Taxonomy term

News

Second stars can distort planet size estimates

When light from a star is blocked by another celestial body — as when the moon obstructed light from the much-larger sun during the recent solar eclipse — astronomers can estimate the density of exoplanets that orbit the star. And from the density, they can determine whether a planet is rocky like Earth or gaseous like Jupiter. But a new study in the Astronomical Journal shows that such density assessments, which are normally calculated from the size of the planet, may be skewed by the presence of “hidden” stars.

08 Nov 2017

Humans arrived Down Under earlier than thought

Analysis of sediments surrounding a trove of artifacts discovered in northern Australia suggests the first humans arrived on the continent about 10,000 years earlier than previously thought, a finding that has implications for the hypothesized role of humans in the extinctions of Australian megafauna.

07 Nov 2017

Pharmaceuticals in urban sediments reveal wastewater treatment effectiveness

People take pills to relieve headaches or syrups to ease a hacking cough, and eventually these medications can make their way into streams and rivers around the world as humans excrete the chemicals. Scientists are now using concentrations of common pharmaceutical products (PPs) in river sediments in Orléans, France, to determine how effective four water treatment plants have been at removing chemicals from the environment.

03 Nov 2017

When agriculture went to our heads

The dawn of agriculture left an indelible mark on early human societies, and a new study finds that eating softer, cultivated foods subtly changed the shape of human skulls. Scientists have long suspected that the transition from hunting and foraging to farming and raising livestock would have affected our skulls, specifically the mandible and other anatomy involved in chewing, but quantifying such changes has proven difficult.

01 Nov 2017

Northern Finns didn't starve during Little Ice Age

Today, Finland’s Northern Ostrobothnia region is one of the northernmost places in Europe that can support agriculture. But how this region fared during the Little Ice Age — a period of globally cooler temperatures that lasted roughly from A.D. 1300 to 1850 — is unknown. Scientists assume the climatic cooling would have adversely affected food supplies. Now, however, the discovery of a mysterious medieval cemetery in northern Finland dating to the middle of the Little Ice Age is offering clues that the inhabitants were well fed and well suited to the northern clime.

31 Oct 2017

How long will the lava flow? Predicting eruption durations with satellite monitoring

If you live near a lava-spewing volcano, it could be helpful to know just how long molten rock might flow during a fiery eruption. In a new study, scientists report that they can calculate how long lava-flowing eruptions might last based on satellite data.

27 Oct 2017

Another whiptail dinosaur added to sauropod family tree

With their massive size, long necks and whip-like tails, the sauropods are one of the most recognizable dinosaur groups. They grew as large as 100 metric tons, and it seems their huge frames were an effective adaptation: The sauropods were among the most diverse dinosaur groups, with more than 15 species known from North America alone. That list is now one species longer, with the identification of a new species based on a specimen found in Wyoming in 1995.

25 Oct 2017

Mangroves sprouted in Arctic during Eocene

Mangrove trees, which today thrive in tropical and subtropical climates in the low and midlatitudes, grew in the high Russian Arctic about 56 million years ago, scientists reported in Geology. It’s the northernmost occurrence of mangrove trees ever documented.

24 Oct 2017

Can distant earthquakes trigger submarine landslides?

Large earthquakes can nudge both nearby and distant faults closer to failure, sometimes setting off additional earthquakes halfway around the world. New evidence from the Cascadia Subduction Zone suggests that large seismic events can also trigger submarine landslides, called turbidity currents, perhaps as far as 13,500 kilometers away. If true, researchers say such long-distance connections could complicate interpretations of paleoseismic records from the Cascadia margin and elsewhere that rely on data from turbidites — the stratified remains of the underwater slides — to piece together when past local earthquakes occurred. But not everyone is convinced that long-distance landslide triggering is possible.

23 Oct 2017

Microbes care about energy efficiency

Microbes live in some of the most extreme environments on Earth, from the crushing depths of deep-sea trenches to scalding geothermal springs. Part of the reason microbes thrive in many different environments is their ability to use a variety of energy sources — including light, organic matter, and inorganic materials like hydrogen, sulfur, and iron — to power the metabolic reactions that allow them to grow and survive.

20 Oct 2017

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