magnetosphere Archives - Page 2 of 2 - Astrobiology

The UVS instrument recorded spatial information produced by hydrogen atoms radiating from the Earth. In the background a number of individual stars are identified along with the Pleiades star cluster. Juice-UVS plans to similarly observe hydrogen atoms radiating from Ganymede and Jupiter’s other icy moons. Credit Southwest Research Institute

Callisto, Europa, Ganymede, Icy Worlds, Jupiter, Missions & Hardware, Press Release

Astrobiology Fleet Update: ESA Juice Tests SwRI Ultraviolet Spectrograph

by Keith CowingOctober 9, 2024October 9, 2024

As European Space Agency (ESA)’s Jupiter Icy Moons Explorer (Juice) spacecraft hurtled past the Moon and Earth in mid-August to provide its first gravity assist maneuver to the Jovian system, […]

An illustration showing the trajectory of ESA’s Juice spacecraft during its lunar-Earth gravity assist, featuring a high-resolution ENA image of the million-degree hot plasma halo encircling Earth captured by NASA’s JENI instrument. The white rings denote equatorial distance of 4 and 6 Earth radii. The inset showcases measurements taken by the NASA’s JENI and JoEE instruments during their passage through the radiation belts, revealing a highly structured energetic ion and electron environment. Credit: ESA/NASA/Johns Hopkins APL/Josh Diaz

Gaia - Planetary Perspectives, Jupiter, Magnetic Fields, Electromagnetism, bioelectricity,, Missions & Hardware, Press Release, Radiation, Space Weather & Heliophysics

NASA Instruments On ESA Juice Astrobiology Probe Image Earth’s Radiation Belt

by Keith CowingOctober 2, 2024October 2, 2024

From Aug. 19-20, ESA’s (European Space Agency’s) Juice (Jupiter Icy Moons Explorer) mission made history with a daring lunar-Earth flyby and double gravity assist maneuver, a spaceflight first. As the […]

Calibrated images of Ganymede’s 630.0 nm auroral emission displayed in 20 R contours. To better reveal the spatial variability we smoothed the data using a Gaussian kernel with a FWHM of 0. ′′5 approximating typical seeing conditions for the morning of 2021-06-08 UTC. The time in the upper left of each image is the UTC time at the start of the observation, the annotation in the lower right is the distance to the plasma sheet centrifugal equator; positive when Ganymede is above the mid-plane and negative when it is below. As Ganymede moved vertically through the plasma sheet, the hemisphere closest to the mid-plane exhibited the brightest aurora. From approximately 14:00 to 14:45 UTC, Ganymede is within ±0.5 RJ and the brightness is more evenly-distributed across the disk. Ganymede passed through the highestdensity plasma mid-plane at 14:20 UTC, so the top two rows display data when Ganymede was above the mid-plane (with enhanced brightness at southern latitudes) and the bottom row displays data when Ganymede was below the mid-plane (with enhanced brightness at northern latitudes). Because of the blurring effect of atmospheric seeing, the calibrated brightness distribution of the individual pixels is lower than the disk-averaged value reported in de Kleer et al. (2023) and table 1, which assume all emission originates from a disk with Ganymede’s solid-angular size. The white grid shows the physical size and orientation of Ganymede, with north pointing upward (for more details on this observing geometry, see figure 2). -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Ganymede, Icy Worlds, Jupiter, Space Weather & Heliophysics, Status Report, Water/Hycean Worlds & Oceanography

Short-Timescale Spatial Variability of Ganymede’s Optical Aurora

by Keith CowingSeptember 11, 2024September 11, 2024

Ganymede’s aurora are the product of complex interactions between its intrinsic magnetosphere and the surrounding Jovian plasma environment and can be used to derive both atmospheric composition and density.

