Astrophysics at the University of Arkansas has made an important step to the solution the mystery of how discrete galaxies, like the Roman Road, preserve the shape of the hand.
Their findings support the theory of creating these weapons wave of dense substance It creates a spiral pattern when it travels through the galaxy.
"The structure of the spiral arms in discrete galaxies is a mystery," said Ryan Miller, assistant professor of physics visiting, "Nobody knows what determines the shape of these spirals, or why they have a certain number of deadlines." clear answer part of this secret. "
The Camelopardalis Galaxy, also known as the hidden galaxy, has a spiral shape. (Archive)
Discolored galaxies, including the Roman road, comprise 70% of the known galaxies. They are characterized by spiral arms, but astronomers are not sure how they are designed and maintained.
The secret begins with a simple paradox: the stars in the discrete galaxy circle along a central mass called the "galactic bulge", and the stars move closer to the central orbit faster than the stars toward the edge. But if the spiral arms were made up of a fixed group of stars, those at the edges of the sample should cover a greater distance than the stars in the middle to make the pattern spiral. As running in the outer track of the circular track, we should move faster in order to maintain our position in the group.
In the 1960s, astronomers proposed a "wave density theory" to explain this paradox. The theory is that the hands of discrete galaxies are not formed from static bundles of stars. Instead, these hands are waves of denser areas that move through the stars. The stars move in accordance with physical laws and, they circulate along the center of the galaxy, they encounter this more dense area.
Many astronomers have compared the wave of denser substances with traffic jam in which the velocity of a star traveling in a circle around the center of the galaxy affects the denser substance in the same way as the motor vehicles that are under the influence of the congested part of the highway. They slow down when they encounter congestion and are able to move more easily after overcoming a traffic jam.
The most frequent areas also affect gas clouds flowing through these regions. Squeezed and crash into new stars.
Miller and his colleagues supported wavelength theory by observing stars of different ages and comparing their locations with a center in the center of the wave of density.
According to theory, there would be a point in each branch of the galaxy where the speed of the wavelengths of the waves and the velocity of the stars are the same. This is called radium rotation. The stars in the radius of rotation must move faster than the density wave because they are closer to the center. So, the older star becomes, you must continue to travel from your home town near the wave. On the outer side of the radial wheel, where the stars travel slower than the density of the density, the older stars would have to fall behind the wave.
The researchers reviewed the galaxy images of the NASA / IPAC Extragalactic Database, run by NASA's Jet Propulsion Laboratory at the California Institute of Technology. For each galaxy, images of different wavelengths of light representing stars of different ages were examined. They found that each group of stars formed a hand with a slightly different "angle of inclination", which is like arms relative to the center of the galaxy. When comparing these different angles with the angle formed by the center of the density waves, it was shown that the position of these star groups coincides with the forecast of the theory of the density of the waves.
Although research proves why spiral arms retain their form, questions are continuing. It is understandable why a traffic jam occurs when a traffic accident occurs, which reduces the three lanes to one, but determining what creates the worst waves remains an open question.