Bow Shock Model Research Articles

Multispacecraft observations of the terrestrial bow shock and magnetopause during extreme solar wind disturbances

Abstract. Three events are discussed from the declining phase of the last solar cycle when the magnetopause and/or the bow shock were observed unusually close to the Earth due to major interplanetary disturbances. The observed extreme locations of the discontinuities are compared with the predictions of three magnetopause and four bow shock models which describe them in considerably different ways using statistical methods based on observations. A new 2-D magnetopause model is introduced (based on Verigin et al., 2009) which takes into account the pressure of the compressed magnetosheath field raised by the interplanetary magnetic field (IMF) component transverse to the solar wind flow. The observed magnetopause crossings could be predicted with a reasonable accuracy (0.1–0.2 RE) by one of the presented models at least. For geosynchronous magnetopause crossings observed by the GOES satellites, (1) the new model provided the best predictions when the IMF was extremely large having a large negative Bz component, and (2) the predictions of the model of Shue et al. (1998) agreed best with the observations when the solar wind dynamic pressure was extremely large. The magnetopause crossings close to the cusp observed by the Cluster spacecraft were best predicted by the 3-D model of Lin et al. (2010). The applied empirical bow shock models and the 3-D semi-empiric bow shock model combined with magnetohydrodynamic (MHD) solution proved to be insufficient for predicting the observed unusual bow shock locations during large interplanetary disturbances. The results of a global 3-D MHD model were in good agreement with the Cluster observations on 17 January 2005, but they did not predict the bow shock crossings on 31 October 2003.

The planetesimal bow shock model for chondrule formation: A more quantitative assessment of the standard (fixed Jupiter) case

Abstract– One transient heating mechanism that can potentially explain the formation of most meteoritic chondrules 1–3 Myr after CAIs is shock waves produced by planetary embryos perturbed into eccentric orbits via resonances with Jupiter following its formation. The mechanism includes both bow shocks upstream of resonant bodies and impact vapor plume shocks produced by high‐velocity collisions of the embryos with small nonresonant planetesimals. Here, we investigate the efficiency of both shock processes using an improved planetesimal accretion and orbital evolution code together with previous simulations of vapor plume expansion in the nebula. Only the standard version of the model (with Jupiter assumed to have its present semimajor axis and eccentricity) is considered. After several hundred thousand years of integration time, about 4–5% of remaining embryos have eccentricities greater than about 0.33 and shock velocities at 3 AU exceeding 6 km s−1, currently considered to be a minimum for melting submillimeter‐sized silicate precursors in bow shocks. Most embryos perturbed into highly eccentric orbits are relatively large—half as large as the Moon or larger. Bodies of this size could yield chondrule‐cooling rates during bow shock passage compatible with furnace experiment results. The cumulative area of the midplane that would be traversed by highly eccentric embryos and their associated bow shocks over a period of 1–2 Myr is <1% of the total area. However, future simulations that consider a radially migrating Jupiter and alternate initial distributions of the planetesimal swarm may yield higher efficiencies.

Predictive model of magnetosheath plasma flow and its validation against Cluster and THEMIS data

Abstract. An analytical model of magnetosheath plasma flow is described and compared with a large dataset of magnetosheath ion flow velocity measurements from Cluster and THEMIS spacecraft. The model is based on previous works by Kobel and Flückiger (1994) and Génot et al. (2011) and has been modified to overcome the restrictions of these models on the shape of model magnetopause and bow shock. Our model is compatible with any parabolic bow shock model and arbitrary magnetopause model. The model is relatively simple to implement and computationally inexpensive, and its only inputs are upstream solar wind parameters. Comparison with observed data yields a good correspondence: median error in the direction of flow velocity is comparable with the instrumental error, and flow magnitude is predicted with a reasonable accuracy (relative error in flow speed was less than 25% for 86.5% of observations).

THE EXTREMELY HIGH VELOCITY OUTFLOW FROM THE LUMINOUS YOUNG STELLAR OBJECT G5.89–0.39

We have imaged the extremely high-velocity outflowing gas in CO (2-1) and (3-2) associated with the shell-like ultracompact HII region G5.89-0.39 at a resolution of ~3" (corresponding to ~4000 AU) with the Submillimeter Array. The integrated high-velocity (>45 km/s) CO emission reveals at least three blueshifted lobes and two redshifted lobes. These lobes belong to two outflows, one oriented N-S, the other NW-SE. The NW-SE outflow is likely identical to the previously detected Br_gamma outflow. Furthermore, these outflow lobes all clearly show a Hubble-like kinematic structure. For the first time, we estimate the temperature of the outflowing gas as a function of velocity with the large velocity gradient calculations. Our results reveal a clear increasing trend of temperature with gas velocity. The observational features of the extremely high-velocity gas associated with G5.89-0.39 qualitatively favor the jet-driven bow shock model.

