Much of the Mass in Galaxies and Clusters of Galaxies

question 139

Multiple Choice

Much of the mass in galaxies and clusters of galaxies is dark matter. Which of these techniques is NOT useful for detecting evidence of this dark matter?

• A) measuring the speed of stars in their orbits around a galactic center
• B) gravitational lensing of very distant galaxies by a nearby galaxy (or cluster) and its accompanying dark matter
• C) observing the aftermath of a collision such as that in galaxy cluster 1E0657-56
• D) gravitational waves

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Definitions:

Stamina

Resistance to fatigue and illness; vigor, strength, and endurance to continue even in the face of difficult and trying conditions; a leadership quality required to create, advance, and sustain a vision.

Leadership Quality

The set of characteristics or attributes that are considered desirable in a good leader, including integrity, decision-making ability, and empathy.

Sustain a Vision

The ongoing effort to keep an organization's long-term objectives and goals clearly defined and communicated to all stakeholders.

Leader-initiated

Actions or directives that are started or established by a leader in order to guide or influence the behavior and outcomes of a group or organization.