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Current strategy could see badgers being targeted for many years to come.

In Himachal Pradesh, a fragile ecology, cornered by climate change, mindless tourism and unplanned development, is begging for intervention...

Study finds agriculture and pesticide use threaten relatives of world’s most important crops, considered crucial to food security<strong><br></strong>...

Could dying stars hold the secret to looking younger? New evidence from NASA's Hubble Space Telescope suggests that white dwarf stars could continue to burn hydrogen in the final stages of their lives, causing them to appear more youthful than they actually are. This discovery could have consequences for how astronomers measure the ages of star clusters, which contain the oldest known stars in the universe. These results challenge the prevalent view of white dwarfs as inert, slowly cooling burned-out stars where nuclear fusion has stopped. Now, an international group of astronomers has discovered the first evidence that white dwarfs can slow down their rate of aging by burning hydrogen on their surfaces. "We have found the first observational evidence that white dwarfs can still undergo stable thermonuclear activity," explained Jianxing Chen of the Alma Mater Studiorum Università di Bologna and the Italian National Institute for Astrophysics, who led this research. "This was quite a surprise, as it is at odds with what is commonly believed." White dwarfs have cast off their outer layers during the last stages of their lives. They are common objects in the cosmos; roughly 98% of all the stars in the universe will ultimately end up as white dwarfs, including our own Sun. Studying these cooling stages helps astronomers understand not only white dwarfs, but also their earlier stages as well. To investigate the physics underpinning white dwarf evolution, astronomers compared cooling white dwarfs in two massive collections of stars: the globular clusters M3 and M13. These two clusters share many physical properties such as age and metallicity (the abundance of heaver elements), but the populations of stars which will eventually give rise to white dwarfs are different. This makes M3 and M13 together a perfect natural laboratory in which to test how different populations of white dwarfs cool. "The superb quality of our Hubble observations provided us with a full view of the stellar populations of the two globular clusters," continued Chen. "This allowed us to really contrast how stars evolve in M3 and M13." Using Hubble's Wide Field Camera 3 the team observed M3 and M13 at near-ultraviolet wavelengths, which is ideal for finding blue and faint stellar objects in the crowded globular clusters. This allowed the researchers to compare more than 700 white dwarfs in the two clusters. They found that M3 contains standard white dwarfs, which are simply cooling stellar cores. M13, on the other hand, contains two populations of white dwarfs: standard white dwarfs and those which have managed to hold on to an outer envelope of hydrogen, allowing them to burn for longer and hence cool more slowly. Comparing their results with computer simulations of stellar evolution in M13, the researchers were able to show that roughly 70% of the white dwarfs in M13 are burning hydrogen on their surfaces, slowing down the rate at which they are cooling. The hydrogen would have been supplied by the star's outer shells leaking into space. This discovery could have consequences for how astronomers measure the ages of stars in the Milky Way galaxy. The evolution of white dwarfs has previously been modeled as a predictable cooling process. This relatively straightforward relationship between age and temperature has led astronomers to use the white dwarf cooling rate as a natural clock to determine the ages of star clusters, particularly globular and open clusters. However, white dwarfs burning hydrogen could cause these age estimates to be inaccurate by as much as one billion years. "Our discovery challenges the definition of white dwarfs as we consider a new perspective on the way in which stars get old," added Francesco Ferraro of the Alma Mater Studiorum Università di Bologna and the Italian National Institute for Astrophysics, who coordinated the study. "We are now investigating other clusters similar to M13 to further constrain the conditions which drive stars to maintain the thin hydrogen envelope which allows them to age slowly." The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C. Please follow SpaceRef on Twitter and Like us on Facebook.

Voltalia, energy company based in Paris, is recklessly developing a wind energy facility in the habitat of Endangered Lear’s Macaw, Brazil.

Bovine TB is one of the "most difficult animal health challenges" in Britain, causing farmers "considerable trauma", said environment secretary George Eustace....

Where do hurricanes come from? And how could warming oceans lead to bigger hurricanes in the future?

Up to one million species could be gone from our planet, many within decades! But an ambitious new plan to protect half the planet would stop the extinction and heal our home. Join the urgent call to protect our planet before it falls silent.

Despite a few high-profile conservation success stories—like the dramatic comeback of bald eagle populations in North America—birds of prey are in decline worldwide.

A coalition of animal rights groups filed a lawsuit Tuesday to stop Wisconsin's wolf hunt this fall and invalidate a state law mandating annual hunts, arguing the statutes don't give wildlife officials any leeway to consider population estimates.

Goffin’s cockatoos on Indonesia’s Tanimbar Island crafted three different types of tools from tree branches to obtain seeds from sea mangoes...

Australia's iconic extinct animal, the Tasmanian Tiger can be seen on video in colour for the first time.

In the age of climate crisis, survival isn’t easy.Some warm-blooded animals, like birds and elephants, are responding to this reality by changing the...

The Rivers Trust are con­ser­va­tion experts with a wealth of data and exper­tise at our fin­ger­tips.We work with our mem­ber Trusts to make our shared…...

The Galápagos Islands Seen From Orbit Press Release - Source: ESA Posted September 8, 2021 12:29 AM ©ESA The Galápagos Islands Thomas Pesquet: The Galápagos Islands are famous for their wildlife and Charles Darwin who studied the area, as well being a poster for bio-diversity �. Today the #IUCNcongress kicks off partly in Marseille, driving action to protect biodiversity and also recover and rebuild nature's part in our planet before it is too late. The Galapagos Islands are also of volcanic origin, so a great fit for #VendrediVolcan. Les îles Galápagos � célèbres pour leur biodiversité florissante qui a attiré jusqu'à Charles Darwin. Elles sont d'origine volcanique, idéal pour le #VendrediVolcan � Le congrès de l'UICN démarre aujourd'hui à Marseille. Cette organisation consacrée à la conservation de la nature agit pour protéger la biodiversité, mais aussi pour l'aider à reprendre du terrain avant qu'il ne soit trop tard. Credits: ESA/NASA-T. Pesquet Larger image Please follow SpaceRef on Twitter and Like us on Facebook. TAGS: The Galápagos Islands FILED UNDER: Biodiversity, Earth SOURCE: ESA Press Release Please enable JavaScript to view the comments powered by Disqus.

WWF’s new framework, which considers the structural barriers and enablers for nature-based solutions, offers ideas and evidence on how to boost nature’s potential to tackle the greatest challenges facing our planet.

Western Australia's forestry industry says it has been "blindsided" by a state government decision to end the logging of native forests from 2024.

Animals across the world are changing the shapes of their bodies, developing bigger beaks, legs and ears. No, this isn't an episode of Animorphs — this is the impact of climate change.

The US has accepted 2.8 million acres in offers from agricultural producers and private landowners for enrollment into the Conservation Reserve Program (CRP) in 2021.

How underground farming can help exploit extreme cold environments to grow fresh food all year round.