Cosmic noise characteristics are similar to those of thermal noise. Cosmic noise is experienced at frequencies above about 15 MHz when highly directional antennas are pointed toward the sun or to certain other regions of the sky such as the center of the Milky Way Galaxy. Celestial objects like Quasars, super dense objects that lie far from Earth, emit electromagnetic waves in its full spectrum including radio waves. We can also hear the fall of a meteorite in a radio receiver; the falling object burns from friction with the Earth’s atmosphere, ionizing surrounding gases and producing radio waves. Cosmic Microwave Background Radiation (CMBR) from outer space, discovered by Arno Penzias and Robert Wilson, who later won the Nobel Prize for this discovery, is also a form of cosmic noise. CMBR is thought to be a relic of the Big Bang, and pervades the space almost homogeneously over the entire celestial sphere. The bandwidth of the CMBR is wide, though the peak is in the microwave range.
A binary black hole (BBH) is a system consisting of two black holes in close orbit around each other. Like black holes themselves, binary black holes are often divided into stellar binary black holes, formed either as remnants of high-mass binary star systems or by dynamic processes and mutual capture, and binary supermassive black holes believed to be a result of galactic mergers.
Time travel — moving between different points in time — has been a popular topic for science fiction for decades. Franchises ranging from “Doctor Who” to “Star Trek” to “Back to the Future” have seen humans get in a vehicle of some sort and arrive in the past or future, ready to take on new adventures.The reality, however, is more muddled. Not all scientists believe that time travel is possible. Some even say that an attempt would be fatal to any human who chooses to undertake it.