We know that nothing can have proper velocities larger than the speed of light in vacuum. But are there any objects in space that get close to it? Any comets, or other objects thrown by gravity or ...
Why do planets rotate and revolve in the universe?
According to the theory (or my understanding of it), the universe is not only expanding, but speeding up. If the galaxies are moving apart, are the solar systems within them also moving apart from ...
Some asteroids and comets are non-spherical. But is the nature of big things and gravity so that large things in the universe are always spherical? What is the biggest astronomical object in terms of ...
I'm not asking about theoretical ball, vs saddle, vs flat surface which is just a metaphor with 2D space. It's hard to say as we see very little of it, and we see them in the past because light ...
I've just watched a movie that made me curious as to whether life has really been discovered on another world such as Europa??