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Found 26 entries in the Bibliography.
Showing entries from 1 through 26
| 2023 |
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Magnetic Reconnection as the Driver of the Solar Wind We present EUV solar observations showing evidence for omnipresent jetting activity driven by small-scale magnetic reconnection at the base of the solar corona. We argue that the physical mechanism that heats and drives the solar wind at its source is ubiquitous magnetic reconnection in the form of small-scale jetting activity (a.k.a. jetlets). This jetting activity, like the solar wind and the heating of the coronal plasma, is ubiquitous regardless of the solar cycle phase. Each event arises from small-scale reconnection of ... Raouafi, Nour; Stenborg, G.; Seaton, D.~B.; Wang, H.; Wang, J.; DeForest, C.~E.; Bale, S.~D.; Drake, J.~F.; Uritsky, V.~M.; Karpen, J.~T.; DeVore, C.~R.; Sterling, A.~C.; Horbury, T.~S.; Harra, L.~K.; Bourouaine, S.; Kasper, J.~C.; Kumar, P.; Phan, T.~D.; Velli, M.; Published by: \apj Published on: mar YEAR: 2023 DOI: 10.3847/1538-4357/acaf6c Parker Data Used; Solar corona; Solar wind; magnetic fields; Solar magnetic reconnection; 1483; 1534; 994; 1504; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
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Parker Solar Probe: Four Years of Discoveries at Solar Cycle Minimum Launched on 12 Aug. 2018, NASA s Parker Solar Probe had completed 13 of its scheduled 24 orbits around the Sun by Nov. 2022. The mission s primary science goal is to determine the structure and dynamics of the Sun s coronal magnetic field, understand how the solar corona and wind are heated and accelerated, and determine what processes accelerate energetic particles. Parker Solar Probe returned a treasure trove of science data that far exceeded quality, significance, and quantity expectations, leading to a significant number ... Raouafi, N.~E.; Matteini, L.; Squire, J.; Badman, S.~T.; Velli, M.; Klein, K.~G.; Chen, C.~H.~K.; Matthaeus, W.~H.; Szabo, A.; Linton, M.; Allen, R.~C.; Szalay, J.~R.; Bruno, R.; Decker, R.~B.; Akhavan-Tafti, M.; Agapitov, O.~V.; Bale, S.~D.; Bandyopadhyay, R.; Battams, K.; Ber\vci\vc, L.; Bourouaine, S.; Bowen, T.~A.; Cattell, C.; Chandran, B.~D.~G.; Chhiber, R.; Cohen, C.~M.~S.; Amicis, R.; Giacalone, J.; Hess, P.; Howard, R.~A.; Horbury, T.~S.; Jagarlamudi, V.~K.; Joyce, C.~J.; Kasper, J.~C.; Kinnison, J.; Laker, R.; Liewer, P.; Malaspina, D.~M.; Mann, I.; McComas, D.~J.; Niembro-Hernandez, T.; Nieves-Chinchilla, T.; Panasenco, O.; y, Pokorn\; Pusack, A.; Pulupa, M.; Perez, J.~C.; Riley, P.; Rouillard, A.~P.; Shi, C.; Stenborg, G.; Tenerani, A.; Verniero, J.~L.; Viall, N.; Vourlidas, A.; Wood, B.~E.; Woodham, L.~D.; Woolley, T.; Published by: ßr Published on: feb YEAR: 2023 DOI: 10.1007/s11214-023-00952-4 Parker Data Used; Sun; Corona; Solar wind; plasma; magnetic fields; coronal mass ejections; parker solar probe; Astrophysics - Solar and Stellar Astrophysics; Physics - Plasma Physics; Physics - Space Physics |
| 2022 |
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Extracting the Heliographic Coordinates of Coronal Rays Using Images from WISPR/Parker Solar Probe The Wide-field Imager for Solar Probe (WISPR) onboard Parker Solar Probe (PSP), observing in white light, has a fixed angular field of view, extending from 13.5$^\ensuremath\circ$ to 108$^\ensuremath\circ$ from the Sun and approximately 50$^\ensuremath\circ$ in the transverse direction. In January 2021, on its seventh orbit, PSP crossed the heliospheric current sheet (HCS) near perihelion at a distance of 20 solar radii. At this time, WISPR observed a broad band of highly variable solar wind and multiple coronal rays. For si ... Liewer, P.~C.; Qiu, J.; Ark, F.; Penteado, P.; Stenborg, G.; Vourlidas, A.; Hall, J.~R.; Riley, P.; Published by: \solphys Published on: sep YEAR: 2022 DOI: 10.1007/s11207-022-02058-6 Parker Data Used; Corona; Coronal streamers; Coronal rays; Astrophysics - Solar and Stellar Astrophysics |
