If the Hipparcos Satellite Measures the Parallax Motion of a Star

question 12

Multiple Choice

If the Hipparcos satellite measures the parallax motion of a star against the background stars and concludes that the star has a parallax of 0.004 arcsec,how far is that star from Earth?

• A) 250 pc or 800 ly
• B) 0.004 pc or 0.013 ly
• C) 25 pc or 81 ly
• D) 400 pc or 1300 ly

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Definitions:

Reversibility

The concept that certain processes can be undone, returning to the original state by reversing the process that caused the change.

Egocentrism

A cognitive bias where an individual has difficulty understanding or assuming any perspective other than their own, often discussed in the context of child development.

Simple Reflexes

Basic, involuntary responses to stimuli, such as the knee-jerk reflex, that are mediated by the spinal cord and brainstem.

Cognitive Structures

Mental frameworks or patterns that help individuals organize and interpret information.