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	NGC 5764 rotation curve (Site not responding. Last check: 2007-10-03)
		The accompanying diagram shows the rotation curve of this galaxy - the velocity measured spectroscopically by the redshift of light from stars and gas orbiting at larger and larger distances from the center level off without observable reduction to the limits of the observations - a so-called flat rotation curve.
		The image is a red-light CCD frame taken by W.C. Keel at the 1.1-meter (42-inch) Hall telescope of Lowell Observatory.
		The rotation curve was measured using the GoldCam CCD spectrometer at the 2.1-meter (84-inch) telescope of Kitt Peak National Observatory.
	www.astr.ua.edu /gifimages/ngc5746.html (220 words)

	Galaxy rotation problem - Wikipedia, the free encyclopedia
		The galaxy rotation problem is the discrepancy between the observed rotation speeds of matter in the disk portions of spiral galaxies and the predictions of Newtonian dynamics considering the luminous mass.
		At the time of the discovery of the discrepancy, it was thought that most of the mass of the galaxy had to be in the galactic bulge, near the center.
		The explanation that requires the least adjustment to the physical laws of the universe is that there is a substantial amount of matter far from the center of the galaxy that is not emitting light in the mass-to-light ratio of the central bulge.
	en.wikipedia.org /wiki/Galaxy_rotation_problem (638 words)

	Rotation curve - Wikipedia, the free encyclopedia
		The rotation curve of a galaxy; that is, the orbital velocity as a function of distance from the centre of the galaxy.
		In astrophysics, the rotation curve of a galaxy is a graph that plots the orbital velocity of the stars or gas in the galaxy on the x-axis against the distance from the center of the galaxy on the y-axis.
		Stars rotate around the center of galaxies at a constant velocity regardless of their distance from the center of the galaxy.
	en.wikipedia.org /wiki/Rotation_curve (369 words)

	What is a rotation curve? (Site not responding. Last check: 2007-10-03)
		Rotation curves of spiral galaxies are the profiles of the rotational velocity plotted as a function of radial distance from the galaxy centre.
		Those parts of the disc over which the rotation velocity is still increasing are generally within the so-called optical disc - that is, they are associated with regions which emit visible light and are generally observed in the ordinary visible spectrum.
		The outer part of the disc where the rotation velocity remains at a fixed maximum value is generally in the so-called radio disc - that is, that part of the disc in which virtually all electromagnetic emissions are at radio wavelengths - too long for the human eye to detect.
	www.shef.ac.uk /~ap1dfr/Home_page_files/Research/Discrete_states/node2.html (192 words)

	Learn more about Galaxy rotation problem in the online encyclopedia. (Site not responding. Last check: 2007-10-03)
		The galaxy rotation problem is the discrepancy between the observed rotation of galaxies and the predictions of current physical theories.
		Basically, if one draws a curve describing the orbital speed of stars as a function of the distance from the center, he or she should obtain curve A in fig.
		Reluctant to change Newton's law as well as Einstein's theory of relativity for galaxies only, scientists simply assumed that the rotation curve was flat because of the presence of a large amount of matter surrounding the visible part of galaxies.
	www.onlineencyclopedia.org /g/ga/galaxy_rotation_problem.html (547 words)

	Modified Newtonian dynamics - Wikipedia, the free encyclopedia
		In simple terms, drawing a curve to describe the velocity of stars as a function of their distance from the center of a galaxy should yield curve A (the dashed line in Figure 1); however, data from telescopes yield curve B (the plain line).
		Reluctant to change Newton's law and Einstein's theory of relativity for galaxies alone, scientists have simply assumed that the rotation curve was flat because of the presence of a large amount of matter outside galaxies.
		Since MOND was inspired by the desire to solve the flat rotation curve problem, it is not a surprise that using the MOND theory with observations reconciled this problem.
	en.wikipedia.org /wiki/Modified_Newtonian_dynamics (2737 words)

	Example: Galaxy Rotation Curve (Site not responding. Last check: 2007-10-03)
		The basic principle is to measure the Doppler shift of the spectral lines at different positions along the slit, hence on both sides of the center of the galaxy.
		The rotation curve is obtained from the two-dimensional "spectral image" seen at the right.
		The final rotation curve is obtained by folding the two sides (approach and receding) around the center.
	astrosun2.astro.cornell.edu /academics/courses/astro201/rotcurve.htm (289 words)

