Astronomy | Astrophysics Answers

1d) The latitude and longitude (in degrees) of Mumbai and Shillong are as follows:

Mumbai: latitude 19 N longitude 73 E

Shillong: latitude 26 N longitude 92 E.

When it is 12:00 O’clock local time at Shillong, what is the local time in Mumbai?

1c) Sketch the celestial equator, horizon, observer’s meridian and show the zenith and

nadir on the celestial sphere for an observer at latitude 30 N.

1b) What is meant by the apparent magnitude of a star? How is it related to the

brightness of the star? An object A has an apparent magnitude of –5. Another

object B has an apparent magnitude of –10. Calculate the ratio of their brightness.

1. a) Express the distances of the stars Sirius A and Antares from the Earth in light years. 

What is big bang

1. Imagine you were carrying your lunch to a table at a constant and slow speed when all of the sudden you need to quickly change direction. What will happen to the lunch on your plate if you aren’t careful? 

 Consider a spherical galaxy in which the velocity distribution is such that their directions are uniformly distributed in all directions. If we make the assumption that the magnitude of the velocities are equal and have a value of vs. The distance to the galaxy is D and the Hubble constant is H0. The emmision line of a certain element is observed whose wavelength as measured a laboratory setup is λ0. Calculate the line profile of this emission line from the galaxy. 

Radio telescopes are an essential tool for modern astrophysics. They played a crucial role in

discovering a fascinating astronomical object: Pulsars - highly compact objects that periodically

emit radiation. Pulsars are still an active part of astrophysical research.

Explain how pulsars are formed and the causes for their pulsating behaviour.

A research team has discovered that a moon is circling a planet of our solar system: The moon

orbits the planet once every 7 hours on a nearly circular orbit in a distance R of 48000 km from

the centre of the planet. Unfortunately, the mass m of the moon is not known. Use Newton’s law

of gravitation with G = 6.67 · 10−11 m3

/(kg·s

2

) to approach the following questions:

F = G ·

mM

R2

(a) Based on the observations, determine the total mass M of the planet.

(b) Which moon and planet of our solar system is the team observing? (Use literature.)

Solve both and explain them properly ...

a) Using the data on Mars' moon Phobos, (its mass and distance from the planet) determine using the general form of Kepler’s Third Law (a la Newton) the mass of Mars. 

b) List in point form information about Venus, Earth and Mars. Compare and contrast their characteristics from the perspective of the habitability for life both past and present on these planets.