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Continued PSP/WISPR Observations of a Phaethon-related Dust Trail We present an update to the first white-light detections of a dust trail observed closely following the orbit of asteroid (3200) Phaethon, as seen by the Wide-field Imager for the Parker Solar Probe instrument on the NASA Parker Solar Probe mission. Here, we provide a summary and analysis of observations of the dust trail over nine separate mission encounters between 2018 October and 2021 August that saw the spacecraft approach to within 0.0277 au of the orbit of Phaethon. We find the photometric and estimated dust mass prop ... Battams, Karl; Gutarra-Leon, Angel; Gallagher, Brendan; Knight, Matthew; Stenborg, Guillermo; Tanner, Sarah; Linton, Mark; Szalay, Jamey; Kelley, Michael; Howard, Russell; Published by: \apj Published on: sep YEAR: 2022 DOI: 10.3847/1538-4357/ac83b5 Parker Data Used; Asteroids; Meteoroid dust clouds; Near-Earth objects; Small Solar System bodies; 72; 1039; 1092; 1469; Astrophysics - Earth and Planetary Astrophysics |
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The closest perihelion pass of Parker Solar Probe (PSP), so far, occurred between 2021 November 16 and 26 and reached \raisebox-0.5ex\textasciitilde13.29 R $_☉$ from Sun center. This pass resulted in very unique observations of the solar corona by the Wide-field Instrument for Solar PRobe (WISPR). WISPR observed at least 10 coronal mass ejections (CMEs), some of which were so close that the structures appear distorted. All of the CMEs appeared to have a magnetic flux rope (MFR) structure, and most were oriented such that t ... Howard, Russell; Stenborg, Guillermo; Vourlidas, Angelos; Gallagher, Brendan; Linton, Mark; Hess, Phillip; Rich, Nathan; Liewer, Paulett; Published by: \apj Published on: sep YEAR: 2022 DOI: 10.3847/1538-4357/ac7ff5 Parker Data Used; Solar coronal mass ejections; Solar wind; Solar K corona; Solar coronal streamers; 310; 1534; 2042; 1486; Astrophysics - Solar and Stellar Astrophysics; Astrophysics - Earth and Planetary Astrophysics |
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Coronal Mass Ejection Deformation at 0.1 au Observed by WISPR Although coronal mass ejections (CMEs) resembling flux ropes generally expand self-similarly, deformations along their fronts have been reported in observations and simulations. We present evidence of one CME becoming deformed after a period of self-similar expansion in the corona. The event was observed by multiple white-light imagers on 2021 January 20-22. The change in shape is evident in observations from the heliospheric imagers from the Wide-Field Imager for Solar Probe Plus (WISPR), which observed this CME for \raiseb ... Braga, Carlos; Vourlidas, Angelos; Liewer, Paulett; Hess, Phillip; Stenborg, Guillermo; Riley, Pete; Published by: \apj Published on: oct YEAR: 2022 DOI: 10.3847/1538-4357/ac90bf Parker Data Used; Solar coronal mass ejections; 310; Astrophysics - Solar and Stellar Astrophysics; Physics - Space Physics |
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Visible light observations from the Wide-field Imager for Solar PRobe (WISPR) aboard the Parker Solar Probe (PSP) mission offer a unique opportunity to study the dust environment near the Sun. The existence of a dust-free zone (DFZ) around stars was postulated almost a century ago. Despite numerous attempts to detect it from as close as 0.3 au, observational evidence of a circumsolar DFZ has remained elusive. Analysis of WISPR images obtained from heliocentric distances between 13.3-53.7 R $_\ensuremath\odot$ over multiple P ... Stenborg, Guillermo; Howard, Russell; Vourlidas, Angelos; Gallagher, Brendan; Published by: \apj Published on: jun YEAR: 2022 DOI: 10.3847/1538-4357/ac6b36 Parker Data Used; Circumstellar dust; Solar F corona; 236; 1991 |
