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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 271 records · Page 15
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DOE OSTI2011

STARSPOTS DUE TO LARGE-SCALE VORTICES IN ROTATING TURBULENT CONVECTION

We study the generation of large-scale vortices in rotating turbulent convection by means of Cartesian direct numerical simulations. We find that for sufficiently rapid rotation, cyclonic structures on a scale large in comparison to that of the convective eddies emerge, provided that the fluid Reynolds number exceeds a critical value. For slower rotation, cool cyclonic vortices are preferred, whereas for rapid rotation, warm anti-cyclonic vortices are favored. In some runs in the intermediate regime both types of cyclones coexist for thousands of convective turnover times. The temperature contrast between the vortices and the surrounding atmosphere is of the order of 5%. We relate the simulation results to observations of rapidly rotating late-type stars that are known to exhibit large high-latitude spots from Doppler imaging. In many cases, cool spots are accompanied with spotted regions with temperatures higher than the average. In this paper, we investigate a scenario according to which of the spots observed in the temperature maps could have a non-magnetic origin due to large-scale vortices in the convection zones of the stars.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2012

THE ROLE OF GALAXY INTERACTION IN ENVIRONMENTAL DEPENDENCE OF THE STAR FORMATION ACTIVITY AT z {approx_equal} 1.2

In order to understand environmental effects on star formation in high-redshift galaxies, we investigate the physical relationships between the star formation activity, stellar mass, and environment for z {approx_equal} 1.2 galaxies in the 2 deg{sup 2} COSMOS field. We estimate star formation using the [O II]{lambda}3727 emission line and environment from the local galaxy density. Our analysis shows that for massive galaxies (M{sub *} {approx}> 10{sup 10} M{sub Sun }), the fraction of [O II] emitters in high-density environments ({Sigma}{sub 10th} {approx}> 3.9 Mpc{sup -2}) is 1.7 {+-} 0.4 times higher than in low-density environments ({Sigma}{sub 10th} {approx}< 1.5 Mpc{sup -2}), while the [O II] emitter fraction does not depend on environment for low-mass M{sub *} {approx}< 10{sup 10} M{sub Sun} galaxies. In order to understand what drives these trends, we investigate the role of companion galaxies in our sample. We find that the fraction of [O II] emitters in galaxies with companions is 2.4 {+-} 0.5 times as high as that in galaxies without companions at M{sub *} {approx}> 10{sup 10} M{sub Sun }. In addition, massive galaxies are more likely to have companions in high-density environments. However, although the number of star-forming galaxies increases for massive galaxies with close companions and in dense environments, the average star formation rate of star-forming galaxies at a given mass is independent of environment and the presence/absence of a close companion. These results suggest that interactions and/or mergers in a high-density environment could induce star formation in massive galaxies at z {approx} 1.2, increasing the fraction of star-forming galaxies with M{sub *} {approx}> 10{sup 10} M{sub Sun }.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2013

KEPLER-63b: A GIANT PLANET IN A POLAR ORBIT AROUND A YOUNG SUN-LIKE STAR

We present the discovery and characterization of a giant planet orbiting the young Sun-like star Kepler-63 (KOI-63, m{sub Kp} = 11.6, T{sub eff} = 5576 K, M{sub *} = 0.98 M{sub ☉}). The planet transits every 9.43 days, with apparent depth variations and brightening anomalies caused by large starspots. The planet's radius is 6.1 ± 0.2 R{sub ⊕}, based on the transit light curve and the estimated stellar parameters. The planet's mass could not be measured with the existing radial-velocity data, due to the high level of stellar activity, but if we assume a circular orbit, then we can place a rough upper bound of 120 M{sub ⊕} (3σ). The host star has a high obliquity (ψ = 104°), based on the Rossiter-McLaughlin effect and an analysis of starspot-crossing events. This result is valuable because almost all previous obliquity measurements are for stars with more massive planets and shorter-period orbits. In addition, the polar orbit of the planet combined with an analysis of spot-crossing events reveals a large and persistent polar starspot. Such spots have previously been inferred using Doppler tomography, and predicted in simulations of magnetic activity of young Sun-like stars.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2015

