Use the drop-down menus to complete the statements about the death of stars.
when a supergiant explodes, a
occurs.
a supernova may leave behind a
, which is the size of a large city.
when the outer portion of a red giant expands and is blown away, a
vis left behind.
the most-massive stars may become
. which are not directly detectable.

Supernova , Neutron star , White dwarf , Black holes

Explanation:

A supernova is a celestial body that originated after the explosion of a supergiant star whose mass is approximately 10 times the mass of the sun. In the formation of a supernova, all hydrogen is consumed and a particular star suddenly increases in brightness, with variations that can reach 19 magnitudes (about 100 times brighter than a new one).

Neutron star is a stage in the life of very large stars that, after consuming all the hydrogen in its nucleus and exploding into a supernova, can become an extremely dense and compact celestial body where there are no more atoms but a cluster of neutrons. Hence the name: neutron star. In other words, a supernova can leave behind the star Neutron, which is the size of a big city.

When a star with mass up to about 8 times the mass of our Sun depletes its “fuel,” that is, depletes hydrogen in its nucleus, the star's nucleus becomes essentially helium. At this stage the star expands into a giant red star. The outer layers still fuse hydrogen to helium, unlike its nucleus.

Later in the nucleus, the helium fuses into carbon and other heavy elements appear. The fusion process thus ends and the core contracts by its own force of gravity. However the outer layers of the red giant star are expelled, forming a planetary nebula. At this point we have a planetary nebula surrounding a small but very dense celestial body, a white dwarf. A white dwarf is therefore the core of what was a giant red star.

Black holes are very large celestial objects - some of them hundreds of times the mass of the Sun - that occupy a very small space. Its gravitational field is so intense that not even the speed of light is greater than its escape velocity. With this, the light that enters a black hole can no longer come out, so that it cannot be observed by the usual techniques that analyze the light emitted or reflected by the celestial objects.