A new semiempirical model of Saturn's bow shock based on propagated solar wind parameters

[1] A new semiempirical model of Saturn’s dayside bow shock is presented. The model uses observations made during the Pioneer 11, Voyager 1, and Voyager 2 flybys as well as data from the first 6 years of the Cassini mission (2004–2010) to derive the average shape of the shock surface and the variation of shock subsolar distance with solar wind dynamic pressure. The 574 bow shock crossings used to construct the model provide good local time coverage of the dayside shock surface up to latitudes of roughly 45°, allowing the three‐dimensional shape of the shock surface to be investigated for the first time. Narrowband Langmuir waves observed by the Radio and Plasma Wave Science instrument are combined with propagated solar wind velocities in order to estimate the solar wind dynamic pressure associated with each of the Cassini crossings. An axisymmetric second‐order surface is then fit to the resulting crossing distribution, self‐consistently accounting for solar wind dynamic pressure variations. The new semiempirical model is compared with existing models of Saturn’s bow shock and magnetopause, and the physical implications of the model are discussed. On the basis of these comparisons, it is proposed that the new semiempirical model is the most accurate representation of Saturn’s bow shock surface to date.

The circumstellar environment of the YSO TMR-1 and a revisit to the candidate very low-mass object TMR-1C

TMR-1 (IRAS~04361+2547) is a class~I proto-stellar source located in the nearby Taurus star-forming region. Its circumstellar environment is characterized by extended dust emission with complex structures and conspicuous filaments. A faint companion, called TMR-1C, located near the proto-star had been detected in previous studies, but its nature as a very young substellar object remained inconclusive. To improve the constraints on the nature of TMR-1C, and to investigate the process of very low-mass star formation in the TMR-1 system we use very sensitive infrared imaging observations as well as NIR spectroscopy. We construct the SED of TMR-1C over a much larger wavelength range as had been possible in previous work and compare it with models of extincted background stars, young sub-stellar objects, and very low-mass stars with circumstellar disk and envelope emission. We also search for additional low-luminosity objects in the immediate environment of the TMR-1, study the surrounding NIR dust morphology, and analyse the emission line spectrum of a filamentary structure in the physical context of a bow-shock model. We find that the observed SED of TMR-1C is inconsistent with an extincted background star, nor can be fitted with available models for a young extremely low-mass (<12M_Jup) object. Our near-IR spectrum indicates an effective temperature of at least ~3000K. Based on a good match of TMR-1C's SED with radiation transfer models of young stellar objects with circumstellar disks, we propose that TMR-1C is most likely a very low-mass star with M~0.1-0.2M_sun surrounded by a circumstellar disk with high inclination, i>80deg. Moreover, we detect an additional very faint source, which we call TMR-1D, and that shows a quite striking symmetry in position with TMR-1C. TMR-1C and TMR-1D may have been formed from a common triggered star-formation event, caused by... (abstract abridged)

Comet-shaped sources at the Galactic center

<i>Context. <i/>In 2007 we reported two comet-shaped sources in the vicinity of Sgr A* (0.8” and 3.4” projected distance), named X7 and X3. The symmetry axes of the two sources are aligned to within 5° in the plane of the sky, and the tips of their bow shocks point towards Sgr A*. Our measurements show that the proper motion vectors of both features are pointing in directions more than 45° away from the line that connects them with Sgr A*. This misalignment of the bow-shock symmetry axes and their proper motion vectors, combined with the high proper motion velocities of several 100 km s<sup>-1<sup/>, suggest that the bow shocks must be produced by an interaction with some external fast wind, possibly coming from Sgr A*, or from stars in its vicinity.<i>Aims. <i/>We have developed a bow-shock model to fit the observed morphology and constrain the source of the external wind. <i>Methods. <i/>The result of our modeling gives the best solution for bow-shock standoff distances for the two features, which allows us to estimate the velocity of the external wind, making certain that all likely stellar types of the bow-shock stars are considered.<i>Results. <i/>We show that neither of the two bow shocks (one of which is clearly associated with a stellar source) can be produced by the influence of a stellar wind of a single mass-losing star in the central parsec. Instead, an outflow carrying a momentum comparable to the one contributed by the ensemble of the massive young stars can drive shock velocities capable of producing the observed comet-shaped features. We argue that a collimated outflow arising perpendicular to the plane of the clockwise rotating stars (CWS) can easily account for the two features and the mini-cavity. However, the collective wind from the CWS has a scale of <i>><i/>10”. The presence of a strong, mass-loaded outbound wind at projected distances from Sgr A* of <i><<i/>1” in fact agrees with models that predict a highly inefficient accretion onto the central black hole owing to a strongly radius dependent accretion flow.

