Astronomical observations of our Milky Way galaxy indicate that it has a mass of about 8.0 x 10 solar masses. A star orbiting near the galaxy's periphery is 5.6 x 10* light-years from its center. (a) What should the orbital period (in y) of that star be? (b) If its period is 5.3 x 107 years instead, what is the mass (in solar masses) of the galaxy? Such calculations are used to imply the existence of other matter, such as a very massive black hole at the center of the Milky Way. solar masses

According to Lunar Laser Ranging experiment the average distance LM from the Earth to the Moon is approximately 3.91 x 105 km. The Moon orbits the Earth and completes one revolution relative to the stars in approximately 27.5 days (a sidereal month). Calculate the orbital velocity of the Moon in m/s. Answer: Choose...

Plaskett's binary system consists of two stars that revolve in a circular orbit about a center of mass midway between them. This statement implies that the masses of the two stars are equal (see figure below). Assume the orbital speed of each star is V = 240 km/s and the orbital period of each is 12.1 days. Find the mass M of each star. (For comparison, the mass of our Sun is 1.99 x 1030 kg.) solar masses XCM M

Problem 5: Suppose you are told that a satellite orbiting the Earth has a orbital period of 0.85 hours. a)Using the orbital characteristics of the Moon (RM = 3.84 × 105km and TM = 0.0748 y), use Kepler's laws to calculate the orbital radius for the satellite, in kilometers. b)What is unreasonable about this result?MultipleChoice   :1) This radius is unreasonable because it is smaller than the orbital radius of the Moon.2) There is nothing unreasonable about the result.3) This radius is unreasonable because it is greater than the radius of the Earth.4) This radius is unreasonable because it is greater than the orbital radius of the Moon.5) This radius is unreasonable because it is smaller than the radius of Earth.

need help with this question

A = 2 X 1025, B = 4.5 X 10-10, C = 3 X 10-6. AB/C = ?       (2) ACB = ?       (3) The Moon is approximately 400,000 km from the Earth.  An atom of a certain element has a diameter of 4 X 10-8 cm. Given 1 km = 1,000 m and 1 m = 100 cm, about how many atoms of this element can be lined up between Earth and Moon?             (4) A spherical planet has a radius of 2,000 km and a mass of 1025 kg. Calculate its density (mass/volume) in kilograms per cubic meter.           (5) How many of the atoms in Question (3) can fit within a spherical planet with a diameter of 2 X 104 km?           (6) An asteroid’s radius is 200 m and its distance from Earth is 107 km. What angle in degrees (θ) will it subtend? Use the equation  θ = 57 (diameter) / distance

Refer to this table to determine the average distance between the Earth and the Sun. Then calculate the average speed of the Earth in its orbit in kilometers per second and meters per second?

A spaceship is moving in an elliptical motion. Their position (x, y) is described by the equation (x^2)/4 + (y-5)^2 = 9 Here, x represents their horizontal position (in km) and y represents the height (in km) of the spaceship: (a) An observer at a certain instant sees the shadow of the spaceship at x = 2 km and observes that the shadow is moving with a speed of 100 km per hour in the positive x direction. The observer also notes that the spaceship is ascending at this instant. How fast is the vertical motion of the spaceship at this instant? Give an exact answer. (b) Assuming that the spaceship doesn’t alter its course, is it moving in a clockewise or counterclockwise motion? (c) The speed of the spaceship is defined by the quantity Square root ((dx/dt)^2 + (dy/dt)^2). What is the speed of the spaceship in Part (a)? You may approximate

I need help with this hw problem.

Consider the Earth's orbit around the Sun to be circular with radius R = 9.30 x 107 mi and it takes 365 days to complete one revolution. What is the distance Earth traveled for one revolution (circumference of a circle is 2??2πR )?