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Sound of the universe

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.

Sounds from different nebulae.

Sounds from different comets

Sounds of the Sun

Sounds of the Eskimo nebula NGC2392.

Sounds of a quasar

Kepler’s laws of planetary motion

In astronomy, Kepler’s laws of planetary motion are three scientific laws describing the motion of planets around the Sun. Kepler’s laws are now traditionally enumerated in this way:


Figure 1: Illustration of Kepler’s three laws with two planetary orbits.
(1) The orbits are ellipses, with focal points ƒ1 and ƒ2for the first planet and ƒ1 and ƒ3 for the second planet. The Sun is placed in focal point ƒ1.

(2) The two shaded sectors A1 and A2 have the same surface area and the time for planet 1 to cover segment A1 is equal to the time to cover segment A2.

(3) The total orbit times for planet 1 and planet 2 have a ratio a13/2 : a23/2.

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Black hole thermodynamics

In physics, black hole thermodynamics is the area of study that seeks to reconcile the laws of thermodynamics with the existence of black hole event horizons. Much as the study of the statistical mechanics of black body radiation led to the advent of the theory of quantum mechanics, the effort to understand the statistical mechanics of black holes has had a deep impact upon the understanding of quantum gravity, leading to the formulation of the holographic principle.

An artist depiction of two black holes merging, a process in which the laws of thermodynamicsare upheld.

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