Venusian bow shock as seen by the ASPERA‐4 ion instrument on Venus Express

The Analyzer of Space Plasmas and Energetic Atoms (ASPERA‐4) instrument on Venus Express is used to determine bow shock position at Venus using ion data alone, using data recorded during a solar minimum from the Ion Mass Analyzer (IMA) which is part of the ASPERA‐4 package. Previous models constructed from solar minimum data using Venus Express, Pioneer Venus Orbiter (PVO) and Venera 9 and 10 are also compared to the current fit. An important feature of this new fit is a statistical accuracy introduced in the form of a probability weighting function for the data points, based on the time spent in particular locations. The bow shock curve is then compared to two‐dimensional ion maps. These verify the accuracy of this and previous solar minimum fit curves based on PVO and Venus Express magnetic data. Comparing all bow shock models to the 2D ion maps shows that a combination of models produces the best fit. Since all the fitted curves show differences in position they are investigated relative to the solar conditions pertaining at the times when the individual data sets were measured. The sub solar point and terminator distance were thus found to vary linearly with sunspot number and hence with solar activity. This relationship, which was already known to exist between solar maximum and solar minimum, is now shown to exist between different solar minima and even within the same minimum. This indicates a need for the mechanisms for bow shock maintenance and variance to be more closely modeled.

Observations of loss cone-shaped back streaming energetic protons upstream of the Earth's bow shock

[1] Energetic ions are at times observed in the upstream region of the Earth's bow shock, and their origin is considered to be in the interaction with the shock front. While the energy of the solar wind ions is a few keV at most, the energy of the back streaming ions ranges from ∼5 keV to several MeV. In the present study we investigate back streaming energetic ions in the upstream of the Earth's bow shock observed by Geotail during two coronal mass ejection events. The observed local magnetic field rotated significantly during the events. Using the bow shock model and the observed magnetic field data, we found that the energetic ions appeared only when the upstream magnetic field was connected to the bow shock. The energetic ions showed two distinct distribution function characteristics, namely, the field-aligned beam (FAB) and the loss cone―shaped distribution. While the former is occasionally detected, the latter having higher energies (30 keV to several hundred keV, compared to <18 keV for FAB) has not been reported before. Using a bow shock model, we can also estimate the shock angle at the point on the shock surface that the upstream field line is connected to and find that the distribution function shape transits from the FAB to the loss cone―shaped distribution as the shock angle becomes larger (transition at Θ Bn = 70°―80°). We discuss the possible mechanisms responsible for the production of the newly found member of the energetic upstream ion family.

FUSEOBSERVATIONS REVEAL THE NATURE OF THE STELLAR JETS IN R Aqr

R Aquarii is a symbiotic system consisting of a Mira variable and a white dwarf companion. Its jet-like structures have been observed in the X-rays through the radio and extend up to 2500 AU from the central object. We report Far Ultraviolet Spectroscopic Explorer observations of O VI emission from these stellar jets that reveal signature line profiles of bow shocks. We have calculated bow shock models for a fully radiative shock, fully non-radiative shock, and a new hybrid set of models. We found that fully non-radiative shocks do not produce good fits to the data. While a fully radiative bow shock model cannot be excluded, the high densities required led us to develop hybrid bow shock models in which the shock is non-radiative near the apex of the bow shock, but becomes radiative at some distance from the apex. The model that best fits the data is the hybrid bow shock with a shock speed of approximately 235-285 km s–1 and an inclination angle of ~ +10° and +35° with the plane of the sky for the northeast and the southwest jets, respectively. A turbulent velocity of about 60 km s–1 was required to obtain good fits. Surprisingly, both of the opposing jets have similar model parameters in spite of their very different O VI flux and distance from the central object. This analysis confirms the ejecta bow shock scenario as opposed to the cloudlet bow shock, constraining the mechanism of jet production to characteristics of the central object. The striking similarities in the physical parameters of the jets indicate a common origin and support the precessing accretion disk scenario for the white dwarf in the R Aqr system. For both jets we find pre-shock densities in the range of 103-104 cm–3 at positions of the brightest X-ray emission from the jets, which are also the positions of the apparent outer terminal points of the jets, providing strong support for the theory that the emission and shock structures we are seeing are produced when the jet material interacts with an external nebular wall.