	Consistency with Observed Rotation Curves
		Rotation curves which are truly flat and halo-dominated - such as those from isothermal halo models - are extremely difficult to reconcile with observed tidal tails unless they have a small truncation radius (i.e.
		Instead, galaxies appear to possess a variety of rotation curve shapes, and it has been suggested that rotation curve shape is correlated with luminosity and/or Hubble type of the galaxy (e.g., Persic, Salucci, and Stel 1996; McGaugh and de Blok 1998).
		Galaxies with falling rotation curves have no problem making long tails as shown by the examples in Regions I and II of Figure 5.
	www.cita.utoronto.ca /~dubinski/tt3/node14.html (1408 words)

	Galaxy rotation problem
		The galaxy rotation problem refers to the phenonemon of the discrepancy between the observed rotation speeds of matter in the disk portions of spiral galaxies and the predictions of Newtonian dynamics considering the luminous mass.
		As a result, based on Newton's laws, it would be expected that the average orbital speed of an object in rotation at a given radius would decrease inversely with the square root of the radius of the orbit (the dashed line in Fig.
		Rather, the curves do not decrease in the expected inverse square root relationship but are "flat." That, outside of the central bulge, the speed is nearly a constant function of radius (the solid line Fig.
	www.brainyencyclopedia.com /encyclopedia/g/ga/galaxy_rotation_problem.html (427 words)

	Simplified apparatus for and method of tightening fasteners - Patent 4027530
		In this system, signals of both the torque applied and angular rotation of a fastener are measured during the tightening cycle in order to develop a signal indicative of the gradient of the torque-rotation curve which could be plotted for the fastener being tightened.
		In the tightening region of the curve, extending from point A to point B, which region is indicative of the axial force exerted by the fastener clamping the joint members together, the curve is generally linear, but may be slightly curved.
		Mounted on drive shaft 16 for rotation therewith and preferably within motor 14, is a suitable encoder 24 that cooperates with a proximity detector 26 for developing signals representative of the incremental angular displacement or rotation of the fastener.
	www.freepatentsonline.com /4027530.html (5106 words)

	Rotation Curve and Mass Decomposition for the Edge-on spiral galaxy
		This is added to the rotation curve using an equation similar to that of the stars with a term to account for the contribution of He to the mass in gas:
		One of the major uncertainties in fitting mass models to rotation curves is the uncertainty in the contribution of the stellar disk to the rotation curve.
		Using an arctan model for the rotation curve gives a small correction for beam smearing; however the rotation curve derived for UGC 711 rises too slowly in the inner regions to accommodate a reasonable value for the mass to light ratio and for the addition of the gas component.
	www.cv.nrao.edu /~jhibbard/students/CMendelowitz/caylin.html (2529 words)

	A gravitational diffusion model without dark matter -- Britten 95 (7): 3351 -- Proceedings of the National Academy of ...
		The upper curve on the right is based on calculations of the excess force on a test mass immediately external to a large distributed mass for a diffusion case with a mean free path of 5 kpc, as described in the text.
		The squares are the observed velocities of rotation taken from the study by Albada and Sancisi (5).
		The mass distribution for stars and gas was derived from the curve on figure 4 from the study of Albada and Sancisi (5).
	www.pnas.org /cgi/content/full/95/7/3351 (3832 words)

	RotCurve Background - Dark Matter
		So the rotation curves of spiral galaxies are flat, and we have to invoke unseen dark matter to explain this phenomenon.
		One way is to use its influence on the rotation curve to determine how it is distributed in the galaxy.
		The model assumes that all the mass is in the galaxy disk, and that the disk has a mass-to-light ratio of 2.
	burro.astr.cwru.edu /JavaLab/RotcurveWeb/back_DM.html (664 words)

	Halo
		The inner rotation already defined by the bulge and disk produce rotation and mass in the central 5-10 kpc consistent with the previous results from the literature.
		The rotation curves are now low in the centre due to the reduced bulge and disk scalings.
		The rotation curves were of the wrong shape and changing hl in either direction violated either the rotation curve limits or the source position.
	astro.ph.unimelb.edu.au /~ctrott/thesis/node22.html (1363 words)