Detecting the companions and ellipsoidal variations of RS CVN primaries. II. o Draconis, A candidate for recent low-mass companion ingestion

To measure the stellar and orbital properties of the metal-poor RS CVn binary o Draconis (o Dra), we directly detect the companion using interferometric observations obtained with the Michigan InfraRed Combiner at Georgia State University's Center for High Angular Resolution Astronomy (CHARA) Array. The H-band flux ratio between the primary and secondary stars is the highest confirmed flux ratio (370 ± 40) observed with long-baseline optical interferometry. These detections are combined with radial velocity data of both the primary and secondary stars, including new data obtained with the Tillinghast Reflector Echelle Spectrograph on the Tillinghast Reflector at the Fred Lawrence Whipple Observatory and the 2 m Tennessee State University Automated Spectroscopic Telescope at Fairborn Observatory. We determine an orbit from which we find model-independent masses and ages of the components (M{sub A}=1.35±0.05 M{sub ⊙}, M{sub B}=0.99±0.02 M{sub ⊙}, system age = 3.0∓0.5 Gyr). An average of a 23-year light curve of o Dra from the Tennessee State University Automated Photometric Telescope folded over the orbital period newly reveals eclipses and the quasi-sinusoidal signature of ellipsoidal variations. The modeled light curve for our system's stellar and orbital parameters confirm these ellipsoidal variations due to the primary star partially filling its Roche lobe potential, suggesting most of the photometric variations are not due to stellar activity (starspots). Measuring gravity darkening from the average light curve gives a best-fit of β=0.07±0.03, a value consistent with conventional theory for convective envelope stars. The primary star also exhibits an anomalously short rotation period, which, when taken with other system parameters, suggests the star likely engulfed a low-mass companion that had recently spun-up the star.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2010

STRUCTURE AND FEEDBACK IN 30 DORADUS. I. OBSERVATIONS

We have completed a new optical imaging and spectrophotometric survey of a 140 x 80 pc{sup 2} region of 30 Doradus centered on R136, covering key optical diagnostic emission lines including H{alpha}, H{beta}, H{gamma}, [O III] {lambda}{lambda}4363, 4959, 5007, [N II] {lambda}{lambda}6548, 6584, [S II] {lambda}{lambda}6717, 6731 [S III] {lambda}6312, and in some locations [S III] {lambda}9069. We present maps of fluxes and intensity ratios for these lines, and catalogs of isolated ionizing stars, elephant-trunk pillars, and edge-on ionization fronts. The final science-quality spectroscopic data products are available to the public. Our analysis of the new data finds that, while stellar winds and supernovae undoubtedly produce shocks and are responsible for shaping the nebula, there are no global spectral signatures to indicate that shocks are currently an important source of ionization. We conclude that the considerable region covered by our survey is well described by photoionization from the central cluster where the ionizing continuum is dominated by the most massive O stars. We show that if 30 Dor were viewed at a cosmological distance, its integrated light would be dominated by its extensive regions of lower surface brightness rather than by the bright, eye-catching arcs.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2010

THE IMPACT OF HOT JUPITERS ON THE SPIN-DOWN OF THEIR HOST STARS

We present a numerical magnetohydrodynamic study of the dependence of stellar mass and angular momentum loss rates on the orbital distance to close-in giant planets. We find that the mass loss rate drops by a factor of {approx}1.5-2, while the angular momentum loss rate drops by a factor of {approx}4 as the distance decreases past the Alfven surface. This reduction in angular momentum loss is due to the interaction between the stellar and planetary Alfven surfaces, which modifies the global structure of the stellar corona and stellar wind on the hemisphere facing the planet, as well as on the opposite hemisphere. The simulation also shows that the magnitude of change in angular momentum loss rate depends mostly on the strength of the planetary magnetic field and not on its polarity. The interaction, however, begins at greater separation if the overall field topology of the star and the planet are anti-aligned. Our results are consistent with evidence for excess angular momentum in stars harboring close-in giant planets and show that the reduction in wind-driven angular momentum loss can compete with, and perhaps dominate, spin-up due to tidal interaction.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2010

TYPE IIP SUPERNOVA 2009kf: EXPLOSION DRIVEN BY BLACK HOLE ACCRETION?