CO emission and variable CH and CH+absorption towards HD 34078: evidence for a nascent bow shock?

The runaway star HD34078, initially selected to investigate small scale structure in a foreground diffuse cloud has been shown to be surrounded by highly excited H2. We first search for an association between the foreground cloud and HD34078. Second, we extend previous investigations of temporal absorption line variations (CH, CH+, H2) in order to better characterize them. We have mapped the CO(2-1) emission at 12 arcsec resolution around HD34078's position, using the 30 m IRAM antenna. The follow-up of CH and CH+ absorption lines has been extended over 5 more years. In parallel, CH absorption towards the reddened star Zeta Per have been monitored to check the homogeneity of our measurements. Three more FUSE spectra have been obtained to search for N(H2) variations. CO observations show a pronounced maximum near HD34078's position, clearly indicating that the star and diffuse cloud are associated. The optical spectra confirm the reality of strong, rapid and correlated CH and CH+ fluctuations. On the other hand, N(H2, J=0) has varied by less than 5 % over 4 years. We also discard N(CH) variations towards Zeta Per at scales less than 20 AU. Observational constraints from this work and from 24 micron dust emission appear to be consistent with H2 excitation but inconsistent with steady-state bow shock models and rather suggest that the shell of compressed gas surrounding HD34078, is seen at an early stage of the interaction. The CH and CH+ time variations as well as their large abundances are likely due to chemical structure in the shocked gas layer located at the stellar wind/ambient cloud interface. Finally, the lack of variations for both N(H2, J=0) towards HD34078 and N(CH) towards Zeta Per suggests that quiescent molecular gas is not subject to pronounced small-scale structure.

ATOMIC JETS FROM CLASS 0 SOURCES DETECTED BYSPITZER: THE CASE OF L1448-C

We present Spitzer-IRS spectra obtained along the molecular jet from the Class 0 source L1448-C (or L1448-mm). Atomic lines from the fundamental transitions of [FeII], [SiII] and [SI] have been detected showing, for the first time, the presence of an embedded atomic jet at low excitation. Pure rotational H$_2$ lines are also detected, and a decrease of the atomic/molecular emission ratio is observed within 1 arcmin from the driving source. Additional ground based spectra (UKIRT/UIST) were obtained to further constrain the H$_2$ excitation along the jet axis and, combined with the 0--0 lines, have been compared with bow-shock models. From the different line ratios, we find that the atomic gas is characterized by an electron density n_e ~ 200-1000 cm^{-3}, a temperature T_e < 2500 K and an ionization fraction <~ 10^{-2}; the excitation conditions of the atomic jet are thus very different from those found in more evolved Class I and Class II jets. We also infer that only a fraction (0.05-0.2) of Fe and Si is in gaseous form, indicating that dust still plays a major role in the depletion of refractory elements. A comparison with the SiO abundance recently derived in the jet from an analysis of several SiO sub-mm transitions, shows that the Si/SiO abundance ratio is ~100, and thus that most of the silicon released from grains by sputtering and grain-grain collisions remains in atomic form. Finally, estimates of the atomic and molecular mass flux rates have been derived: values of the order of ~10$^{-6}$ and ~10$^{-7}$ M$_{\sun}$ yr$^{-1}$ are inferred from the [SI]25$\mu$m and H$_2$ line luminosities, respectively. A comparison with the momentum flux of the CO molecular outflow suggests that the detected atomic jet has the power to drive the large scale outflow.

