The Milky Way's centre hosts a four-million-solar-mass black hole surrounded by an unexpected crowd of young stars

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The Milky Way's centre hosts a four-million-solar-mass black hole surrounded by an unexpected crowd of young stars

the gist

The Galactic Center is the centre of the Milky Way, sitting about 26,000 light-years from Earth in the direction of Sagittarius. Its core holds a supermassive black hole of roughly four million times the mass of the Sun, called Sagittarius A*. Around 10 million stars lie within one parsec of the centre, mostly ageing red giants. Young, massive stars also formed in the region roughly a million years ago, which is puzzling because such stars are rarely found so close to a black hole.

how it works

Stars orbit the central black hole at high speeds, and the gravity there is extreme. The young stars are thought to have formed in a dense gas cloud that was pulled in toward the centre, which is one of the open questions in galactic astronomy.

so what

The Galactic Center is the closest large laboratory for how a supermassive black hole shapes its surroundings and how stars form under extreme conditions. Studying its young stars tests theories of how stellar nurseries survive near a gravitational giant.

fun fact

Light from the Galactic Center takes about 26,000 years to reach Earth.

Hampi was once one of the world's largest cities, until its Vijayanagara capital was destroyed in 1565

the gist

Hampi is a UNESCO World Heritage Site in Karnataka, India, with more than 1,600 surviving remains spread over 4,100 hectares. It was the capital of the Vijayanagara Empire from 1336 to 1565. Travellers from Persia and Portugal described it as a prosperous, wealthy and grand city with temples, markets and farms along the Tungabhadra River. By 1500 it was estimated to be the world's second-largest city after Beijing, and probably India's richest at the time. In 1565 a coalition of Muslim sultanates defeated the Vijayanagara Empire, its capital was conquered and destroyed, and the city was left in ruins. Hampi remains a religious centre, with the active Virupaksha Temple at its heart.

how it works

The city was built around a fortified core with temples, markets and water structures along the river, supplied by an extensive network of roads and waterworks. When the empire fell, the city was not rebuilt, so its stone monuments were left standing.

so what

Hampi shows how quickly a great city can vanish after a military defeat, and how a ruined capital can remain sacred. Its ruins give historians a view of medieval South Asia that few other sites can match.

fun fact

The name Hampi comes from Pampa, an old name for the Tungabhadra River.

From Wikipedia, the free encyclopedia · text CC BY-SA 4.0

Image: Wikimedia Commons

source: Wikipedia ↗

2 min

politicsshortCNA2:01

False allegations about Singapore’s hand in Indonesia’s markets and a made-up meeting

from CNA

CNA Verify has found close to 400 posts pushing falsehoods tying Singapore to Indonesia’s stock market rout and to a secret meeting that never took place. Together, they drew nearly 12 million views, and some were circulated by accounts that appeared to be working in concert, across multiple social media platforms.

Here’s how the disinformation campaign targeting Singapore was uncovered.

on YouTube: CNA ↗