Exam 19: Star Formation: A Traumatic Birth

What happens when an interstellar cloud fragment shrinks?

Stars evolve to the upper left along the main sequence,after forming in the middle.

During stage 3 of star formation,the dense,opaque region at the center of the cloud is called a:

When a typical open cluster forms,which type of stars are formed most often?

A stage 4 object can be plotted on the H-R diagram.At this stage,the star will appear:

In terms of Jupiter masses,what is the range of brown dwarfs? What are objects above and below this range called?

Besides mass the other factor that influences where a star appears on the main sequence is:

The fundamental difference between a protostar and a star is that the latter has nuclear fusion as its energy source and the former does not.

The single most important determinant of the temperature,density,radius,luminosity,and pace of evolution of a protostar is its:

Contrast the brightest stars of young open and old globular clusters.

After stage 3 in star formation,the protostar develops a surface better known as a(n)________.

Most stars in our part of the Galaxy are formed:

During the Kelvin-Helmholtz contraction phase,a protostar has a much ________ brightness as compared to the Sun.

The Great Explosion of Eta Carinae expelled about ________ solar masses of material and released about as much visible energy as a supernova.

Eta Carinae is an example of a:

How are T Tauri stars characterized observationally?

Objects which have contracted,but are of too little mass to establish thermonuclear reactions in their cores,are ________,which slowly continue to cool.

Which statement about the stages of starbirth is FALSE?

To deduce the interior conditions of the dense regions in which stars form,it is necessary for astronomers to observe in the ________ part of the spectrum.

What are thought to be some possible causes of triggering the contraction of an interstellar cloud?