How Far is Nanyang's Star from Earth in Parsecs?

Thread starter Scripturient
Start date Jun 19, 2022
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Astrophysics Magnitude

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The discussion focuses on calculating the distance from Earth to Nanyang's star in parsecs. A formula involving magnitudes and distance is referenced, specifically m2 - m1 = 5log(d2/d1) + Ad2. There is a clarification needed regarding the correct specification of distance, with a suggestion that d2 should be set at 1000 parsecs. The participants emphasize the importance of accurate distance measurement in the calculations. Overall, the conversation centers on resolving the distance calculation to Nanyang's star.

Jun 19, 2022

Scripturient

Homework Statement: Suppose that to a particular heliocentric 3D-Cartesian coordinate, the Earth is located at (1,0,0) A.U. You tried to observe Nanyang Star (with the same luminosity as the Sun) from the Earth. Nanyang Star is located at (1,0,1) kpc in the same coordinate system. If you obtained a visual magnitude of +17.2 from the observation, what is the coefficient of absorption, defined as the visual magnitude increase per unit distance due to interstellar matter, in the star’s direction? (It is given that Sun’s absolute magnitude is +4.83.)

Relevant Equations: Apparent Magnitude

My attempt has been attached.

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Jun 19, 2022

mjc123

Science Advisor

Homework Helper

Shouldn't you have m₂ - m₁ = 5log(d₂/d₁) + Ad₂?
And is d₂ = 1000 pc?

Jun 19, 2022

phyzguy

Science Advisor

As @mjc123 implied, you don't have d specified correctly. How far is it from Earth to Nanyang's star in pc? This is what you should use for d.

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