NASA Logo, External Link
Facebook icon, External Link to NASA STI page on Facebook Twitter icon, External Link to NASA STI on Twitter YouTube icon, External Link to NASA STI Channel on YouTube RSS icon, External Link to New NASA STI RSS Feed AddThis share icon
 

Record Details

Record 1 of 1
Supra Arcade Downflows in the Earth's Magnetotail
NTRS Full-Text: Click to View  [PDF Size: 8.5 MB]
Author and Affiliation:
Kobelski, Adam(West Virginia Univ., Dept. of Physics and Astronomy, Morgantown, WV, United States)
Savage, Sabrina L.(NASA Marshall Space Flight Center, Huntsville, AL, United States)
Malaspina, David M.(Colorado Univ., Laboratory for Atmospheric and Space Physics, Boulder, CO, United States)
Abstract: Pinpointing the location of a single reconnection event in the corona is difficult due to observational constraints, although features directly resulting from this rapid reconfiguration of the field lines can be observed beyond the reconnection site. One set of such features are outflows in the form of post-reconnection loops, which have been linked to observations of supra-arcade downflows (SADs). SADs appear as sunward-traveling, density-depleted regions above flare arcades that develop during long duration eruptions. The limitations of remote sensing methods inherently results in ambiguities regarding the interpretation of SAD formation. Of particular interest is how these features are related to post-reconnection retracting magnetic field lines. In planetary magnetospheres, similar events to solar flares occur in the form of substorms, where reconnection in the anti-sunward tail of the magnetosphere causes field lines to retract toward the planet. Using data from the Time History of Events and Macroscopic Interactions during Substorms (THEMIS), we compare one particular aspect of substorms, dipolarization fronts, to SADs. Dipolarization fronts are observed as rapid but temporary changes in the magnetic field of the magnetotail plasma sheet into a more potential-like dipolar shape. These dipolarization fronts are believed to be retracting post-reconnection field lines. We combine data sets to show that the while the densities and magnetic fields involved vary greatly between the regimes, the plasma betas and Alfvén speeds are similar. These similarities allow direct comparison between the retracting field lines and their accompanying wakes of rarified plasma observed with THEMIS around the Earth to the observed morphological density depletions visible with XRT and AIA on the Sun. These results are an important source of feedback for models of coronal current sheets.
Publication Date: Dec 11, 2017
Document ID:
20170011704
(Acquired Dec 21, 2017)
Subject Category: GEOPHYSICS
Report/Patent Number: MSFC-E-DAA-TN49725
Document Type: Oral/Visual Presentation
Publication Information: (SEE 20170005201)
Meeting Information: American Geophysical Union (AGU) Fall Meeting; 11-15 Dec. 2017; New Orleans, LA; United States
Meeting Sponsor: American Geophysical Union; Washington, DC, United States
Contract/Grant/Task Num: NNM11AA01A
Financial Sponsor: NASA Marshall Space Flight Center; Huntsville, AL, United States
Organization Source: NASA Marshall Space Flight Center; Huntsville, AL, United States
Description: 1p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright; Portions of the document may include copyright protected material
NASA Terms: GEOMAGNETIC TAIL; SUN; CURRENT SHEETS; SOLAR CORONA; MAGNETIC STORMS; MAGNETIC FIELD RECONNECTION; EARTH MAGNETOSPHERE; CORONAL LOOPS; FRONTS (METEOROLOGY); POLAR REGIONS; SOLAR FLARES; LIGHT CURVE; DEPLETION; ELECTRON ENERGY; VELOCITY DISTRIBUTION
› Back to Top
Find Similar Records
NASA Logo, External Link
NASA Official: Gerald Steeman
Site Curator: STI Program
Last Modified: December 21, 2017
Contact Us