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Clouds of Spacecraft Debris Liberated by Hypervelocity Dust Impacts on Parker Solar Probe Hypervelocity impacts on spacecraft surfaces produce a wide range of effects including transient plasma clouds, surface material ablation, and for some impacts, the liberation of spacecraft material as debris clouds. This study examines debris-producing impacts on the Parker Solar Probe spacecraft as it traverses the densest part of the zodiacal cloud: the inner heliosphere. Hypervelocity impacts by interplanetary dust grains on the spacecraft that produce debris clouds are identified and examined. Impact-generated plasma an ... Malaspina, David; Stenborg, Guillermo; Mehoke, Doug; Al-Ghazwi, Adel; Shen, Mitchell; Hsu, Hsiang-Wen; Iyer, Kaushik; Bale, Stuart; de Wit, Thierry; Published by: \apj Published on: jan YEAR: 2022 DOI: 10.3847/1538-4357/ac3bbb |
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Parker Solar Probe Imaging of the Night Side of Venus We present images of Venus from the Wide-Field Imager for Parker Solar Probe (WISPR) telescope on board the Parker Solar Probe (PSP) spacecraft, obtained during PSP s third and fourth flybys of Venus on 2020 July 11 and 2021 February 20, respectively. Thermal emission from the surface is observed on the night side, representing the shortest wavelength observations of this emission ever, the first detection of the Venusian surface by an optical telescope observing below 0.8 \ensuremath\mum. Consistent with previous observatio ... Wood, Brian; Hess, Phillip; Lustig-Yaeger, Jacob; Gallagher, Brendan; Korwan, Daniel; Rich, Nathan; Stenborg, Guillermo; Thernisien, Arnaud; Qadri, Syed; Santiago, Freddie; Peralta, Javier; Arney, Giada; Izenberg, Noam; Vourlidas, Angelos; Linton, Mark; Howard, Russell; Raouafi, Nour; Published by: \grl Published on: feb YEAR: 2022 DOI: 10.1029/2021GL096302 |
| 2021 |
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In-flight Calibration and Data Reduction for the WISPR Instrument On Board the PSP Mission We present the calibration status and data reduction methodology for the Wide Field Imager for Solar Probe (WISPR) on board the Parker Solar Probe (PSP) mission. In particular, we describe the process for converting a raw image, measured in digital numbers (DN), to a calibrated image, measured in mean solar brightness (MSB). We also discuss details of the on board image processing including bias removal, the linearity of the electronics, pointing, geometric distortion, and photometric calibration using stellar measurements, ... Hess, Phillip; Howard, Russell; Stenborg, Guillermo; Linton, Mark; Vourlidas, Angelos; Thernisien, Arnaud; Colaninno, Robin; Rich, Nathan; Wang, Dennis; Battams, Karl; Kuroda, Natsuha; Published by: Solar Physics Published on: 06/2021 YEAR: 2021 DOI: 10.1007/s11207-021-01847-9 |
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Pristine PSP/WISPR Observations of the Circumsolar Dust Ring near Venus s Orbit The Parker Solar Probe mission (PSP) has completed seven orbits around the Sun. The Wide-field Imager for Solar Probe (WISPR) on PSP consists of two visible light heliospheric imagers, which together image the interplanetary medium between 13°5 and 108° elongation. The PSP/WISPR nominal science observing window occurs during the solar encounters, which take place when the spacecraft (S/C) is within 0.25 au from the Sun. During Orbit 3, an extended science campaign took place while PSP transited between 0.5 and 0.25 au (dur ... Stenborg, Guillermo; Gallagher, Brendan; Howard, Russell; Hess, Phillip; Raouafi, Nour; Published by: The Astrophysical Journal Published on: 04/2021 YEAR: 2021 DOI: 10.3847/1538-4357/abe623 Parker Data Used; Solar F corona; Interplanetary dust; Circumstellar dust; 1991; 821; 236 |
| 2020 |
