Is it possible that any random object can be compressed into a black hole?
It is known for a fact that all the stars in our universe give off light due to the nuclear fusion processes taking place inside them. Although it's clear that all the stars start off their lives in the same way (from gas clouds), they don't end it all equally. In fact, how they die is mainly dependent on the final mass of these stars.
It's quite simple to reason this by taking the mass of these stars. For example, if it's a star with only 0.08 solar mass, it won't even emit light and exists as a brown dwarf. For an average-sized star, like our sun, it will turn into a red giant and may turn into a white dwarf. For a supermassive star, with a mass of more than 3 to 10 times our sun, it may turn into a neutron star or a black hole. But is it only supermassive stars that can turn into a black hole? Theoretically, an object of any mass can be compressed into a black hole. There is one requirement though. The object must be compressed until its radius equals its Schwarzschild radius. 
The Schwarzschild radius is named after the German physicist Karl Schwarzschild, whose works confirmed that any mass that has a radius less than the Schwarzschild radius could be a black hole. Each object has its own specific Schwarzschild radius below which, the object turns into a black hole theoretically. Let's say that the earth is to be compressed into a black hole. The first thing required is to find the Schwarzschild radius of the earth. It is given by:
R = 2GM / c^2
where G is the universal gravitation constant, M is the mass of the earth and c is the speed of light. From this equation, we get that the Schwarzschild radius of the earth is about 1 inch !! This means that in order to compress the earth into a black hole, we need to squeeze it into a sphere of radius below 1 inch, which is very very small.
This also implies that all of the earth's mass is scooped up into a very small area, which further increases its density and thus creates a singularity. Theories predict that any object, say a person, a chair, a building etc. can be compressed into a black hole by squeezing it below its Schwarzschild radius. The more the mass of an object, the more will be its Schwarzschild radius. But in reality, only supermassive stars that have more than 10 times the solar mass actually turn out to be black holes.
Recently, I've come across an article by NASA on black holes and Schwarzschild radius which mentioned that even though any object which is less than 10 or more times the mass of the sun was to be compressed to be a black hole, it wouldn't have the gravitational pull of a black hole.
This means that the object would have the same gravitational pull as before, due to the fact that its mass is not changing (increasing) and only its density or size is changing (gravity is always directly proportional to the object's mass rather than its size or density as in the case of Schwarzschild radius).
So, it seems that even though the object gets squeezed into a black hole, it won't be showing any difference in its gravitational pull. It seems a bit twisted to me but the reasoning and logic make a lot of sense. Just to let you know that I'm still kinda figuring out the possibility behind all of it, cause obviously, science and the universe is always about figuring out possibilities!!!
**Edit : Guys, I've done some searching and asked views from astrophysics majors on whether gravity depends on density, and for the record, it doesn't !!! So, in reality, even if we manage to shrink our Earth to its Schwarzschild radius, it won't be having any change in its gravitational pull because its mass is constant.
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