Supernovas are amazingly bright explosions of massive stars at the end of their lives. During the gravitational collapse, the outer layers of the star are pushed away, and chemical elements formed inside the dying star are released into space. This cosmic dust rains down onto the Earth continuously, eventually becoming part of sediments deposited in the sea.
Research published in the journal Physical Review Lettersused the concentrations of elements formed in an exploding star and preserved in oceanic sediments to hypothesize that a supernova exploded near Earth just 2.5 million years ago.
The authors, led by Dr. Gunther Korschinek from the Technical University of Munich, focused their study on ferromanganese crusts
More than 350 scientists and conservationists from 40 countries have signed a letter calling for global action to protect whales, dolphins and porpoises from extinction.
They say more than half of all species are of conservation concern, with two on the “knife-edge” of extinction.
Lack of action over polluted and over-exploited seas means that many will be declared extinct within our lifetimes, the letter says.
Even large iconic whales are not safe.
“Let this be a historic moment when realising that whales are in danger sparks a powerful wave of action from everyone: regulators, scientists, politicians and the public to save our oceans,” said Mark Simmonds.
The visiting research fellow at the University of Bristol, UK, and senior marine scientist with Humane Society International, has coordinated the letter, which has been signed by experts across the world.
On Monday September 24, at a virtual meeting hosted by the UN Headquarters in New York, 60 world leaders signed a ‘Leaders Pledge for Nature’ to stop the loss of biodiversity. Heads of State from France, Germany, UK, Netherlands, Panama signed.
Noticeably, the embattled political leaders from Japan and Mauritius were not signatories.
The Leaders Pledge in New York was part of an important UN Summit to avoid the world heading into a major period of biodiversity collapse, as planet Earth grapples with the highest extinction rates since homo sapiens became a distinct species, in what has been called the Sixth Mass Extinction. Rather than being caused by colliding asteroids or other natural phenomenon, this new age of extinction is being caused by man.
The front lines of this extinction battle is happening live on
Two groups of tiny, delicate marine organisms, sea butterflies and sea angels, were found to be surprisingly resilient—having survived dramatic global climate change and Earth’s most recent mass extinction event 66 million years ago, according to research published this week in the Proceedings of the National Academy of Sciences led by Katja Peijnenburg from Naturalis Biodiversity Center in the Netherlands.
Sea butterflies and sea angels are pteropods, abundant, floating snails that spend their entire lives in the open ocean. A remarkable example of adaptation to life in the open ocean, these mesmerizing animals can have thin shells and a snail foot transformed into two wing-like structures that enable them to ‘fly’ through the water.
Sea butterflies have been a focus for global change research because they