Astronomy | Astrophysics Answers

what are dark matters and dark energy?

Express the distance of the star proxima centauri from the star sirius B and the planet Earth in light years.

1)which telescope, optical or X-ray, would have higher resolving power for the same aperture?
2)A supernova explosion takes place at the distance of 4 pc. If the absolute magnitude of the supernova is -25, calculate It's apparent magnitude. Will the supernova be brighter than the sun, justify the answer.

A spaceship moving with an initial velocity of 58.0 meters/second experiences a uniform acceleration and attains a final velocity of 153 meters/second. What distance has the spaceship covered after 12.0 seconds?

1. a) Express the distance of the star Proxima Centauri from the star Sirius B and the planet
Earth in light years.

1. d) The average temperature of the interior of a sun-like star is of the order 10^8 K. Estimate
the mass of the star in terms of the solar mass if it has a radius of order 10^10 cm.

3. b) A supernova explosion takes place at the distance of 4 pc. If the absolute magnitude of
the supernova is −25, calculate its apparent magnitude. Will the supernova be brighter
than the Sun? Justify your answer.

2. b) If the pressure in the solar atmosphere is 10^4 Pa, calculate the strength of the magnetic
field required to balance it (pressure).

1. d) The average temperature of the interior of a sun-like star is of the order 10^8 K. Estimate
the mass of the star in terms of the solar mass if it has a radius of order 10^10 cm.

Draw the celestial sphere and show the observer’s meridian, zenith, celestial equator and the horizon for an observer at latitude 30°N. Show the horizon coordinates of a star X on the celestial sphere for this observer. Would these coordinates be the same at latitude 60° N?

The average temperature of the interior of a sun-like star is of the order 108 K. Estimate the mass of the star in terms of the solar mass if it has a radius of order 1010 cm.