Galaxies Coming Of Age In Cosmic Blobs

The “coming of age” of galaxies and black holes has been pinpointed, thanks to new data from NASA’s Chandra X-ray Observatory and other telescopes. This discovery helps resolve the true nature of gigantic blobs of gas observed around very young galaxies.

About a decade ago, astronomers discovered immense reservoirs of hydrogen gas — which they named “blobs” – while conducting surveys of young distant galaxies. The blobs are glowing brightly in optical light, but the source of immense energy required to power this glow and the nature of these objects were unclear.

A long observation from Chandra has identified the source of this energy for the first time. The X-ray data show that a significant source of power within these colossal structures is from growing supermassive black holes partially obscured by dense layers of dust and gas. The fireworks of star formation in galaxies are also seen to play an important role, thanks to Spitzer Space Telescope and ground-based observations.

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Global Map Of Ammonia Emissions Measured From Space Reveals New Hotspots

Distribution of ammonia in 2008, measured using the IASI instrument on board the /MetOp satellite, superimposed on an image of Europe obtained on August 30, 2008 by MODIS. Yellow to red colors indicate regions with high ammonia concentrations. The white structures are clouds. (Credit: Copyright Image MODIS Copyright L. Gonzalez/C. Deroo LOA; Image IASI Copyright ULB & INSU-CNRS)

The first complete map of global ammonia emissions has recently been achieved using to satellite data. It reveals an underestimation of some of the ammonia concentrations detected by current inventories, and identifies new hotspots.This work, carried out by a team from LATMOS-IPSL (CNRS/UPMC/UVSQ) in collaboration with Belgian researchers from the Université Libre de Bruxelles, was facilitated by the infrared measurements of the French IASI instrument, part of the MetOp meteorological satellite developed by CNES.

Ammonia (NH3) contributes significantly to the formation of the particles that give rise to pollution episodes. It mainly emanates from the use of agricultural fertilizers and increasingly intensified livestock breeding practices. Ammonia is the least well-understood pollutant regulated by European Directives on air quality. Mapping of its emissions are imprecise and systematic global monitoring of this compound is difficult. Once emitted, ammonia only remains in the atmosphere for a short period but triggers a cascade of environmental effects. At a local level, high ammonia concentrations affect fauna, flora and air quality.

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Patagonian glaciers melting at unprecedented rates

The latest research expedition to the Southern Patagonia Ice Field revealed that alpine glaciers in the Chilean and Argentine Andes are disappearing at much faster rates than previously anticipated by the scientific community.The scientists discovered that the masses of ice in the Patagonia are melting in larger proportions and in much higher alpine zones than in any other part of the world, including Alaska and the Himalayas. Glacier ice accounts for around 75 percent of the world’s fresh water.

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Dinosaurs May Have Been Smaller Than Previously Thought

The largest animals ever to have walked the face of the earth may not have been as big as previously thought, reveals a paper published  in the Zoological Society of London’s Journal of Zoology.Scientists have discovered that the original statistical model used to calculate dinosaur mass is flawed, suggesting dinosaurs have been oversized.Widely cited estimates for the mass of Apatosaurus louisae, one of the largest of the dinosaurs, may be double that of its actual mass (38 tonnes vs. 18 tonnes).

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