An empirical model of Saturn's bow shock: Cassini observations of shock location and shape

We present a new empirical model of Saturn's bow shock that utilizes observations from the Cassini spacecraft. Shock crossings are identified in magnetic field and plasma observations made by Cassini between June 2004 and August 2005. The Cassini crossings are then combined with the crossings made during the Saturn flybys of Pioneer 11, Voyager 1, and Voyager 2. Solar wind dynamic pressures for the Cassini crossings are estimated using upstream electron densities determined from Langmuir wave observations made by the Radio and Plasma Wave System. The crossing positions are rotated into aberrated coordinates to correct for the effect of the planet's orbital motion. In the case of Saturn this rotation is by ∼1°. To correct for solar wind dynamic pressure variations, the crossing positions are normalized to the average pressure 〈PSW〉 = 0.048 nPa. The model is then obtained by fitting a conic section to the crossings using a nonlinear least squares technique. To validate the assumptions made in constructing the model, we treat the parameters previously assumed to be constants as variables and fit their values using an optimization routine; this leads to a conic section that is within the positional uncertainty of the model. The spacecraft trajectories are considered, and we conclude that they do not significantly bias the model. The new model is compared to the existing models, and the similarities and differences are discussed. We suggest that the new model gives the most accurate empirical representation of the shape and location of Saturn's bow shock.

Influence of the tilt angle on the bow shock shape and location

The bow shock is created in front of an obstacle immersed into a supersonic flow and its location depends on the size and shape of the obstacle. It was found that the obstacle (magnetopause) is scaled with the solar wind dynamic pressure and changes its dimensions and shape with the dipole tilt angle and interplanetary magnetic field orientation. Similar functional dependencies would be expected for the bow shock position, however, none of the bow shock models considers the parametrization of bow shock properties with the tilt angle. The present study employs a set of bow shock crossings registered during 1994–2002 by different spacecraft and demonstrates the tilt angle influence on the bow shock location. The study is based on a comparison of a recent bow shock model with observations and shows that the night–side bow shock moves in the direction of the positive ZGSM axis for positive tilt angles. The magnitude of the displacement can reach ≈3 RE. The analysis reveals that the high–latitude bow shock surface is significantly distorted near the dawn–dusk meridian. This effect was identified as a counterpart of the magnetopause indentation in the cusp region.

Initial Venus Express magnetic field observations of the Venus bow shock location at solar minimum

In this study, magnetic field measurements obtained by the Venus Express spacecraft are used to determine the bow shock position at solar minimum. The best fit of bow shock location from solar zenith angle 20–120° gives a terminator bow shock location of 2.14 R V (1 R V=6052 km) which is 1600 km closer to Venus than the 2.40 R V determined during solar maximum conditions, a clear indication of the solar cycle variation of the Venus bow shock location. The best fit to the subsolar bow shock is 1.32 R V, with the bow shock completely detached. Finally, a global bow shock model at solar minimum is constructed based on our best-fit empirical bow shock in the sunlit hemisphere and an asymptotic limit of the distant bow shock which is a Mach cone under typical Mach number of 5.5 at solar minimum. We also describe our approach to making the measurements and processing the data in a challenging magnetic cleanliness environment. An initial evaluation of the accuracy of measurements shows that the data are of a quality comparable to magnetic field measurements made onboard magnetically clean spacecraft.

VLA and Effelsberg observations of the interstellar medium around the runaway star WR 124

Aims. We present very large array (VLA) and Effelsberg radio continuum and 21 cm H i line observations of the interstellar medium (ISM) surrounding the runaway star WR 124 and the nebula M 1-67. The H I data have been used to investigate the effects that a star with a strong stellar wind and a high peculiar velocity has on the ISM. Methods. The VLA 21 cm H I observations were combined with single-dish Effelsberg observations to produce a series of H I images sensitive to all angular scales from the VLA resolution limit (∼46 �� ) up to the primary field of individual VLA antennae (FWHM = 36 � ). MSX and IRIS images were used to analyze the infrared emission around the star. Because the star is highly supersonic with respect to its local ISM, the observed H I distribution around the star is interpreted in terms of a simple bow shock model. Results. The analysis of the H I data reveals the presence of a cavity centered on the star at an LSR velocity of ∼60 km s −1 , consistent with a distance estimate of 5 kpc for WR 124. A second H I cavity is observed located 10 � to the north of the stellar position, consistent with the direction of motion of WR 124. The VLA continuum image at 8.5 GHz shows a remarkable resemblance to the optical images. All available radio continuum data suggest a purely thermal spectrum for the nebula. The MSX and IRIS infrared data show a changing morphology with wavelength. The dust temperature deduced from the infrared luminosities is in agreement with previous observations of bow shocks.