Sketch of the magnetospheric interaction in the starplanet system Proxima - Proxima b. The stellar wind velocity and the interplanetary magnetic field (IMF) streamlines (assumed to be radial–see text in Sect. 3) are drawn in green and red, respectively. Note that there are magnetic field lines from the star (yellow circle) that are connected to the exoplanet Proxima b (purple circle). The density distribution is shown as a color scale, normalized to the value of the stellar wind density, ρsw = µmpnsw (see Table 1). The sketch represents a super-Alfvénic case, where the ram pressure of the wind dominates over the stellar wind magnetic field pressure, so a bow shock is formed at the dayside of the planet. The Proxima star is beyond the limits of our simulation domain. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biophysics, Exoplanets, -moons, -comets, Habitable Zones, Magnetic Fields, Electromagnetism, bioelectricity,, Proxima Centauri, Radiation, Space Weather & Heliophysics, Status Report

MHD Simulations of the Space Weather in Proxima b: Habitability Conditions and Radio Emission

by Keith CowingMay 30, 2024May 30, 2024

The habitability of exoplanets hosted by M-dwarf stars dramatically depends on their space weather. We present 3D magneto-hydrodynamic simulations to characterise the magneto-plasma environment and thus the habitability of the […]

JADE in situ and UVS remote observations made during PJ16N. (a) UV false color image of the auroral emissions observed close to Ganymede’s footprint. The Juno footpath and the instantaneous footprints of the Galilean moons derived using the JRM33+CON2020 models are shown as red lines and orange dots, respectively. The boundary of the time window over which the UVS data has been co-added is shown at the bottom right corner, and is reported on the Juno footpath as two red dots. The white triangles and crosses along the Juno footpath highlight Juno’s instantaneous footprints with a 10 and 2 minutes time step, respectively. (b) Electron differential number flux measured by JADE-E. The EF is superimposed. (c) Pitch angle distribution. The size of the loss cones at the time of the flux tube crossing is indicated by the dashed line. (d) Arbitrary brightness related to the number of UVS total countrate, UVS false color along the footpath of Juno and electron characteristic energy. The information related to the position of Juno are indicated below the panel (d). The times for the flux tubes crossings estimated from JRM33+CON2020 are represented by vertical gray lines in panels (b, c, d). Events associated with a Ganymede’s flux tube crossing are highlighted by an orange rectangle while the crossing of the main oval is displayed, in panels (b, c, d), as a purple rectangle. -- astro-ph.EP

Ganymede, Jupiter, Magnetic Fields, Electromagnetism, bioelectricity,, Missions & Hardware, Space Weather & Heliophysics, Status Report

Properties of Electrons Accelerated by the Ganymede-magnetosphere Interaction: Survey of Juno High-latitude Observations

by Keith CowingMay 7, 2024

The encounter between the Jovian co-rotating plasma and Ganymede gives rise to electromagnetic waves that propagate along the magnetic field lines and accelerate particles by resonant or non-resonant wave-particle interaction. […]

(a) Time-Energy-Differential Number Flux (DNF) spectrogram of the JADE-E data recorded during Juno’s 12th perijove. (b) Magnetic projection of Juno’s position onto the orbital plane of the Galilean moons (green curves) and Juno’s M-Shell (red curves) calculated with JRM33+KK2005 (dashed lines) and JRM33+CON2020 (plain lines). Vertical blue lines at 09:15:42 and 09:20:46 highlight the magnetic flux tubes crossings of Europa and Io, respectively. Juno’s position and velocity with respect to Jupiter are indicated below the sub-panel (b). -- astro-ph.EP

Callisto, Europa, Ganymede, Io, Jupiter, Status Report

Influence Of The Jovian Current Sheet Models On The Mapping Of The UV Auroral Footprints Of Io, Europa, And Ganymede

by Keith CowingJanuary 19, 2024January 19, 2024

The in-situ characterization of moon-magnetosphere interactions at Jupiter and the mapping of moon auroral footpaths require accurate global models of the magnetospheric magnetic field.

Poynting flux divergence in (a) the bow shock nose and (b) magnetopause reconnection regions. Simulation with southward IMF orientation, |B|IMF = 30 nT and Pd = 1.2 nPa. Black lines indicate the region of the bow shock (n > 20 cm−3 ), the red lines the exoplanet magnetic field lines and the pink iso-surface the reconnection region in the XZ plane (|B| < 5 nT). -- -astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biophysics, Exoplanets, -moons, -comets, Habitable Zones, Radiation, Space Weather & Heliophysics, Water/Hycean Worlds & Oceanography

MHD Study Of Extreme Space Weather Conditions For Exoplanets With Earth-like Magnetospheres: On Habitability Conditions And Radio-emission

by Keith CowingApril 18, 2023April 27, 2023

The present study aims at characterizing the habitability conditions of exoplanets with an Earth-like magnetosphere inside the habitable zone of M stars and F stars like tau Boo, caused by […]