Question

How does the doppler method depend on the orbital inclination of a planet?

O the doppler method does not depend on the orbital inclination of a planet.
O the orbital inclination will make the spectrum fainter.
O the doppler method only works for planets in orbits that are nearly face-on to us.
O the doppler method provides the true mass of the planet only if we know the inclination of the planet's orbit.
O the doppler method provides the true mass of the planet regardless of the inclination

Answer 1

The Doppler method depends on the orbital inclination of a planet because the true mass of a planet can only be determined if the inclination is known.

Step-by-step explanation:

The Doppler method of detecting planets is reliant on measuring the radial velocity of a star, which is affected by the gravitational pull of an orbiting planet. This method allows astronomers to detect the minimum mass of the planet, but determining the exact mass requires knowledge of the orbital inclination. The true mass of a planet can only be calculated if we know the inclination of the planet's orbit.

Without this information, we can only determine a lower limit for the planet's mass. For orbits that are not edge-on, the measured radial velocity will be smaller than it would be if we could view the system edge-on, leading to an underestimation of the planet's mass. Therefore, the statement that the Doppler method provides the true mass of the planet only if we know the inclination of the planet's orbit is accurate.