jerm0225

The distant star, ∆A_6325, is traveling at 70 km/sec away from us and has a peak observed brightness at 400 nm. An exoplanet orbits ∆A_6325 in a transit orbit, causing a 1.4% brightness drop as the planet crosses the star. The ratio of the star’s radius and the planet’s radius is 145:1. The planet was determined to have a density of 2.36 g/cm3. The orbital radius of the planet is 3.14 AU and has an orbital period of 6.32 years. a) Find the mass of ∆A_6325. b) Determine the distance of the star/system, using the most inaccurate method on the intergalactic distance ladder. c) Determine the power of the star. d) Determine the intensity of the star on the exoplanet. so i dont need answers for all of these but it would be great if I knew how to get area for a orbital radius, or how to determine powers of stars or intensity, or what the inaccurate method is. I dont know what the intergalactic distance ladder is. I'm 13 years old and this is for a science olympiad application and they expect all of us to get a lot of help from online since these questions are really difficult.