Kinematics of Galactic Disk
نویسنده
چکیده
The method of constructing of rotation curve for our galactic disk is developed. Simple physical model shows that the velocity of the Sun around the center of the Galaxy must be less than currently accepted IAU value 220 km/s. Independently obtained result for neutral hydrogen (λ = 21.1 cm) confirms the previous statement. The values of the Sun’s velocity is about 110 km/s. As a consequence, the rotation curve for the disk of our Galaxy is not flat, but it is a decreasing function of the distance from the center of the Galaxy. This conclusion seems to be consistent also with other galaxies.
منابع مشابه
The effect of variation of stellar dispersion velocities by the galactic latitude in interpreting gravitational microlensing observations
Our galaxy is a spiral galaxy and its stars are mostly in a thin disk and rotate around the galactic center. The vertical component of the dispersion velocity of stars is a function of the galactic latitude and decreases with increasing it. In the galactic Besancon model, this dependence is ignored and they just consider the dependence of dispersion velocity on the stellar age. Becanson model i...
متن کاملthe Canis Major stellar over - density as due to the Galactic warp
Proper-motion, star counts and photometric catalog simulations are used to explain the detected stellar over-density in the region of Canis Major, claimed to be the core of a disrupted dwarf galaxy (CMa, Martin et al. 2004, Bellazzini et al. 2004), as due to the Galactic warp and flare in the external disk. We compare the kinematics of CMa M-giant selected sample with surrounding Galactic disk ...
متن کاملProbing the Canis Major stellar over - density as due to the Galactic warp
Proper-motion, star counts and photometric catalog simulations are used to explain the detected stellar over-density in the region of Canis Major, claimed to be the core of a disrupted dwarf galaxy (CMa, Martin et al. 2004, Bellazzini et al. 2004), as due to the Galactic warp and flare in the external disk. We compare the kinematics of CMa M-giant selected sample with surrounding Galactic disk ...
متن کاملDoes the Milky Way have a Maximal Disk?
The Milky Way is often considered to be the best example of a spiral for which the dark matter not only dominates the outer kinematics, but also plays a major dynamical role in the inner galaxy: the Galactic disk is therefore said to be “sub-maximal.” This conclusion is important to the understanding of the evolution of galaxies and the viability of particular dark matter models. The Galactic e...
متن کاملGalactic kinematics with modified Newtonian dynamics
We look for observational signatures that could discriminate between Newtonian and modified Newtonian (MOND) dynamics in the Milky Way, in view of the advent of large astrometric and spectroscopic surveys. Indeed, a typical signature of MOND is an apparent disk of “phantom” dark matter, which is uniquely correlated with the visible disk-density distribution. Due to this phantom dark disk, Newto...
متن کاملProduction of Milky-way Structure by the Magellanic-clouds
Previous attempts at disturbing the galactic disk by the Magellanic Clouds relied on direct tidal forcing. However, by allowing the halo to actively respond rather than remain a rigid contributor to the rotation curve, the Clouds may produce a wake in the halo which then distorts the disk. Recent work reported here suggests that the Magellanic Clouds use this mechanism to produce disk distortio...
متن کامل