I Observe a Galaxy That Is 100 Million Light-Years Away

question 73

Multiple Choice

I observe a galaxy that is 100 million light-years away: what do I see?

• A)the light from the galaxy as it is today,but it is blueshifted
• B)the light from the galaxy as it is today,but it is redshifted
• C)the light from the galaxy as it was 100 million years ago and it it blueshifted
• D)the light from the galaxy as it was 100 million years ago and it is redshifted
• E)Nothing: the galaxy lies beyond the cosmological horizon.

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Definitions:

Margin of Error

A measure of the uncertainty or potential error in the results of a survey or experiment, often expressed as a plus-minus figure.

Standard Deviation

A statistical measure that quantifies the amount of variation or dispersion of a set of data values.

Mean Height

The average height of a group of individuals, calculated by summing their heights and dividing by the number of individuals.

Confidence Interval

A spectrum of values obtained from statistics of a sample, which is likely to encompass the actual population parameter at a specific probability level.