns, female reproductive rates and the behavioral roles that the whales adopt.
—SINDYA N. BHANOO
—SINDYA N. BHANOO
—“By heavens, if this isn’t a sign of climate change, then what is climate change going to bring?”
Peter J. Goldmark, Washington’s commissioner of public lands, on this year's wildfires.
AUGUST 2, 2015
Images on Empire State Building Bring Light to Endangered Species
When the sun sets over New York City, the colorful lights atop the Empire State Building are usually one of the most striking displays across Manhattan’s dark skies. But on Saturday night, that light show was upstaged by another kind of display: projections of images of endangered species lower down on the iconic midtown office tower.
This video captured excerpts of the work of Louie Psihoyos and Travis Threlkel, the artists who cast digital images of a variety of threatened animal species across the Empire State Building’s south face on Saturday. Mr. Psihoyosexplained that they had set out to do “the most dramatic thing we could do to get the world to know about what we’re losing.”
To make their statement, the artists used 40 projectors on the roof of another building a few blocks south. And whether the project succeeded in expanding awareness of threats to the planet's biodiversity, it made an impression on some of the people who gazed upon it firsthand.
“Witnessed some spectacular Big [Apple] magic last night,” wrote Becca Zoler, an Instagram user, with a photo she posted of the display.
JULY 31, 2015
This Lifeguard Sees a Drowning Child, Do You?
Can you spot the drowning child in the image here? An average of 10 people a day die from unintentional drowning according to the Centers for Disease Control and Prevention, but often it’s a quiet struggle that hardly resembles the dramatic affair we see on television.
Computer programmer Francisco Saldaña created the simple educational gamespotthedrowningchild.com to help people recognize the deadly situation. A person who is drowning is physiologically incapable of calling out or waving for help – meaning often there is little noise or splash.
In his marine safety guide Mario Vittone, a Coast Guard veteran, describes some things to look for instead:
- The individual’s mouth bobs above and below the surface while the body remains upright without evidence of kicking.
- The individual’s arms spread to the side and push down against the water to try and push their mouths out of the water.
The videos that Mr. Saldaña used show lifeguards successfully rescuing children from drowning and come from the YouTube channel of the Genesis Project in Charleston County, which aims to reduce the number of drownings in rural areas by providing access to swimming and water safety classes.
—ALBERT SUN
—ALBERT SUN
JULY 31, 2015
What’s That Science Thing: Bacteria Edition
In this photo, a bacterial colony rests atop a gridded surface. That gridded surface is:
A. A bacterial sieve that separates bigger pathogens from smaller ones.
B. A type of camera for deriving images from certain varieties of molecules.
C. A microbial grater used to thinly slice samples for observation under a microscope.
D. A coordinate plane to track the location of individual bacteria.
A. A bacterial sieve that separates bigger pathogens from smaller ones.
B. A type of camera for deriving images from certain varieties of molecules.
C. A microbial grater used to thinly slice samples for observation under a microscope.
D. A coordinate plane to track the location of individual bacteria.
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