The unusually bright type IIP supernova (SN) 2009kf is studied employing hydrodynamic modeling. We derived optimal values of the ejecta mass of 28.1 M{sub sun}, explosion energy of 2.2 x 10{sup 52} erg, and presupernova radius of 2 x 10{sup 3} R{sub sun} assuming that {sup 56}Ni mass is equal to the upper limit of 0.4 M{sub sun}. We analyzed effects of the uncertainties in the extinction and {sup 56}Ni mass and concluded that both the ejecta mass and explosion energy cannot be significantly reduced compared with the optimal values. The huge explosion energy of SN 2009kf indicates that the explosion is caused by the same mechanism which operates in energetic SNe Ibc (hypernovae), i.e., via a rapid disk accretion onto black hole. The ejecta mass combined with the black hole mass and the mass lost by stellar wind yields the progenitor mass of about 36 M{sub sun}. We propose a scenario in which massive binary evolution might result in the SN 2009kf event.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2010

DISCOVERY OF TWIN WOLF-RAYET STARS POWERING DOUBLE RING NEBULAE

We have spectroscopically discovered a pair of twin, nitrogen-type, hydrogen-rich, Wolf-Rayet stars (WN8-9h) that are both surrounded by circular, mid-infrared-bright nebulae detected with the Spitzer Space Telescope and MIPS instrument. The emission is probably dominated by a thermal continuum from cool dust, but also may contain contributions from atomic line emission. There is no counterpart at shorter Spitzer/IRAC wavelengths, indicating a lack of emission from warm dust. The two nebulae are probably wind-swept stellar ejecta released by the central stars during a prior evolutionary phase. The nebulae partially overlap on the sky and we speculate on the possibility that they are in the early stage of a collision. Two other evolved massive stars have also been identified within the area subtended by the nebulae, including a carbon-type Wolf-Rayet star (WC8) and an O7-8 III-I star, the latter of which appears to be embedded in one of the larger WN8-9h nebulae. The derived distances to these stars imply that they are coeval members of an association lying 4.9 {+-} 1.2 kpc from Earth, near the intersection of the Galaxy's Long Bar and the Scutum-Centaurus spiral arm. This new association represents an unprecedented display of complex interactions between multiple stellar winds, outflows, and the radiation fields of evolved massive stars.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2011

XMM-NEWTON OBSERVATIONS REVEAL VERY HIGH X-RAY LUMINOSITY FROM THE CARBON-RICH WOLF-RAYET STAR WR 48a

We present XMM-Newton observations of the dusty Wolf-Rayet (W-R) star WR 48a. This is the first detection of this object in X-rays. The XMM-Newton EPIC spectra are heavily absorbed and the presence of numerous strong emission lines indicates a thermal origin of the WR 48a X-ray emission, with dominant temperature components at kT{sub cool} {approx} 1 keV and kT{sub hot} {approx} 3 keV, the hotter component dominating the observed flux. No significant X-ray variability was detected on timescales {<=}1 day. Although the distance to WR 48a is uncertain, if it is physically associated with Open clusters Danks 1 and 2 at d {approx}4 kpc, then the resultant X-ray luminosity L{sub X}{approx} 10{sup 35} erg s{sup -1} makes it the most X-ray luminous W-R star in the Galaxy detected so far, after the black hole candidate Cyg X-3. We assume the following scenarios as the most likely explanation for the X-ray properties of WR 48a: (1) colliding stellar winds in a wide WR+O binary system, or in a hierarchical triple system with non-degenerate stellar components and (2) accretion shocks from the WR 48a wind onto a close companion (possibly a neutron star). More specific information about WR 48a and its wind properties will be needed to distinguish between the above possibilities.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2011

