galactic disk

galactic disk

See galaxies; Galaxy.

galactic disk

[gə′lak·tik ′disk]
(astronomy)
The flat distribution of stars and interstellar matter in the spiral arms and plane of the Milky Way Galaxy.
References in periodicals archive ?
They found that the older stars were moving in many different directions with some moving very quickly out from the galactic disk. Younger stars move closely together at much slower speeds out from the disc, although they are faster than the older stars as they rotate around the Galaxy within the disc.
The gravitational tug of the Large Magellanic Cloud, which sits 160,000 light-years away from Earth, is pulling more than a billion suns' worth of gas from its smaller companion and feasting on our galactic disk. The structure, named "Leading Arm," appears to be nearly one to two billion-years-old and connects the dwarf galaxies with the bigger one, as per scientists.
The star, which has 1.5 times the mass and 15 times the radius of our sun, lies in the direction of the constellation Ophiuchus on the north side of the galactic disk, around 4,500 light years from Earth.
Most astronomers have regarded these clouds as material falling into the galactic disk from outside.
Although it is bright, the galaxy sits near the equator of the Milky Way's galactic disk, where the sky is thick with glowing cosmic gas, bright stars, and dark, obscuring dust.
The galaxy bar, spiral arms and even galactic rings are structures that can be interpreted as disturbance to axisymmetric potential of the galactic disk.
P Keenan, "Chemical abundances in the inner 5 kpc of the Galactic disk," Astronomy & Astrophysics, vol.
Nobody had seen the arm segment before because the galactic disk turns out to be slightly warped in the outer reaches, like a Frisbee left too long in the sun.
It is thought that the combined ejecta would have broken through the con fining pressure of interstellar gas in the galaxy and erupted to high altitudes above the galactic disk. The theory does not, however, provide a convincing explanation of why there is not also a fountain extending in the opposite direction from the center.
The newly-constructed three-dimensional map of the Milky Way is the first map that is based on direct distances to thousands of individual objects as distant as the expected boundary of the Galactic disk. The map demonstrates that the Milky Way disk is not flat, it is warped at distances greater than 25,000 light years from the Galactic center.
We find many baby clusters within molecular clouds, fewer middle-age and old age clusters in the Galactic disk, and even fewer massive, old globular clusters in the halo.