A galaxy with many young stars was made by a merger about a billion years ago

the gist

NGC 2865 is an elliptical galaxy about 100 million light-years away, and ellipticals are normally full of old, dying stars. This one has a rapidly rotating disc of young stars and gas, pointing to a galaxy-wide starburst roughly a billion years ago. That burst was triggered by a merger between a spiral galaxy like the Milky Way and an elliptical about three times more massive. Fresh gas from the spiral revitalised the old stars, and cold gas torn from the spiral now forms a faint shell around the galaxy.

how it works

When galaxies collide, gravity drives gas toward their centres, where it forms stars rapidly. Gas from a gas-rich spiral can mix with an older galaxy's stars, creating new generations of young stars and leaving tidal debris behind.

so what

It shows that mergers can rejuvenate galaxies that would otherwise fade, so the shape and age of a galaxy can reveal a violent past. Ellipticals with young stars are a clue that they were not always as quiet as they look.

ESA/Hubble · CC BY 4.0

Image: ESA/Hubble & NASA Acknowledgement: Judy Schmidt

source: ESA/Hubble ↗

historyWikipediaclassic1336–1565 · Karnataka, India

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 ↗