Small-scale deformation of the bow shock

The prediction of the bow shock location is a proof of our understanding of the processes governing the solar wind – magnetosphere interaction. However, the models describing the bow shock location as a function of upstream parameters are based on a statistical processing of bow shock crossings observed by a single spacecraft. Such crossings locate the bow shock in motion, i.e., in a non-equilibrium state and this fact can be a source of significant errors. We have carefully analyzed a long interval of simultaneous observations of the bow shock and magnetopause and another interval of bow shock observations at two well-separated points. Our results suggest that often a small-scale deformation of the bow shock front due to magnetosheath fluctuations is the most appropriate interpretation of observations. Since the low-frequency magnetosheath variations exhibit largest amplitudes, a simultaneous bow shock displacement over a distance of 10–15 R E can be observed. We suggest that bow shock models can be probably improved if the tilt angle would be implemented as a parameter influencing the bow shock location in high latitudes.

Shock excitation of the knots of Hen 3-1475

We present new optical STIS HST spectroscopic observations of the jets of the proto-planetary nebula Hen 3-1475. The excitation conditions of the knots of Hen 3-1475 are derived from the observed optical spectra, confirming that the knots are shock excited. The shocked spectra are qualitatively reproduced by simple ``3/2''D bow shock models. We present a set of bow shock models devoted to planetary nebulae, and discuss the effects of the pre-ionization conditions, the bow shock velocity, the bow shock shape and the chemical abundances on the predicted spectra. To explore the reliability of the ``3/2''D bow shock models, we also compare the observed spectra of other three proto-planetary nebulae (M 1-92, M 2-56 and CRL 618) to the predicted spectra.

Hydrodynamics of Cometary Compact H ii Regions

We present numerical radiation-hydrodynamic simulations of cometary H II regions for a number of champagne flow and bow shock models. For the champagne flow models we study smooth density distributions with both steep and shallow gradients. We also consider cases in which the ionizing star has a strong stellar wind and cases in which the star additionally has a proper motion within the ambient density gradient. We find that our champagne flow plus stellar wind models have limb-brightened morphologies and kinematics that can see the line-of-sight velocities change sign twice between the head and tail of the cometary H II region, with respect to the rest frame velocity. Our bow shock models show that pressure gradients across and within the shell are very important for the dynamics and that simple analytic models assuming thin shells in ram pressure balance are wholly inadequate for describing the shape and kinematics of these objects at early times in their evolution. The dynamics of the gas behind the shock in the neutral material ahead of the ionization front in both champagne flow and bow shock type cometary H II regions is also discussed. We present simulated emission-measure maps and long-slit spectra of our results. Our numerical models are not tailored to any particular object, but comparison with observations from the literature shows that, in particular, the models combining density gradients and stellar winds are able to account for both the morphology and general radial velocity behavior of several observed cometary H II regions, such as the well-studied object G29.96-0.02.

Infall and Outflow around the HH 212 Protostellar System

HH 212 is a highly collimated jet discovered in H2 powered by a young Class 0 source, IRAS 05413-0104, in the L1630 cloud of Orion. We have mapped around it in 1.33 mm continuum, 12CO ($J=2-1$), 13CO ($J=2-1$), C18O ($J=2-1$), and SO ($J_K = 6_5-5_4$) emission at $\sim$ \arcs{2.5} resolution with the Submillimeter Array. A dust core is seen in the continuum around the source. A flattened envelope is seen in C18O around the source in the equator perpendicular to the jet axis, with its inner part seen in 13CO. The structure and kinematics of the envelope can be roughly reproduced by a simple edge-on disk model with both infall and rotation. In this model, the density of the disk is assumed to have a power-law index of $p=-1.5$ or -2, as found in other low-mass envelopes. The envelope seems dynamically infalling toward the source with slow rotation because the kinematics is found to be roughly consistent with a free fall toward the source plus a rotation of a constant specific angular momentum. A 12CO outflow is seen surrounding the H2 jet, with a narrow waist around the source. Jetlike structures are also seen in 12CO near the source aligned with the H2 jet at high velocities. The morphological relationship between the H2 jet and the 12CO outflow, and the kinematics of the 12CO outflow along the jet axis are both consistent with those seen in a jet-driven bow shock model. SO emission is seen around the source and the H2 knotty shocks in the south, tracing shocked emission around them.