Answer Happy

13. In order to explain the B3 star's radial velocity variations (period = 40.3 days), the original researchers thought the star needed to orbit a black hole of comparable mass (-4 Msun). Use Kepler's Third Law (assume circular orbit) to calculate the semi-major axis of the suspected orbit. Also, calculate the angular diameter of the orbit, given Gaia's measurement of parallax (2.71 mas) and assuming a face-on perspective. Do you agree with the statement that the diameter of the star's orbit is at least 0.44 AU” (ref #1)?

Spectral type A F. GK B M Cartoon of a Hertzsprung-Russell Diagram with Luminosity Classes (not accurate) Temperature (1000 K) 25 10 & 6 Luminous supergiants 1,000,000 10 RS 100 Ron X 1,000 Rs -10 106 la 100,000 10+ 10,000 Less luminous supergiants U Rsun -5 Supergents Bright giants Іь II III 1,000 E 102 100 20.1 Rsun 0 Giants solar units] Giants 19 Main Sequence Luminosity (L_Sun) 10° Subgiants (0.01 Rson 5 Sun 0.5 0.2 0.1 Aholute Luminosity 102 White Dwarfs 0.01 White dwarfs <0.001 RS +10 0.001 104 Vio let blue white yellow Orange red 0.0001 0.0001 Run +15 OS BO KO MO M8 0.00001 DJ Jeffery WU 2001 AO FO) GO Spectral Type FIGURE 1 50,000 40,000 30,000 20,000 10,000 - 5,000 4,000 3,000 2,000 Surface temperature 7 [Kelvin) FIGURE 2 106 15 sosed 9 solar masses 104 5 solar 23345 zero-age main sequence Radius of the Einstein Ring 3 sakar masses 102 2 Todos SOLO ΔΦ (uns 1 1 solara 6 1 T criation of core hydrogen bring 10-2 A- 10 -4 DSL DLE b 6 4MG ΔΦ = α + β = + DLE Ds c2b 4MG DDLE b= c? (DSL + DLE) 4MGDSL DLE c2DLEDsL+ DLE) FIGURE 4 40000 20000 5000 2500 10000 T(K) Q= FIGURE 3 and