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Context. In 1929, Russell predicted that dust particles cannot survive in a region close to any star, hence giving justification for a dust free zone to exist inside a certain distance from the star. This theoretical prediction has not been confirmed, even with our Sun. \ Aims: We use the unique vantage points and new perspectives of the Parker Solar Probe (PSP) mission to study the dust environment close to the Sun with imaging observations from the Wide Field Imager for Solar Probe (WISPR) as PSP orbits, progressively clos ... Stenborg, G.; Howard, R.; Hess, P.; Gallagher, B.; Published by: Astronomy and Astrophysics Published on: jun YEAR: 2020 DOI: "10.1051/0004-6361/202039284" |
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The Wide-field Imager for Parker Solar Probe (WISPR) captures unprecedented white-light images of the solar corona and inner heliosphere. Thanks to the uniqueness of the Parker Solar Probe\textquoterights (PSP) orbit, WISPR is able to image "locally" coronal structures at high spatial and time resolutions. The observed plane of sky, however, rapidly changes because of the PSP\textquoterights high orbital speed. Therefore, the interpretation of the dynamics of the coronal structures recorded by WISPR is not straightforward ... Nisticò, Giuseppe; Bothmer, Volker; Vourlidas, Angelos; Liewer, Paulett; Thernisien, Arnaud; Stenborg, Guillermo; Howard, Russell; Published by: Solar Physics Published on: 04/2020 YEAR: 2020 DOI: 10.1007/s11207-020-01626-y Astrophysics - Solar and Stellar Astrophysics; Corona; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Detailed Imaging of Coronal Rays with the Parker Solar Probe The Wide-field Imager for Solar PRobe (WISPR) obtained the first high-resolution images of coronal rays at heights below 15 R☉ when the Parker Solar Probe (PSP) was located inside 0.25 au during the first encounter. We exploit these remarkable images to reveal the structure of coronal rays at scales that are not easily discernible in images taken from near 1 au. To analyze and interpret WISPR observations, which evolve rapidly both radially and longitudinally, we construct a latitude versus time map using the ... Poirier, Nicolas; Kouloumvakos, Athanasios; Rouillard, Alexis; Pinto, Rui; Vourlidas, Angelos; Stenborg, Guillermo; Valette, Emeline; Howard, Russell; Hess, Phillip; Thernisien, Arnaud; Rich, Nathan; Griton, Lea; Indurain, Mikel; Raouafi, Nour-Edine; Lavarra, Michael; Réville, Victor; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab6324 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Parker Solar Probe Observations of a Dust Trail in the Orbit of (3200) Phaethon We present the identification and preliminary analysis of a dust trail following the orbit of (3200) Phaethon as seen in white-light images recorded by the Wide-field Imager for Parker Solar Probe (WISPR) instrument on the NASA Parker Solar Probe (PSP) mission. During PSP\textquoterights first solar encounter in 2018 November, a dust trail following Phaethon\textquoterights orbit was visible for several days and crossing two fields of view. Preliminary analyses indicate this trail to have a visual magnitude of 15.8 \textp ... Battams, Karl; Knight, Matthew; Kelley, Michael; Gallagher, Brendan; Howard, Russell; Stenborg, Guillermo; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab6c68 Astrophysics - Earth and Planetary Astrophysics; Parker Data Used; parker solar probe; Solar Probe Plus |
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Morphological Reconstruction of a Small Transient Observed by Parker Solar Probe on 2018 November 5 On 2018 November 5, about 24 hr before the first close perihelion passage of Parker Solar Probe (PSP), a coronal mass ejection (CME) entered the field of view of the inner detector of the Wide-field Imager for Solar PRobe (WISPR) instrument on board PSP, with the northward component of its trajectory carrying the leading edge of the CME off the top edge of the detector about four hours after its first appearance. We connect this event to a very small jetlike transient observed from 1 au by coronagraphs on both the SOlar a ... Wood, Brian; Hess, Phillip; Howard, Russell; Stenborg, Guillermo; Wang, Yi-Ming; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab5219 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Relating Streamer Flows to Density and Magnetic Structures at the Parker Solar Probe The physical mechanisms that produce the slow solar wind are still highly debated. Parker Solar Probe\textquoterights (PSP\textquoterights) second solar encounter provided a new opportunity to relate in situ measurements of the nascent slow solar wind with white-light images of streamer flows. We exploit data taken by the Solar and Heliospheric Observatory, the Solar TErrestrial RElations Observatory (STEREO), and the Wide Imager on Solar Probe to reveal for the first time a close link between imaged streamer flows and th ... Rouillard, Alexis; Kouloumvakos, Athanasios; Vourlidas, Angelos; Kasper, Justin; Bale, Stuart; Raouafi, Nour-Edine; Lavraud, Benoit; Howard, Russell; Stenborg, Guillermo; Stevens, Michael; Poirier, Nicolas; Davies, Jackie; Hess, Phillip; Higginson, Aleida; Lavarra, Michael; Viall, Nicholeen; Korreck, Kelly; Pinto, Rui; Griton, Lea; eville, Victor; Louarn, Philippe; Wu, Yihong; Dalmasse, K\; enot, Vincent; Case, Anthony; Whittlesey, Phyllis; Larson, Davin; Halekas, Jasper; Livi, Roberto; Goetz, Keith; Harvey, Peter; MacDowall, Robert; Malaspina, D.; Pulupa, M.; Bonnell, J.; de Witt, Dudok; Penou, Emmanuel; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab579a Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Solar Probe Plus |
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WISPR Imaging of a Pristine CME The Wide-field Imager for Solar Probe (WISPR) on board the Parker Solar Probe (PSP) observed a coronal mass ejection (CME) on 2018 November 1, the first day of the initial PSP encounter. The speed of the CME, approximately 200-300 km s-1 in the WISPR field of view, is typical of slow, streamer blowout CMEs. This event was also observed by the Large Angle and Spectrometric Coronagraph Experiment (LASCO) coronagraphs. WISPR and LASCO view remarkably similar structures that enable useful cross-comparison between t ... Hess, Phillip; Rouillard, Alexis; Kouloumvakos, Athanasios; Liewer, Paulett; Zhang, Jie; Dhakal, Suman; Stenborg, Guillermo; Colaninno, Robin; Howard, Russell; Published by: The Astrophysical Journal Supplement Series Published on: 02/2020 YEAR: 2020 DOI: 10.3847/1538-4365/ab4ff0 Astrophysics - Solar and Stellar Astrophysics; Parker Data Used; parker solar probe; Physics - Space Physics; Solar Probe Plus |
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Modeling the Early Evolution of a Slow Coronal Mass Ejection Imaged by the Parker Solar Probe During its first solar encounter, the Parker Solar Probe (PSP) acquired unprecedented up-close imaging of a small coronal mass ejection (CME) propagating in the forming slow solar wind. The CME originated as a cavity imaged in extreme ultraviolet that moved very slowly (<50 km s(-1)) to 3-5 solar radii (R), where it then accelerated to supersonic speeds. We present a new model of an erupting flux rope (FR) that computes the forces acting on its expansion with a computation of its internal magnetic field in three dimensions. ... Rouillard, Alexis; Poirier, Nicolas; Lavarra, Michael; Bourdelle, Anthony; Dalmasse, Kevin; Kouloumvakos, Athanasios; Vourlidas, Angelos; Kunkel, Valbona; Hess, Phillip; Howard, Russ; Stenborg, Guillermo; Raouafi, Nour; Published by: ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES Published on: 02/2019 YEAR: 2020 DOI: 10.3847/1538-4365/ab6610 |
| 2019 |
