Astronomy help 1) Suppose you could observe stellar parallax from the orbit of Neptune.

1) Would it be easier or more difficult to measure stellar distances?

a) Neptune has the greater mass and radius than Earth. Therefore, parallaxes obtained from the Neptune would be smaller, and it would be more difficult to measure stellar distances.

b) Neptune has the greater mass and radius than Earth. Therefore, parallaxes obtained from the Neptune would be greater, and it would be easier to measure stellar distances.

c) Neptune has the greater orbital distance than Earth. Therefore, parallaxes obtained from the Neptune would be smaller, and it would be more difficult to measure stellar distances.

d) Neptune has the greater orbital distance than Earth. Therefore, parallaxes obtained from the Neptune would be greater, and it would be easier to measure stellar distances.

2) How would stellar parallax observed from Neptune differ from the stellar parallax we observe from Earth?

(parallax from Neptune/parallax from earth) =

3) Describe what would happen to the surface temperature of a star if its radius doubled but there was no change in luminosity.

the answer is = Luminosity increases both with increasing radius and increasing temperature. Therefore, a lower temperature would be required to maintain the star's constant luminosity.

3) By what factor would the temperature of the star change?

(T initial / T final)=

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