What do we know about these rather intense gravitational regions?

What do we know about these rather intense gravitational regions?
Gemma Lavender gets to the bottom of this question for us.
A fossilised remnant of our galaxy, harbouring stars of hugely different ages, has been found
An ancient population of stars has been discovered at the centre of our galaxy
If you journeyed to the centre of the Earth, would your weight change?