Question

what kind of star is the smallest with a typicle one being only about 20 miles across

Answer 1

Thanks for the question!

It is definitely a very interesting question to solve and do some brainstorming.

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A Neutron star is by nature very hot and radioactive, infact, they are considered as planetary objects with a mass about 1.4 times than that of the Sun, the biggest star in the universe.

They measure between 10 and 20 km, have very high density, and have predominantly a pack of neutrons.

They have formed due to the supernova explosion of a massive star, combined with gravitational collapse altogether.

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Hope it helps and solves your query!!

Answer 2

What kind of star is the smallest , with a typical one being only 20 miles across ?

Answer : $\bold{NEUTRON \: STAR}$

Few lines-

The stars which are born from the explosive death of giant stars in supernova are known as Neutron stars.

Neutron stars are the stars which are completely made up of neutrons. These are small in size compared to other stars.

Neutron stars are  planetary objects with a mass about 1.4 or 1.5 times than the sun in the universe.

Neutron stars are planetary objects that measure between 10 and 20 km across .

These stars are very hot and highly radioactive . These stars have density about  10¹⁷kg/m³