Who was the first Indian astronaut to travel into space?

The flash spectrum confirms a/an:

If the axis of rotation of the earth were extended into space,then it would pass close to

Describe the Ptolemaic model for planetary motion.

If a galaxy is at a distance of $430$ million light years from us,what is the Hubble's constant in $km s^{-1}$ per million light years? Its speed is $6.48 \times 10^6 m s^{-1}$.

Meteors are