	Rotation Curves
		The rotation curve for the galaxy NGC3198 from Begeman 1989
		By the same argument the flat galactic rotation curves seem to suggest that each galaxy is surrounded by significant amounts of dark matter.
		The rotation speed is found not to decrease with increasing distance from the galactic center, implying that the mass distribution of the galaxy cannot be concentrated, like the light distribution.
	astro.berkeley.edu /~mwhite/darkmatter/rotcurve.html (938 words)

	Rotation Curves
		The rotation curve for the galaxy NGC3198 from Begeman 1989
		By the same argument the flat galactic rotation curves seem to suggest that each galaxy is surrounded by significant amounts of dark matter.
		The rotation speed is found not to decrease with increasing distance from the galactic center, implying that the mass distribution of the galaxy cannot be concentrated, like the light distribution.
	astron.berkeley.edu /~mwhite/darkmatter/rotcurve.html (938 words)

	Theoretical Constraints
		The reason for this is simply that the circular velocities of the disk and halo are mismatched, so that there is a decline in the rotation curve at the disk-halo transition.
		The only way such galaxies can produce long tidal tails is if the rotation curve falls at the disk-halo transition, such as the models in the upper right of Figure 5.
		Rotation curves which are solely supported by low concentration halos have potential wells too steep to eject long tidal tails.
	www.cita.utoronto.ca /~dubinski/tt3/node15.html (1446 words)

	[No title] (Site not responding. Last check: 2007-10-03)
		Distance in parsecs from the center of the galaxy to the brightest HII regions plotted as a function of the distance in parsecs to the rotation curve turnover.
		The closed circle or triangle represents the point where the rotation velocity reaches a maximum and the open square represents the point where the slope in the rotation curve changes as it is still rising.
		The closed circles represent the points where the rotation velocity reaches a maximum and the open squares represent the point where the slope in the rotation curve changes as it is still rising.
	www.lowell.edu /users/dah/spatial.html (410 words)

	Modified Newtonian dynamics - Open Encyclopedia (Site not responding. Last check: 2007-10-03)
		Basically, if one draws a curve describing the velocity of stars as a function of the distance from the center, he or she should obtain curve A in fig.
		Reluctant to change Newton's law as well as Einstein's theory of relativity for galaxies only, scientists simply assumed that the rotation curve was flat because of the presence of a large amount of matter outside the galaxies.
		The Milky way itself is spawned with clouds of gas and interstellar dust, and until now it has not been possible to draw a rotation curve for our Galaxy.
	open-encyclopedia.com /Modified_Newtonian_dynamics (2781 words)

	Galaxies and the Universe - Dynamics in Disk Galaxies
		Viewing a differentially rotating disk from outside, the velocity field shows a characteristic symmetric "butterfly" pattern, whose contours may be open or closed depending on the form of the rotation curve.
		Rotation curves of real disk galaxies, once it was possible to measure them to large radii, gave one of the big surprises of modern astronomy.
		A first hint came when the rotation curve of the Milky Way was pieced together from optical, H I, and CO observations (from Burton 1976 Ann.
	www.astr.ua.edu /keel/galaxies/diskdyn.html (1609 words)

	Phys 433/813 Assignment 2 (Site not responding. Last check: 2007-10-03)
		As expected given the mass distribution, the relative contributions of the disk and bulge to the rotation curve vary with radius with the disk contribution increasing with R.
		Firstly, the magnitude of the rotation curve calculated from the IR distribution is much lower than the true rotation curve.
		Secondly, the measured rotation curve at the position of the sun is quite flat (see 2 above) whereas the computed rotation curve based on the IR distribution falls off with R -- not in a Keplerian fashion, but still it is declining.
	www.astro.queensu.ca /~irwin/phy433/assignments/ass2/answer2.html (1184 words)