DISCOVERY OF EXTENDED AND VARIABLE RADIO STRUCTURE FROM THE GAMMA-RAY BINARY SYSTEM PSR B1259-63/LS 2883

PSR B1259-63 is a 48 ms pulsar in a highly eccentric 3.4 year orbit around the young massive star LS 2883. During the periastron passage the system displays transient non-thermal unpulsed emission from radio to very high energy gamma rays. It is one of the three galactic binary systems clearly detected at TeV energies, together with LS 5039 and LS I +61 303. We observed PSR B1259-63 after the 2007 periastron passage with the Australian Long Baseline Array at 2.3 GHz to trace the milliarcsecond (mas) structure of the source at three different epochs. We have discovered extended and variable radio structure. The peak of the radio emission is detected outside the binary system near periastron, at projected distances of 10-20 mas (25-45 AU assuming a distance of 2.3 kpc). The total extent of the emission is {approx}50 mas ({approx}120 AU). This is the first observational evidence that non-accreting pulsars orbiting massive stars can produce variable extended radio emission at AU scales. Similar structures are also seen in LS 5039 and LS I +61 303, in which the nature of the compact object is unknown. The discovery presented here for the young non-accreting pulsar PSR B1259-63 reinforces the link with these two sources and supports the presence of pulsars in these systems as well. A simple kinematical model considering only a spherical stellar wind can approximately trace the extended structures if the binary system orbit has a longitude of the ascending node of {Omega} {approx} -40{sup 0} and a magnetization parameter of {sigma} {approx} 0.005.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2011

COMPUTING THE DUST DISTRIBUTION IN THE BOW SHOCK OF A FAST-MOVING, EVOLVED STAR

We study the hydrodynamical behavior occurring in the turbulent interaction zone of a fast-moving red supergiant star, where the circumstellar and interstellar material collide. In this wind-interstellar-medium collision, the familiar bow shock, contact discontinuity, and wind termination shock morphology form, with localized instability development. Our model includes a detailed treatment of dust grains in the stellar wind and takes into account the drag forces between dust and gas. The dust is treated as pressureless gas components binned per grain size, for which we use 10 representative grain size bins. Our simulations allow us to deduce how dust grains of varying sizes become distributed throughout the circumstellar medium. We show that smaller dust grains (radius <0.045 {mu}m) tend to be strongly bound to the gas and therefore follow the gas density distribution closely, with intricate fine structure due to essentially hydrodynamical instabilities at the wind-related contact discontinuity. Larger grains which are more resistant to drag forces are shown to have their own unique dust distribution, with progressive deviations from the gas morphology. Specifically, small dust grains stay entirely within the zone bound by shocked wind material. The large grains are capable of leaving the shocked wind layer and can penetrate into the shocked or even unshocked interstellar medium. Depending on how the number of dust grains varies with grain size, this should leave a clear imprint in infrared observations of bow shocks of red supergiants and other evolved stars.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2011

TIDALLY ENHANCED STELLAR WIND: A WAY TO MAKE THE SYMBIOTIC CHANNEL TO TYPE Ia SUPERNOVA VIABLE

In the symbiotic (or WD+RG) channel of the single-degenerate scenario for type Ia supernovae (SNe Ia), the explosions occur a relatively long time after star formation. The birthrate from this channel would be too low to account for all observed SNe Ia were it not for some mechanism to enhance the rate of accretion on to the white dwarf. A tidally enhanced stellar wind, of the type which has been postulated to explain many phenomena related to giant star evolution in binary systems, can do this. Compared to mass stripping, this model extends the space of SNe Ia progenitors to longer orbital periods and hence increases the birthrate to about 0.0069 yr{sup -1} for the symbiotic channel. Two symbiotic stars, T CrB and RS Oph, considered to be the most likely progenitors of SNe Ia through the symbiotic channel, are well inside the period-companion mass space predicted by our models.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2011

VISIBILITY STACKING IN THE QUEST FOR TYPE Ia SUPERNOVA RADIO EMISSION

We describe the process of stacking radio interferometry visibilities to form a deep composite image and its application to the observation of transient phenomena. We apply 'visibility stacking' to 46 archival Very Large Array observations of nearby type Ia supernovae (SNeIa). This new approach provides an upper limit on the SNIa ensemble peak radio luminosity of 1.2 x 10{sup 25} erg s{sup -1} Hz{sup -1} at 5 GHz, which is 5-10 times lower than previously measured. This luminosity implies an upper limit on the average companion stellar wind mass-loss rate of 1.3 x 10{sup -7} M{sub sun} yr{sup -1}. This mass-loss rate is consistent with the double degenerate scenario for SNeIa and rules out intermediate- and high-mass companions in the single degenerate scenario. In the era of time domain astronomy, techniques such as visibility stacking will be important in extracting the maximum amount of information from observations of populations of short-lived events.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2011

