Search results
Results From The WOW.Com Content Network
Atomic physics plays a key role in astrophysics as astronomers' only information about a particular object comes through the light that it emits, and this light arises through atomic transitions. Molecular astrophysics , developed into a rigorous field of investigation by theoretical astrochemist Alexander Dalgarno beginning in 1967, concerns ...
This definition goes beyond atoms and molecules, however, to include substances made from these building blocks that are not simply atoms or molecules, for example electron beams in an old cathode ray tube television, or white dwarf matter—typically, carbon and oxygen nuclei in a sea of degenerate electrons. At a microscopic level, the ...
For example, radio astronomy is most sensitive to small linear molecules with a high molecular dipole. [3] The most common molecule in the Universe, H 2 ( molecular hydrogen ), is completely invisible to radio telescopes because it has no dipole; [ 3 ] its electronic transitions are too energetic for optical telescopes, so detection of H 2 ...
Astronomers have detected water molecules on the surface of asteroids for the first time, a surprising find given that the space rocks were thought to be “completely dry.”
For this reason, molecules and molecular ions which are unstable on Earth can be highly abundant in space, for example the H 3 + ion. Astrochemistry overlaps with astrophysics and nuclear physics in characterizing the nuclear reactions which occur in stars, as well as the structure of stellar interiors.
The term outward space existed in a poem from 1842 by the English poet Lady Emmeline Stuart-Wortley called "The Maiden of Moscow", [13] but in astronomy the term outer space found its application for the first time in 1845 by Alexander von Humboldt. [14] The term was eventually popularized through the writings of H. G. Wells after 1901. [15]
Water molecules stay close to each other , due to the collective action of hydrogen bonds between water molecules. These hydrogen bonds are constantly breaking, with new bonds being formed with different water molecules; but at any given time in a sample of liquid water, a large portion of the molecules are held together by such bonds. [61]
Cloud condensation nuclei (CCNs), also known as cloud seeds, are small particles typically 0.2 μm, or one hundredth the size of a cloud droplet. [1] CCNs are a unique subset of aerosols in the atmosphere on which water vapour condenses. This can affect the radiative properties of clouds and the overall atmosphere. [2]