	FirstOnes.com : FAQ - Mara's Controls
		The Rotation / Translation curve is a gauge that defines the difference between a rotation and a translation.
		The curve is a way that provides a pilot with just a single Joystick to use it for a combination of Rotational and Translational movements, without needing an additional Joystick or Throttle.
		The curve is a hyperbola in which the end bounds (usually infinity) are set at a predetermined rate, which I shall from here out call 'full', indicating full power output of the thrusters, in various combinations.
	www.firstones.com /faq/mara.htm (1752 words)

	Excell Program Circ11.xls
		The shape of the standard "target" rotation curve (v sel = 1) is such that over the first 3 units the speed of the rotation curve increases lineair.
		The result of this rotation curve, compared to v sel = 1, is that the density at r = 4 changes from 1.4 to 1.3.
		The result of this rotation curve, compared to v sel = 1, is that the density at r = 4 changes from 1.4 to 1.23.
	users.telenet.be /nicvroom/circ11.xls.htm (2558 words)

	SRT- Small Radio Telescope (Site not responding. Last check: 2007-10-03)
		The purpose of this experiment is to create a rotational curve for the Milky Way Galaxy using 21-cm spectral lines observed with a small radio telescope.
		The rotational curve will be created by plotting the maximum velocity observed along each line of sight versus the distance of this point from the Galactic center.
		Once the rotation curve for the Galaxy is known, it can be used to find the distances to various objects.
	web.haystack.mit.edu /SRT/rotation.html (1166 words)

	Flat Rotation Curves (Site not responding. Last check: 2007-10-03)
		Most galaxies have rotation curves that show solid body rotation in the very center, following by a slowly rising or constant velocity rotation in the outer parts.
		The rotation curve to the right was obtained using red camera the Double Spectrograph in the 5m Hale Telescope at the Palomar 0bservatory.
		Therefore, a flat rotation curve implies that the mass increases linearly with the radius.
	astrosun.tn.cornell.edu /academics/courses/astro201/rotation_flat.htm (151 words)

	Solutions to HW #5 for Chapters 12 - 14
		As the galaxy continued to form, the gas and dust formed a rotating disk (due to conservation of angular momentum), and stars formed at this point will be in the disk.
		Rotation curve B has a larger velocity at 8kpc, and so a larger mass inside 8 kpc is inferred.
		The rotation curve method tells us the mass based on the gravitational influence of all the mass in the galaxy.
	seti.ssl.berkeley.edu /~korpela/astro10/solns/soln5.html (3610 words)

	Rotation Curves and the Galaxy's Mass (Site not responding. Last check: 2007-10-03)
		The curve marked "Kepler" indicates the behavior that would be expected if the visible matter were all the matter in the galaxy.
		The rotation curves for many other spiral galaxies, and various other kinds of observations, point increasingly to the conclusion that at least 90 percent of the matter in the entire visible Universe cannot be seen except through its gravitational influence.
		Because this rotation curve does not fall off as we would expect from applying Kepler's law to the visible matter, these methods indicate that the visible mass (at all wavelengths, not just optical) in the galaxy may be 10 percent or less of the total mass.
	csep10.phys.utk.edu /ojta/course2/milkyway/structure/mass_tl.html (850 words)

	RADIO ASTRONOMY RESULTS
		Notice how the curve is initially linear, this is due to high dynamic drag causing the inner region of the Galaxy to rotate like a solid body.
		Previous rotation curves that have been measured for the Milky Way and other spiral galaxies show a common trend: They have a solid body rotation out to a small radius of approximately 2 to 4 kpc, followed by an approximately flat, constant velocity out to very large distances.
		It is believed that rotation curves are flat and have such high velocities due to the presence of dark matter.
	www.astro.cf.ac.uk /observatory/radiorotn.html (1504 words)

	Fastener tension control system - Patent 4244245
		In a tension control tightening method according to claim 1, wherein said efficiency factor is the ratio between the area under a theoretical torque rotation curve between first and second rotation points on the theoretical curve, and the area under an actual torque rotation curve between said two rotation points on the actual curve.
		Locating a theoretical curve with respect to the actual torque angle curve is simpler and more accurate than projecting the shape of the actual curve back to final zero load angle and then rotating to a predesignated angle to achieve desired final torque.
		Since the equation for the theoretical curve is known, the determination of one torque point on the curve, permits the determination of the torque at any other point.
	www.freepatentsonline.com /4244245.html (3912 words)

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