THE FORMATION OF FULLERENES: CLUES FROM NEW C{sub 60}, C{sub 70}, AND (POSSIBLE) PLANAR C{sub 24} DETECTIONS IN MAGELLANIC CLOUD PLANETARY NEBULAE

We present 10 new Spitzer detections of fullerenes in Magellanic Cloud Planetary Nebulae, including the first extragalactic detections of the C{sub 70} molecule. These new fullerene detections together with the most recent laboratory data permit us to report an accurate determination of the C{sub 60} and C{sub 70} abundances in space. Also, we report evidence for the possible detection of planar C{sub 24} in some of our fullerene sources, as indicated by the detection of very unusual emission features coincident with the strongest transitions of this molecule at {approx}6.6, 9.8, and 20 {mu}m. The infrared spectra display a complex mix of aliphatic and aromatic species such as hydrogenated amorphous carbon grains (HACs), polycyclic aromatic hydrocarbon clusters, fullerenes, and small dehydrogenated carbon clusters (possible planar C{sub 24}). The coexistence of such a variety of molecular species supports the idea that fullerenes are formed from the decomposition of HACs. We propose that fullerenes are formed from the destruction of HACs, possibly as a consequence of shocks driven by the fast stellar winds, which can sometimes be very strong in transition sources and young planetary nebulae (PNe). This is supported by the fact that many of our fullerene-detected PNe show altered [Ne III]/[Ne II] ratios suggestive of shocks as well as P-Cygni profiles in their UV lines indicative of recently enhanced mass loss.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2011

ON THE MASS-LOSS RATE OF MASSIVE STARS IN THE LOW-METALLICITY GALAXIES IC 1613, WLM, AND NGC 3109

We present a spectroscopic analysis of Very Large Telescope/X-Shooter observations of six O-type stars in the low-metallicity (Z {approx} 1/7 Z {sub sun}) galaxies IC 1613, WLM, and NGC 3109. The stellar and wind parameters of these sources allow us, for the first time, to probe the mass loss versus metallicity dependence of stellar winds at metallicities below that of the Small Magellanic Cloud (at Z {approx} 1/5 Z {sub sun}) by means of a modified wind momentum versus luminosity diagram. The wind strengths that we obtain for the objects in WLM and NGC 3109 are unexpectedly high and do not agree with theoretical predictions. The objects in IC 1613 tend toward a higher than expected mass-loss rate, but remain consistent with predictions within their error bars. We discuss potential systematic uncertainties in the mass-loss determinations to explain our results. However, if further scrutinization of these findings point towards an intrinsic cause for this unexpected sub-SMC mass-loss behavior, implications would include a higher than anticipated number of Wolf-Rayet stars and Ib/Ic supernovae in low-metallicity environments, but a reduced number of long-duration gamma-ray bursts produced through a single-star evolutionary channel.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2021

Scheduling strategies for the ESPRESSO follow-up of TESS targets

ABSTRACT Radial-velocity follow-up of stars harbouring transiting planets detected by TESS is expected to require very large amounts of expensive telescope time in the next few years. Therefore, scheduling strategies should be implemented to maximize the amount of information gathered about the target planetary systems. We consider myopic and non-myopic versions of a novel uniform-in-phase scheduler, as well as a random scheduler, and compare these scheduling strategies with respect to the bias, accuracy and precision achieved in recovering the mass and orbital parameters of transiting and non-transiting planets. This comparison is carried out based on realistic simulations of radial-velocity follow-up with ESPRESSO of a sample of 50 TESS target stars, with simulated planetary systems containing at least one transiting planet with a radius below 4R⊕. Radial-velocity data sets were generated under reasonable assumptions about their noise component, including that resulting from stellar activity, and analysed using a fully Bayesian methodology. We find the random scheduler leads to a more biased, less accurate, and less precise, estimation of the mass of the transiting exoplanets. No significant differences are found between the results of the myopic and non-myopic implementations of the uniform-in-phase scheduler. With only about 22 radial velocity measurements per data set, our novel uniform-in-phase scheduler enables an unbiased (at the level of 1 per cent) measurement of the masses of the transiting planets, while keeping the average relative accuracy and precision around 16 per cent and 23 per cent, respectively. The number of non-transiting planets detected is similar for all the scheduling strategies considered, as well as the bias, accuracy and precision with which their masses and orbital parameters are recovered.

