NASA’s Chandra Examines Milky Way at Arms’ Length - NASA Science (.gov)

Botteon et al.; Infrared: UKIDSS-GPS; Radio: ASTRON/LOFAR; Image processing: NASA/CXC/SAO/N. Astronomers have used NASA's Chandra X-ray Observatory to break down the cause of a remarkable formation of radio waves they have nicknamed the "Treble Clef" because its distinct shape strongly resembles the musical symbol. The researchers discovered the Treble Clef is likely caused by an outburst from a supermassive black hole, followed by a collision of two galaxy clusters. A paper describing the findings, led by Andrea Botteon of the National Institute for Astrophysics, or INAF, in Italy, is published Wednesday in the Astronomy & Astrophysics journal.

Astronomers have used NASA’s Chandra X-ray Observatory to break down the cause of a remarkable formation of radio waves they have nicknamed the “Treble Clef” because its distinct shape strongly resembles the musical symbol. The researchers discovered the Treble Clef is likely caused by an outburst from a supermassive black hole, followed by a collision of two galaxy clusters. A paper describing the findings, led by Andrea Botteon of the National Institute for Astrophysics, or INAF, in Italy, published Wednesday in the Astronomy & Astrophysics journal.

A day on Earth is no longer linked to the rising and setting of the sun after the world's timekeepers voted to get rid of the leap second. Since the 1970s, leap seconds have been added to global clocks 27 times, to keep atomic time in sync with Earth's daily rotation, which has slowed over billions of years. On such occasions clocks would pause for a second at 11:59:59 on New Year's Eve to allow the Earth's rotation to catch up with atomic time – which is set by the steady tick of electrons rather than planetary movement. The last one happened in 2016. But on Thursday afternoon, the General Conference on Weights and Measures in Paris approved a resolution to allow the difference between civil time (what people set their clocks to) and solar time to increase from one second to one hour. It means that there will be no more adjustments to clocks until the difference between a solar day and a 24-hour Earth atomic day has slipped by 60 minutes – a few thousand years from now.