Climate change: US pledges to cut carbon emissions by 50-52%

The US has unveiled a bold emissions target by the end of this decade. This new target, which will be unveiled at a virtual summit of 40 global leaders, essentially doubles their previous promise.

India records the world's highest ever daily increase in Covid-19 cases amid a shortage of oxygen in hospitals; and NASA's Perseverance rover produces pure oxygen from the atmosphere of Mars.

(Photo: US President Joe Biden removes his face mask to speak about the status of coronavirus disease. Credit: Reuters.)