Cabona, L.↗
DOE OSTI2024

Short-period post-common envelope binaries with Balmer emission from SDSS and LAMOST based on ZTF photometric data

ABSTRACT We present here 55 short-period post-common envelope binaries (PCEBs) containing a hot white dwarf (WD) and a low-mass main sequence (MS). Based on the photometric data from Zwicky Transient Facility survey data Release 19 (ZTF DR19), the light curves are analysed for about 200 WDMS binaries with emission line(s) identified from the Sloan Digital Sky Survey (SDSS) or the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) spectra, in which 55 WDMS binaries are found to exhibit variability in their luminosities with a short period and are thus short-period binaries (i.e. PCEBs). In addition, it is found that the orbital periods of these PCEBs locate in a range from 2.2643 to 81.1526 h. However, only six short-period PCEBs are newly discovered and the orbital periods of 19 PCEBs are improved in this work. Meanwhile, it is found that three objects are newly discovered eclipsing PCEBs, and a object (i.e. SDSS J1541) might be the short-period PCEB with a late M-type star or a brown dwarf companion based on the analysis of its spectral energy distribution. At last, the mechanism(s) being responsible for the emission features in the spectra of these PCEBs are discussed, the emission features arising in their optical spectra might be caused by the stellar activity or an irradiated component owing to a hot WD companion because most of them contain a WD with an effective temperature higher than $\sim$10 000 K.

Li, Lifang↗
DOE OSTI2023

Star-exoplanet interactions: A growing interdisciplinary field in heliophysics

Traditionally, heliophysics is characterized as the study of the near-Earth space environment, where plasmas and neutral gases originating from the Earth, the Sun, and other solar system bodies interact in ways that are detectable only through in-situ or close-range (usually within ~10 AU) remote sensing. As a result, heliophysics has data from the space environment around a handful of solar system objects, in particular the Sun and Earth. Comparatively, astrophysics has data from an extensive array of objects, but is more limited in temporal, spatial, and wavelength information from any individual object. Thus, our understanding of planetary space environments as a complex, multi-dimensional network of specific interacting systems may in the past have seemed to have little to do with the highly diverse space environments detected through astrophysical methods. Recent technological advances have begun to bridge this divide. Exoplanetary studies are opening up avenues to study planetary environments beyond our solar system, with missions like Kepler, TESS, and JWST, along with increasing capabilities of ground-based observations. At the same time, heliophysics studies are pushing beyond the boundaries of our heliosphere with Voyager, IBEX, and the future IMAP mission. The interdisciplinary field of star-exoplanet interactions is a critical, growing area of study that enriches heliophysics. A multidisciplinary approach to heliophysics enables us to better understand universal processes that operate in diverse environments, as well as the evolution of our solar system and extreme space weather. The expertise, data, theory, and modeling tools developed by heliophysicists are crucial in understanding the space environments of exoplanets, their host stars, and their potential habitability. The mutual benefit that heliophysics and exoplanetary studies offer each other depends on strong, continuing solar system-focused and Earth-focused heliophysics studies. The heliophysics discipline requires new targeted funding to support inter-divisional opportunities, including small multi-disciplinary research projects, large collaborative research teams, and observations targeting the heliophysics of planetary and exoplanet systems. Here we discuss areas of heliophysics-relevant exoplanetary research, observational opportunities and challenges, and ways to promote the inclusion of heliophysics within the wider exoplanetary community.

79 ASTRONOMY AND ASTROPHYSICS↗