Exam 12: The Interstellar Medium: Star Formation in the Milky Way

A fragment of a collapsing gas cloud that comes to equilibrium with a central temperature of 4 million K will become a

Of all forms of electromagnetic energy, radiation gives us the least access to our entire Milky Way Galaxy.

If the dark nebula are really dark, how do we know they are there?

Molecular clouds are much warmer than typical interstellar gas clouds.

Some regions along the plane of the Milky Way appear dark because

Globular clusters contain mostly blue stars.

Stars evolve along the main sequence.

Relate bipolar jets to the T- Tauri phase and Herbig- Haro objects.

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

Interstellar matter is distributed very evenly throughout the galaxy.

Molecules are found only in the clouds of the interstellar medium.

In general, Globular clusters are and than open clusters.

Which of these is NOT a consequence of dust in the interstellar medium?

Red sunset, red lunar eclipses, blue skies, and reflection nebulae are all the result of the of visible light off tiny dust particles.

Neutral hydrogen can be detected because its electron occasionally its spin and creates the 21- cm emission line for radio observers.

While many elemental spectral lines are visible, almost all molecular lines lie in the portion of the spectrum, since they are at much lower energy.

Interstellar gas is composed mainly of

The 21- cm line of hydrogen is strongly absorbed by interstellar dust.

Name four ways that the interstellar medium reveals its presence.

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