Astronomers believe that there is a massive black hole at the center of the Milk

Question

Astronomers believe that there is a massive black hole at the center of the Milky Way galaxy. What evidence is there for that?
A group of astronomers have observed a star "S2" in a 15.2-year orbit around the center of the galaxy. They measured the period of revolution T = 15.2 years, the eccentricity of the elliptical orbit ? = 0.87, and the semimajor axis of the orbit a = 4.62 mpc. [The unit: mpc = milli-parsec = 0.001 parsec.]

(A) Calculate the mass of the compact object about which S2 is revolving.

(B) Compare the mass to the mass of the sun.

(C) Compare the radius of the orbit of S2, to the size of our solar system.

Explanation / Answer

Question 1

Nasa's Swift satellite detected the rising surge of X-rays, produced by a rare X-ray nova, last month and say it is evidence of a black hole that is part of a binary system near the Milky Way's core.

'Bright X-ray novae are so rare that they're essentially once-a-mission events and this is the first one Swift has seen,' said Neil Gehrels, the mission's principal investigator.

Question 2

P^2 = 4 pi^2 a^3 / (GM)

P = period of orbit in seconds
a = semimajor axis of orbit in meters
G = the gravitational constant = 6.67428E-11 m^3 kg^-1 sec^-2
M = the sum of the masses of the two objects (e.g., sun and planet), in kilograms.

a=4.62*30.857*10^12=1.425*10^14m

P=479665670.4 sec

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.