Earth appears ________ from the space.
If seen from the earth, the sun appears to move along a circle called ________ .
Why does our earth appear blue from a distance?
Suppose a rocket ship is receding from the earth at a speed of 2/10th the velocity of light. A light in the rocket ship appears blue to the passengers on the ship. What colour would it appear to an observer on the earth?
To an astronaut in a space -ship, the earth appears :
(a) white (b) red
(c) blue (d) black