Stellar speech
Student:
Shuxratjon Xoshimov
Stellar evolution refers to the processes and radical changes undergone by a
star during its lifespan. It is the process through which pressure and forces of gravity
change or alter a star. Depending on its mass, the lifespan of a star can take several
million years or trillions of years.
Stars undergo several stages during their lifetime, with the first stage being
Giant Molecular Cloud. During the Giant Molecular cloud, a star begins its life at
this stage
where it is a large, dust- filled cloud of gas which is very cold. Fragments
of solar masses start collapsing due to a number of reasons, for instance,
shock
waves. The next stage is Protostar whereby the clump of gas starts collapsing and
releasing heat from its centre as it collapses. Energy from gravity is converted to
heat and it produces a lot of microwave and infrared radiation. Although it is hot
enough to glow at this point, the gas and dust block its visibility. T- Tauri is the next
stage whereby the strong winds around the star get rid of a lot of materials from the
star, including the gas and dust cocoon. It then starts fusion.
Main Sequence is the next stage whereby the
star becomes stable due to
Hydrostatic equilibrium. It fuses hydrogen to helium in its core. It spends most of its
lifetime (90%) at this stage. The next stage is the Subgiant, Red Giant, in which the
star has run out of core fusion fuel and its hydrostatic equilibrium has been disturbed.
The core reduces in size and there is rapid fusion around core stars’ shells. It
increases its energy output (Luminosity) and the gas enveloping the core is puffed
out. On the surface, the energy spreads out to cover a much larger area making it
cooler and lighter red in color. It is smaller in size than the previous stage.
After the Main Sequence, Core fusion is the next stage where the star is much
smaller in size and hot enough to begin helium fusion. It becomes bigger and more
stable at the end of this stage. Red Giant, Supergiant is the next stage whereby the
core fuel has run out once more. It may repeat stages 5 to 7, depending on mass.
Here, stellar nucleosynthesis of the heavier elements takes place. There is interaction
of nuclear fusion and gravity. After Red Giant, Supergiant,
Planetary Nebula or
Supernova is the next stage in which the outer layers are ejected as the core shrinks
and becomes more compact. Low mass stars could go the way of the planetary
nebula while high mass stars go the way of the explosive supernova.
The last stage in the lifecycle of a star is the remnant whereby the low mass
core shrinks in size to form White Dwarf. It does not collapse further due to electrons
present and is about the same size as the earth. The main forces responsible for the
formation are stars are the force of gravity and pressure..
A good graduation speech must contain interesting
material but most
importantly be delivered with confidence and enthusiasm. It will be remembered
long afterward if delivered from one’s heart. Any good graduation speech should
contain humorous anecdotes and short stories about the school year. If the speaker
is an outside person, the speaker must know the school’s traditions and speak to
those traditions. The speaker should refrain from talking only about him or herself
because the speech is for the graduates, not the speaker. Yet,
a personal touch is
important to help the audience understand why the speaker was chosen as the
commencement speaker.
Speakers can focus on several aspects of the school from which they are
graduating, such as accomplishments made
that year at the school; important
events from the school year. Speakers should offer thanks to individuals, such as
parents, teachers, friends, counselors, administrators.
Inspiring quotations can be effective if delivered properly. An audience wants to be
spoken “with” and not “at.” The speaker should research other
graduation speeches
(many are on the Internet) to help with formulating ideas. If parts of other speeches
are used, the speaker should give credit in the speaker’s speech.
