Exam 15: Star Formation and the Interstellar Medium

Star formation in a molecular cloud can be slowed by the strength of its magnetic field and turbulence caused by supernovae and stellar winds from massive stars.

Warm ionized gas in the interstellar medium appears _________ when imaged in the optical region of the electromagnetic spectrum.

Where have astronomers observed the existence of planets?

For an object in hydrostatic equilibrium,if the temperature inside the object were to increase,the object would:

Sitting in a 100°F hot tub feels much hotter than standing outside on a 100°F day.This analogy illustrates why:

A young protostar is _________ than the Sun even though its surface temperature is _________.

How are typical interstellar gas clouds different from the clouds that we see in the Earth's sky?

In the interstellar medium,molecules survive only in regions with:

Why can't very bright protostars be seen in visible light?

Of the following processes at work in molecular clouds,which is the one that inevitably dominates the clouds' evolution?

Interstellar clouds are:

A surprising fact about a 1 M_⨀ protostar is that,even though nuclear reactions have not yet started in their cores,they are _________ than the Sun.

Why is it possible for self-gravity to dominate pressure in molecular clouds but not in most interstellar clouds?

The most common types of stars in our galaxy are:

A protostar is usually in hydrostatic equilibrium as its collapses.

Electronic transitions from the H₂ molecule are easily seen at radio wavelengths.

What happens as a protostar contracts?

An accretion disk forms around a collapsing protostar because infalling material must conserve:

Dust reddens starlight because:

If you wanted to observe heavy elements in the interstellar medium,where would be the best place to look?