New Scientist
Volume 207, Issue 2778, 18 September 2010, Pages 30-33
Journal home page for New Scientist

Cover Story
Somethings's been eating the stars

https://doi.org/10.1016/S0262-4079(10)62278-6 Get rights and content

A hole with hardly any stars has somehow formed in the galaxy's centre. If we could zoom in, we might find out how and test general relativity too

Section snippets

The hole story

This is a big surprise because it goes against our ideas of what ought to be happening at the galactic centre. The gravitational field around Sagittarius A* is thought to be strong enough to have herded stars into its neighbourhood over billions of years. So why aren't there more ancient stars at the galactic centre?

The most mundane explanation is that even the latest infrared telescopes are not sensitive enough to pick up their faint light. But there is also a more exciting possibility: that

Eyeing the monster

Merritt also blames Sagittarius A*, but favours a slightly different scenario. He has calculated that the orbits of stars circling Sagittarius A* will become longer and narrower over time. Eventually the stars will venture close enough to the black hole to be sucked in. Alas, this theory, too, has problems. As stars are continually forming, in order to create a void “you would have to send stars towards the supermassive black hole, then stop further stars being resupplied” to the central

Star-spotting

Unfortunately, pulsars are intrinsically faint, making them difficult to detect in the dusty galactic centre. But astronomers have just embarked on an attempt to detect all the pulsars in the Milky Way, and they are hopeful of observing pulsars in the centre of the galaxy (New Scientist, 17 March 2010, p 30).

General relativity isn't under threat just yet. So far S2 is the only star we know of that comes within 1 light day of Sagittarius A* during its orbit. To really probe the space-time around

References (0)

Cited by (0)

View full text