Search Publications
Impact of space weather on climate and habitability of terrestrial-type exoplanets
Luhmann, J. G.; France, K.; Verkhoglyadova, O. P. +44 more
The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify t…
CME-CME Interactions as Sources of CME Geoeffectiveness: The Formation of the Complex Ejecta and Intense Geomagnetic Storm in 2017 Early September
Veronig, Astrid M.; Dumbović, Mateja; Temmer, Manuela +9 more
Coronal mass ejections (CMEs) are the primary sources of intense disturbances at Earth, where their geoeffectiveness is largely determined by their dynamic pressure and internal magnetic field, which can be significantly altered during interactions with other CMEs in interplanetary space. We analyze three successive CMEs that erupted from the Sun …
Meridional flow in the Sun’s convection zone is a single cell in each hemisphere
Gizon, Laurent; Cameron, Robert H.; Liang, Zhi-Chao +4 more
The Sun’s magnetic field is generated by subsurface motions of the convecting plasma. The latitude at which the magnetic field emerges through the solar surface (as sunspots) drifts toward the equator over the course of the 11-year solar cycle. We use helioseismology to infer the meridional flow (in the latitudinal and radial directions) over two …
Initiation and Early Kinematic Evolution of Solar Eruptions
Inhester, B.; Cheng, X.; Ding, M. D. +5 more
We investigate the initiation and early evolution of 12 solar eruptions, including six active-region hot channel and six quiescent filament eruptions, which were well observed by the Solar Dynamics Observatory, as well as by the Solar Terrestrial Relations Observatory for the latter. The sample includes one failed eruption and 11 coronal mass ejec…
Models and data analysis tools for the Solar Orbiter mission
Fedorov, A.; Budnik, E.; Williams, D. +102 more
Context. The Solar Orbiter spacecraft will be equipped with a wide range of remote-sensing (RS) and in situ (IS) instruments to record novel and unprecedented measurements of the solar atmosphere and the inner heliosphere. To take full advantage of these new datasets, tools and techniques must be developed to ease multi-instrument and multi-spacec…
Radial Evolution of Coronal Mass Ejections Between MESSENGER, Venus Express, STEREO, and L1: Catalog and Analysis
Lugaz, N.; Winslow, R. M.; Salman, T. M.
Our knowledge of the properties of coronal mass ejections (CMEs) in the inner heliosphere is constrained by the relative lack of plasma observations between the Sun and 1 AU. In this work, we present a comprehensive catalog of 47 CMEs measured in situ measurements by two or more radially aligned spacecraft (MESSENGER, Venus Express, STEREO, Wind/A…
Magnitude and direction of the local interstellar magnetic field inferred from Voyager 1 and 2 interstellar data and global heliospheric model
Izmodenov, Vladislav V.; Alexashov, Dmitry B.
In this Letter, we provide constraints on the direction and magnitude of the pristine (i.e., unperturbed by the interaction with the Sun) local interstellar magnetic field. The constraints are based on analysis of the interstellar magnetic field components at the heliopause measured by magnetometer instruments on board Voyager 1 and 2 spacecraft. …
Relating Streamer Flows to Density and Magnetic Structures at the Parker Solar Probe
Vourlidas, Angelos; Lavraud, Benoit; Poirier, Nicolas +34 more
The physical mechanisms that produce the slow solar wind are still highly debated. Parker Solar Probe's (PSP's) 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 TErrest…
Magnetic Reconnection during the Post-impulsive Phase of a Long-duration Solar Flare: Bidirectional Outflows as a Cause of Microwave and X-Ray Bursts
Reeves, Katharine K.; Chen, Bin; Yu, Sijie +5 more
Magnetic reconnection plays a crucial role in powering solar flares, production of energetic particles, and plasma heating. However, where the magnetic reconnections occur, how and where the released magnetic energy is transported, and how it is converted to other forms remain unclear. Here we report recurring bidirectional plasma outflows located…
Exploring Solar Wind Origins and Connecting Plasma Flows from the Parker Solar Probe to 1 au: Nonspherical Source Surface and Alfvénic Fluctuations
D'Amicis, Raffaella; Réville, Victor; Velli, Marco +18 more
The magnetic field measurements of the FIELDS instrument on the Parker Solar Probe (PSP) have shown intensities, throughout its first solar encounter, that require a very low source surface (SS) height ( ${R}_{\mathrm{SS}}\leqslant 1.8\,{R}_{\odot }$ ) to be reconciled with magnetic field measurements at the Sun via potential field extrapolation (…