Place of the Radcliffe Wave in the Local System

TL;DR

This review synthesizes recent measurements of radial velocities and spatial motions to map the Radcliffe wave in the Local System. The wave appears as a narrow front with a length of about 2.5–2.7 kpc and vertical excursions up to roughly 100–160 pc, traced by molecular clouds, dust, YSOs, masers, OB stars, and young open clusters, though vertical-velocity perturbations have been less extensively characterized. The authors show that the Radcliffe wave is not simply a spiral-density-wave feature, but a coherent vertical disturbance with measurable W, including phase relationships among position and velocity in several tracers. Magnetic-field processes, especially Parker instability, emerge as a plausible formation mechanism, requiring interstellar fields of a few μG and tens of Myr timescales; the Gould Belt’s proximity and alignment further suggest a common origin within local disk dynamics. The work also discusses analogues, solar-system crossings through the wave, and the broader context of Orion Arm twist and large-scale disk perturbations, highlighting the Radcliffe wave’s significance for understanding nearby Galactic structure and star-formation processes.

Abstract

A review of publications devoted to the study of the characteristics of the Radcliffe wave has been given. The advent of mass measurements of radial velocities of stars has recently led to a number of interesting results obtained from the analysis of spatial velocities of stars and open star clusters. An important place in the study has been given to issues related to the clarification of the direct or indirect influence of magnetic fields on the process of formation of the Radcliffe wave. The hypothesis of Parker instability of the galactic magnetic field as one of the reasons for the formation of wave-type inhomogeneities in the galactic disk has been discussed.

Figures (6)

• Figure 1: (a) Distribution of 380 molecular clouds from [13] projected onto the galactic plane $XY$ (gray circles) and 189 clouds from a narrow zone (limited by blue dotted lines) passing at an angle of $-30^\circ$ to the $Y$axis (blue filled circles); (b) distribution of maser sources with measured trigonometric parallaxes, Orion arm masers are shown as dark squares. Two fragments of a four-arm spiral pattern with a twist angle $i=-13^\circ$ of are noted, the red line is a segment of the Perseus arm, the blue line is a segment of the Carina--Sagittarius arm, and the Sun is located at the point with coordinates of $(X,Y)=(8.1,0)$ kpc.
• Figure 2: (a) Vertical coordinates of a sample of molecular clouds as a function of distance $y'$; the periodic bold (red) line reflects the results of spectral analysis, while the dashed (blue) line shows the smoothed average values of the coordinates. (b) Power spectrum of a sample of molecular clouds. The figure is taken from the study of Bobylev et al. [27].
• Figure 3: Distribution map of dust matter from [21] with the condensations of young stellar objects (YSOs) plotted, on which we plotted the position of the Sun (yellow circle), a line with a slope of $25^\circ$ to the $Y$ axis (red line) and the approximate position of the Gould Belt (red circle).
• Figure 4: (a) Vertical coordinates of young OSCs depending on the coordinate $y'$, (b) their power spectrum, (c) vertical velocities of OSC depending on the coordinate $y'$, and (d) their power spectrum. The figure is taken from [43].
• Figure 5: Vertical coordinates of young OSCs (upper panel) and their vertical velocities (lower panel) as a function of coordinate $y'$ that were obtained in [18].