There’s a massive empty spot in the universe

There’s a massive empty spot in the universe
Astronomers have found an enormous empty place in the universe—a hole nearly a billion light-years across with no stars, no galaxies, no gases and not even never-seen dark matter. The void, considered a “cold spot” in the universe, dwarfs all other similar empty places.
The researchers identified the massive hole by studying data from the Very Large Array radio telescope in New Mexico. Their work, which has been accepted for publication in the Astrophysical Journal, showed a large and surprising drop in the number of galaxies in a region of the sky in the constellation Eridanus.
“Not only has no one ever found a void this big, but we never even expected to find one this size,” said Lawrence Rudnick of the University of Minnesota. “What we’ve found is not normal, based on either observational studies or on computer simulations of the large-scale evolution of the universe,” said co-author of the study and colleague Lilya Williams.

World’s grasslands losing out
Rising levels of carbon dioxide in the atmosphere might be contributing to the conversion of the world’s grasslands into a landscape of useless woody shrubs, according to a study released on Monday. By artificially doubling carbon dioxide levels over enclosed sections of the Colorado prairie in the US, researchers created a dramatic rise in Artemisia frigida, a commonly shrub. The study paints a harsh picture of what grazing lands could look like in 2100, when some estimates project carbon dioxide levels will be double today’s. “To the extent that C02 is driving this conversion, this suggests the problem is going to become more intractable in the future,” said Jack Morgan, a plant physiologist at the US Department of Agriculture and lead author of the study, published in the Proceedings of the National Academy of Sciences. Since at least the dawn of the Industrial Revolution, when carbon dioxide levels began to rise with the burning of fossil fuels, large swaths of the world’s seasonal grasses favoured by livestock have been replaced by woody shrubs. The concentration of carbon dioxide has risen from 280 ppm at the end of the 18th century to 385 ppm today.

Butterfly at risk in Canada
The alpine Apollo butterfly is beginning to feel the heat of global warming. Climate change has fostered expansion of forests in the Canadian Rocky Mountains, and the encroachment of trees into meadows where the butterflies live has put the colourful creatures at risk, researchers at the University of Alberta said. The butterflies, a species also known as Parnassius, rely on sunlight to generate the body heat that they need to fly. But the creeping forest has made their habitat smaller and shadier, limiting the butterflies’ ability to move and isolating them from their counterparts in nearby meadows, the study found. That shrinks the population and curtails movement between meadows, which could put them at risk of local extinction, researchers argue in the study published in the Proceedings of the National Academy of Sciences. Although not a threatened species, the butterflies—or at least local groups of them—could be wiped out by a particularly cold winter or summer, researchers said.