Essays on White Dwarf

English astronomer W. Herschel discovered planetary nebulae in about 1783. Nebulae received the name "planetary" on account of their external similarity with the images of distant planets, light wheels of which are different from the point images of the stars. “A planetary nebula is a beautiful object created during the final stages of the life of a star whose birth mass was between 1 and 8 solar masses” (“Planetary Nebulae”). A planetary nebula is an astronomical object consisting of an ionized gas shell and the central star, a white dwarf. All planetary nebulae originate from stars that are in ...

Gravitational, electromagnetic, strong and weak nuclear forces. Gravitational force is an attraction between any two pieces of matter in the universe. Electromagnetic force is present in pieces of matter, which are able to carry electrical charge. Strong force is holding the nuclei of atoms together. Weak force is responsible for radioactive decay. Molecules are built from the atoms and atoms consist of protons, neutrons and electrons. Protons and neutrons are built of smaller particles called quarks. Electromagnetic spectrum is the range of all the light in the universe. Depending on the wavelength and frequency there are radio, micro, infrared, ...

The term ‘nova’ is the Latin name for a new star and was first used in 1573 by Tycho Brahe, a Danish astronomer. No matter how bright a new star can be, its brightness lasts for a span of weeks and then fades to obscurity. A novae normally occurs in binary systems where a normal star transfers matter onto a white dwarf. One of the major processes that occur is the piling of hydrogen onto the dwarf an aspect that generates heat. The heating continues especially on the outer layer as the dwarf ignites in a runaway. This causes a thermonuclear reaction that blows off the accumulated hydrogen ...