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Near-Sun observations of an F-corona decrease and K-corona fine structure Remote observations of the solar photospheric light scattered by electrons (the K-corona) and dust (the F-corona or zodiacal light) have been made from the ground during eclipses and from space at distances as small as 0.3 astronomical units to the Sun. Previous observations of dust scattering have not confirmed the existence of the theoretically predicted dust-free zone near the Sun. The transient nature of the corona has been well characterized for large events, but questions still remain (for example, about the initiat ... Howard, R.; Vourlidas, A.; Bothmer, V.; Colaninno, R.; Deforest, C.; Gallagher, B.; Hall, J.; Hess, P.; Higginson, A.; Korendyke, C.; Kouloumvakos, A.; Lamy, P.; Liewer, P.; Linker, J.; Linton, M.; Penteado, P.; Plunkett, S.; Poirier, N.; Raouafi, N.; Rich, N.; Rochus, P.; Rouillard, A.; Socker, D.; Stenborg, G.; Thernisien, A.; Viall, N.; Published by: Nature Published on: 12/2019 YEAR: 2019 DOI: 10.1038/s41586-019-1807-x |
| 2018 |
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Evidence for a Circumsolar Dust Ring Near Mercury\textquoterights Orbit To test a technique to be used on the white-light imager onboard the recently launched Parker Solar Probe mission, we performed a numerical differentiation of the brightness profiles along the photometric axis of the F-corona models that are derived from STEREO Ahead Sun Earth Connection Heliospheric Investigation observations recorded with the HI-1 instrument between 2007 December and 2014 March. We found a consistent pattern in the derivatives that can be observed from any S/C longitude between about 18\textdegree and 2 ... Stenborg, Guillermo; Stauffer, Johnathan; Howard, Russell; Published by: The Astrophysical Journal Published on: 11/2018 YEAR: 2018 DOI: 10.3847/1538-4357/aae6cb 169P\&NEAT; 73P\&Schwassmann-Wachmann 3; comets: individual: 2P\&Encke; methods: data analysis; Parker Data Used; parker solar probe; Solar Probe Plus; techniques: image processing; zodiacal dust |
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Stenborg, Guillermo; Howard, Russell; Stauffer, Johnathan; Published by: \apj Published on: 08/2018 YEAR: 2018 DOI: 10.3847/1538-4357/aacea3 Parker Data Used; methods: data analysis; scattering; Sun: corona; techniques: image processing; zodiacal dust |
| 2017 |
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Stenborg, Guillermo; Howard, Russell; Published by: \apj Published on: 10/2017 YEAR: 2017 DOI: 10.3847/1538-4357/aa8ef0 Parker Data Used; methods: data analysis; Sun: corona; techniques: image processing |
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White-light coronal and heliospheric imagers observe scattering of photospheric light from both dust particles (the F-Corona) and free electrons in the corona (the K-corona). The separation of the two coronae is thus vitally important to reveal the faint K-coronal structures (e.g., streamers, co-rotating interaction regions, coronal mass ejections, etc.). However, the separation of the two coronae is very difficult, so we are content in defining a background corona that contains the F- and as little K- as possible. For bo ... Stenborg, Guillermo; Howard, Russell; Published by: The Astrophysical Journal Published on: 04/2017 YEAR: 2017 DOI: 10.3847/1538-4357/aa6a12 methods: data analysis; parker solar probe; Solar Probe Plus; Sun: corona; Sun: coronal mass ejections: CMEs; techniques: image processing |
| 2015 |
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Dynamics of HVECs emitted from comet C/2011 L4 as observed by STEREO Raouafi, N.; Lisse, C.~M.; Stenborg, G.; Jones, G.~H.; Schmidt, C.~A.; Published by: Journal of Geophysical Research (Space Physics) Published on: 07/2015 YEAR: 2015 DOI: 10.1002/2014JA020926 Parker Data Used; comets: general; comets: individual (C/2011 L4); Sun: magnetic fields; Sun: solar wind; Astrophysics - Earth and Planetary Astrophysics |
| 2014 |
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Role of Transients in the Sustainability of Solar Coronal Plumes Published by: \apj Published on: 06/2014 YEAR: 2014 DOI: 10.1088/0004-637X/787/2/118 Parker Data Used; plasmas; Sun: activity; Sun: corona; Sun: magnetic fields; Sun: UV radiation |
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