PLATO SAID THAT astronomy compels the “soul to look upward, and leads us from this world to another.”
Space has always been fascinating to us down here on Earth – the planets, the stars, the galaxies and the unimaginable beast that is the black hole.
So come with us now as we take a journey to debunk the myths and unearth the realities of the most fascinating object in outer space…
What is a black hole anyway?
Don’t let the name fool you – black holes aren’t just empty space. It fact, they’re anything but. They’re a great amount of matter packed into a very small area. “Think of a star ten times more massive than the Sun squeezed into a sphere approximately the diameter of New York City,” says NASA. They’re succinctly described as a region of spacetime from which gravity prevents anything from escaping (including light, hence the name).
When did we learn about them?
No sniggering please – the term “black hole” was only coined in 1967, by a Princeton physicist John Wheeler. Despite that, the idea pre-dated Wheeler by quite some time and was predicted by Einstein (who showed with his general relativity theory that when a star dies, it leaves behind a dense core that can overwhelm all other forces).
The idea of a body so massive that even light could not escape it was first suggested by John Michell – way, way back in 1783. Nice work, John.
Alright – how much do we know?
Black holes cannot be seen or observed by scientists – not even with telescopes that detect X-rays, light, or other forms of electromagnetic radiation. But (and it’s a big “but”), their presence can be inferred and studied by detecting their effect on matter nearby.
NASA gives the example of a black hole interacting with interstellar matter – with the black hole drawing and pulling matter inward in a process known as “accretion”. If a normal star passes nearby a black hole, the black hole can literally tear the star apart by pulling it in. Eek.
So – let’s cut to the chase. Could we ever travel through them?
Black holes are so massive and powerful that they warp space and time. Stephen Hawking once declared that there are times when fact is stranger than fiction, and “nowhere is this more true than in the case of black holes”. It’s difficult for any of us to really wrap our heads around what black holes mean.
According to the astrophysicist Charles Liu, if you were to step into a black hole, you would wind up “like toothpaste being extruded out of the tube”. Crossing a black hole’s horizon means that gravity takes on strange effects – your feet would be closer to the black hole than your head, so would be under more gravitational pull. So you’d stretch out like a Refresher bar. Not pretty. Time would slow down too, so you’d be hanging around like putty for quite some time.
Hawking says that “it might be possible” to fall into a black hole and come out in another universe altogether. There is some evidence for things coming back out of black holes once they get pulled in – but definitely not where you started. So, if you want to travel in a black hole, you’d have to wave goodbye to Earth. Forever…
Would you do it?
Interstellar, directed by Christopher Nolan and starring Matthew McConaughey, Anne Hathaway, Jessica Chastain and Michael Caine, is in cinemas this Friday the 7th of November. It features a team of space travellers who pass through a wormhole to find a new, habitable planet. Check it out this weekend on theatrical release, including IMAX.
