What is a hydrogen line?
The
rated line generally refers to the emissions of the radio frequency of the hydrogen in the interstellar space. In our galaxy and other galaxies there is a huge amount of hydrogen. Part of this gas is heated by nearby stars, causing electromagnetic radiation in a visible spectrum - in other words, light. Many of this, however, is far from a source of heat, but it is detectable due to the fact that it releases electromagnetic radiation at a wavelength of 8.3 inches (21.1 centimeters), inside the radio part of the spectrum. This is known as a line of 21 centimeters or a hydrogen line and its existence was predicted by the Dutch astronomer Hendrik van de Hulst in 1944. The lowest energy level is known as the "basic state". Electrons can absorb energy and cause them to "jump" to a higher energy level but earlierFive to a lower level and finally to the basic state, with a time that is inversely proportional to the amount of excess energy. When the electron drops to the level, additional energy is released as an electromagnetic radiation with a frequency that corresponds to the energy difference between the two levels.
The frequency of electromagnetic radiation is proportional to its energy: the greater the energy, the higher the frequency. This relationship is described by a planck equation: E = HF, where E is energy, F is a frequency and H is a planck constant that is approximately 6.626 * 10
-34 joule -sex. The wavelength can be calculated as the speed of light divided by frequencies. Thus, when the electron drops from higher to lower energy, electromagnetic radiation with a certain, fixed frequency and wavelength, is related, related difference in energy will be emitted. This radiation proves to be narrow lines of the emission spectrum.
each element has a characterStick, unique emission spectrum consisting of a number of lines at specific wavelengths. The hydrogen series contains a number of spectral lines, four of which are in the visible part of the spectrum. One of them, a red line known as H-alpha, is much used in astronomy to detect ionized hydrogen in nebulae. These hydrogen emission lines can be considered a hydrogen line, but the term usually refers to the emissions of the radio produced by the cold hydrogen gas on the wavelength 21 centimeters. It's because of another physical process. However, the same rules on energy, frequency and wavelength are still paid.
electrons and protons have a quantum feature known as a "spin" that can have two possible directions. Since hydrogen atom consists of one proton and one electron, it may have two turns in the same direction or in different directions. In the earlier case, the Atom Atom has a little more energy and eventually drops into a lower energy state by switching the electron by spinning. Extra energy is EMIIt is tuned as electromagnetic radiation and because the difference in energy is small, the radiation has a long wavelength and low frequency: 21 centimeters and 1420.4 MHz. A small energy difference also means that any given hydrogen atom in the same spin will take an average of a very long-a-year-old flight to the opposite spin; In the galaxy, however, there is enough cold hydrogen that at any moment it will emit enough hydrogen atoms of 21 centimeters to be detectable.
21 centimeters were detected in 1951 by Harold Ewen and Edward Purcell. It turned out that it is essential in radio astronomy. Much of our galaxy is hidden from the glance of the big clouds of dust that do not allow the light from the star. However, the radio waves are not prevented from dust clouds, and since there are a large amount of cold hydrogen in the galaxy, it is possible to observe and map the galaxy using radio emissions on the hydrogen line. Radio astronomy, using a hydrogen line, allowed us to determine the size, shape and structureOur galaxy.
The rated line is also of great importance for looking for extra earthly intelligence (SETI). It is very possible that technologically advanced civilization could use this frequency to try to communicate with other civilizations. The frequency was used not only to listen to incoming messages, but also to send them. The Pioneer 10 and 11 spacecraft, designed to carry indefinitely through interstellar, contains plaques depicting hydrogen line, its wavelength, its frequency and physics behind it. It represents a measuring unit that is assumed that the extraterrestrials could understand.