(a) The shape of an elliptical galaxy can be quantified by using the ratio of the semi-major and semi-minor axes. i. Wri

[answerhappygod]

A The Shape Of An Elliptical Galaxy Can Be Quantified By Using The Ratio Of The Semi Major And Semi Minor Axes I Wri 1 (220.13 KiB) Viewed 10 times

(a) The shape of an elliptical galaxy can be quantified by using the ratio of the semi-major and semi-minor axes. i. Write down how this ratio is related to the designation of an elliptical within the Hubble classification scheme. ii. State three possible intrinsic three-dimensional shapes of ellip- tical galaxies. iii. Explain the location of ellipticals and spirals in general on a galaxy colour-magnitude diagram. (b) The object 3C 236 is a low-redshift Fanaroff and Riley class II radio galaxy which possesses a host galaxy with a redshift of 0.10. = i. Estimate the distance to 3C 236 in megaparsecs assuming a Hubble constant of H. 70 km s-1 Mpc-1. ii. Determine the projected size of the radio galaxy in mega- parsecs given the angular extent of 0.46 arcminutes. iii. State how this compares to the size of galaxies and clusters. a (c) The radio galaxy is powered by a black hole. State the formula for the Schwarzschild radius of a black hole and show that its value is less than one Astronomical Unit for a supermassive black hole of mass 107 M..