What Is the Only Way to Measure Directly the Mass

question 246

Multiple Choice

What is the only way to measure directly the mass of a star accurately?

• A) Measure its distance using trigonometric parallax and its brightness using photometry.
• B) It is not possible to measure the mass of a star.
• C) Measure its spectral type and luminosity class, then use the H-R diagram.
• D) Measure its gravitational effect on another object.

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Definitions:

Axial Skeleton

The part of the skeleton that consists of the bones of the head and trunk of a vertebrate.

Scapula

The shoulder blade.

Foraminae

Natural openings or holes, especially in bones, through which nerves and blood vessels pass.

Vertebrae

The bones in the spinal column.