StarDate

NGC 2273


Listen Later

The Big Dipper is low in the northeast at nightfall, ready to climb high across the north during the night. The prominent constellations Gemini and Orion are far to its upper right. But the space between them looks dark and empty. There’s just not much to see – especially from light-polluted cities. In fact, the main feature in the gap is named for its faintness. The constellation Lynx was given its name because you need the sharp eyes of a lynx to see any of its stars.

A telescope reveals some impressive sights, though. That includes the galaxy NGC 2273 – a galaxy within a galaxy. It’s about as big and as massive as our own home galaxy, the Milky Way. It has a small, tight spiral in its middle, with a wider spiral around it.

A supermassive black hole inhabits the galaxy’s heart. The black hole produces enormous amounts of radio waves. That tells us the black hole is feeding voraciously. As gas and dust spiral toward the black hole they form a wide, hot disk around it. Some of the material in the disk is funneled into “jets” that shoot into space at almost the speed of light. The jets produce radio waves.

The jets and other evidence show that the black hole is about seven and a half million times as massive as the Sun. That’s about twice as heavy as the black hole at the center of the Milky Way – an impressive zone of darkness in a dark region of the night sky.

Script by Damond Benningfield

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StarDateBy Billy Henry