Showing 20 articles starting at article 621

< Previous 20 articles        Next 20 articles >

Categories: Ecology: Extinction, Space: General

Return to the site home page

     (via sciencedaily.com)     Original source 

If you look at massive galaxies teeming with stars, you might be forgiven in thinking they are star factories, churning out brilliant balls of gas. But actually, less evolved dwarf galaxies have bigger regions of star factories, with higher rates of star formation. Now, University of Michigan researchers have discovered the reason underlying this: These galaxies enjoy a 10-million-year delay in blowing out the gas cluttering up their environments. Star-forming regions are able to hang on to their gas and dust, allowing more stars to coalesce and evolve. In these relatively pristine dwarf galaxies, massive stars--stars about 20 to 200 times the mass of our sun--collapse into black holes instead of exploding as supernovae. But in more evolved, polluted galaxies, like our Milky Way, they are more likely to explode, thereby generating a collective superwind. Gas and dust get blasted out of the galaxy, and star formation quickly stops.   

     (via sciencedaily.com)     Original source 

Our own Milky Way galaxy is part of a much larger formation, the local Supercluster structure, which contains several massive galaxy clusters and thousands of individual galaxies. Due to its pancake-like shape, which measures almost a billion light years across, it is also referred to as the Supergalactic Plane. Why is the vast supergalactic plane teeming with only one type of galaxies? This old cosmic puzzle may now have been solved.

     (via sciencedaily.com)     Original source 

Using the James Webb Space Telescope, CECILIA Survey receives first data from galaxies forming two-to-three billion years after the Big Bang. By examining light from these 33 galaxies, researchers discovered their elemental composition and temperature. The ultra-deep spectrum revealed eight distinct elements: Hydrogen, helium, nitrogen, oxygen, silicon, sulfur, argon and nickel. The teenage galaxies also were extremely hot, reaching temperatures higher than 13,350 degrees Celsius.

     (via sciencedaily.com)     Original source 

Optical scientists have created a high-power 'Star Wars' style-laser, boosting their use in defense and for remote sensing applications.

     (via sciencedaily.com)     Original source 

Gamma-ray flares from blazars can be accompanied by high-energy neutrino emission. To better understand this phenomenon, an international research team has statistically analyzed 145 bright blazars. They constructed weekly binned light curves and utilized a Bayesian algorithm, finding that their sample was dominated by blazars with low flare duty cycles and energy fractions. The study suggests that high-energy neutrinos of blazars might be produced mainly during the flare phase.

     (via sciencedaily.com)     Original source 

Wild caviar, a pricey delicacy made from sturgeon eggs, has been illegal for decades since poaching brought the fish to the brink of extinction. Today, legal, internationally tradeable caviar can only come from farmed sturgeon, and there are strict regulations in place to help protect the species. However, by conducting genetic and isotope analyses on caviar samples from Bulgaria, Romania, Serbia, and Ukraine -- nations bordering the remaining wild sturgeon populations -- a team of sturgeon experts found evidence that these regulations are actively being broken. Their results show that half of the commercial caviar products they sampled are illegal, and some don't even contain any trace of sturgeon.

     (via sciencedaily.com)     Original source 

Australia's only vulture, and a fearsome extinct eagle, are among the earliest recorded birds of prey from the Pleistocene period more than 50,000 years ago -- and now researchers are bringing them to 'life' again.    Along with new scientific information, a bold new pictorial reconstruction of a newly named eagle and the only known Australian vulture will be unveiled at the World Heritage-listed Naracoorte Caves in South Australia's Limestone Coast this month.  

     (via sciencedaily.com)     Original source 

Nature photographers posting to social media are helping improve biodiversity conservation mapping in South Asia, and the method could go global.

     (via sciencedaily.com)     Original source 

Human trade and transport have led to the intentional and accidental introductions of non-native species outside of their natural range globally. These biological invasions can cause extinctions, cost trillions, and spread diseases. A study has investigated how many of these non-native species already exist worldwide and which species groups are particularly prone to become non-native.

     (via sciencedaily.com)     Original source 

Ancient cycad lineages that survived the extinction of the dinosaurs may have done so by relying on symbiotic bacteria in their roots to fix atmospheric nitrogen. The finding came from an effort to understand ancient atmospheres, but became an insight into plant evolution instead.

     (via sciencedaily.com)     Original source 

ALMA (Atacama Large Millimeter/submillimeter Array) has demonstrated the highest resolution yet with observations of an old star. The observations show that the star is surrounded by a ring-like structure of gas and that gas from the star is escaping to the surrounding space. Future observations with the newly demonstrated high resolution are expected to elucidate, not only the end of a star's life, but also the beginning, when planets are still forming.

     (via sciencedaily.com)     Original source 

In the geological past, several groups of crocodiles evolved towards a morphology adapted to marine life. However, the extent of these adaptations and their evolutionary trajectories remained unknown. An exhaustive study of their morphology has now shed light on the evolutionary mechanisms at work, thanks to three-dimensional reconstructions.

     (via sciencedaily.com)     Original source 

Planetary rovers, which help humanity explore other planets, can deviate from their targeted paths or get stuck due to slipping on loose soil. To combat this problem, researchers have developed a novel system for rovers to detect their slip condition from the change in the shape of their chassis. This novel technology, inspired by human muscles, can lead to advanced sensing technologies that make travel safer for unmanned vehicles.

     (via sciencedaily.com)     Original source 

A new study presents crucial findings on the feeding preferences of herbivorous fishes and the sea urchin Diadema antillarum in Little Cayman. The study sheds new light on the dynamics of these herbivores and their impact on the resilience of Caribbean coral reefs.

     (via sciencedaily.com)     Original source 

After a distant star's explosive death, an active stellar corpse was the likely source of repeated energetic flares observed over several months -- a phenomenon astronomers had never seen before, astronomers report.

     (via sciencedaily.com)     Original source 

Astronomers have used recent observations made with the James Webb Space Telescope to study the atmosphere of the nearby exoplanet WASP-107b. Peering deep into the fluffy atmosphere of WASP-107b they discovered not only water vapor and sulfur dioxide, but even silicate sand clouds. These particles reside within a dynamic atmosphere that exhibits vigorous transport of material.

     (via sciencedaily.com)     Original source 

Researchers have developed a new deep learning AI tool that generates life-like birdsongs to train bird identification tools, helping ecologists to monitor rare species in the wild.

     (via sciencedaily.com)     Original source 

Data from a NASA mission to map dark matter around galaxy clusters has been saved by a new recovery system. The system allowed the retrieval of gigabytes of information, even after communication failed and the balloon-based telescope was damaged in the landing process.

     (via sciencedaily.com)     Original source 

How did the molecular building blocks for life end up on Earth? One long-standing theory is that they could have been delivered by comets. Now, researchers have shown how comets could deposit similar building blocks to other planets in the galaxy.

     (via sciencedaily.com)     Original source 

A student has measured the optical depth of Saturn's rings using a new method based on how much sunlight reached the Cassini spacecraft while it was in the shadow of the rings.