Various waves of the electromagnetic spectrum, such as radio waves, infrared radiation, X-rays and gamma rays, have allowed us to look into space and "see" much that is hidden from the naked eye. Unfortunately, even a large part of the universe cannot be seen with the help of electromagnetic waves.
And yet, some phenomena, such as gravitational lensing, orbital velocities, and rotational speeds of galaxies, indicate the presence of mass where we do not see it. In particular, these observations show that dark matter exists and is about 5-6 times larger than the one we see. 0 reply
0 recast
2 reactions
0 reply
0 recast
0 reaction