Engineering topics

Skoug, R.

Publications and source records attributed to Skoug, R..

3 records

NASA NTRS2018

Interstellar Mapping and Acceleration Probe (IMAP): A New NASA Mission

The Interstellar Mapping and Acceleration Probe (IMAP) is a revolutionary mission that simultaneously investigates two of the most important overarching issues in Heliophysics today: the acceleration of energetic particles and interaction of the solar wind with the local interstellar medium. While seemingly disparate, these are intimately coupled because particles accelerated in the inner heliosphere play critical roles in the outer heliospheric interaction. Selected by NASA in 2018, IMAP is planned to launch in 2024. The IMAP spacecraft is a simple sun-pointed spinner in orbit about the Sun-Earth L1 point. IMAP's ten instruments provide a complete and synergistic set of observations to simultaneously dissect the particle injection and acceleration processes at 1 AU while remotely probing the global heliospheric interaction and its response to particle populations generated by these processes. In situ at 1 AU, IMAP provides detailed observations of solar wind electrons and ions; suprathermal, pickup, and energetic ions; and the interplanetary magnetic field. For the outer heliosphere interaction, IMAP provides advanced global observations of the remote plasma and energetic ions over a broad energy range via energetic neutral atom imaging, and precise observations of interstellar neutral atoms penetrating the heliosphere. Complementary observations of interstellar dust and the ultraviolet glow of interstellar neutrals further deepen the physical understanding from IMAP. IMAP also continuously broadcasts vital real-time space weather observations. Finally, IMAP engages the broader Heliophysics community through a variety of innovative opportunities. This papersummarizes the IMAP mission at the start of Phase A development.

McComas, D. J.↗

NASA NTRS2007

Encounter of the Ulysses Spacecraft with the Ion Tail of Comet McNaught

Comet McNaught was the brightest comet observed from Earth in the last 40 years. For a period of five days in early 2007 February, four instruments on the Ulysses spacecraft directly measured cometary ions and key properties of the interaction of the comet's ion tail with the high-speed solar wind from the polar regions of the Sun. Because of the record-breaking duration of the encounter, the data are unusually comprehensive. O3(+) ions were detected for the first time in a comet tail, coexisting with singly charged molecular ions with masses in the range 28-35 amu. The presence of magnetic turbulence and of ions with energies up to approximately 200 keV indicate that at a distance of approximately 1.6 AU from the comet nucleus, the ion tail McNaught had not yet reached equilibrium with the surrounding solar wind.

plasmas↗

NASA NTRS2005

Dayside Global Ionospheric Response to the Major Interplanetary Events of October 29-30, 2003 ''Halloween Storms''

We demonstrate extreme ionospheric response to the large interplanetary electric fields during the "Halloween" storms that occurred on October 29 and 30, 2003. Within a few (2 - 5) hours of the time when the enhanced interplanetary electric field impinged on the magnetopause, dayside total electron content increases of approx.40% and approx.250% are observed for the October 29 and 30 events, respectively. During the Oct 30 event, approx.900% increases in electron content above the CHAMP satellite (approx.400 km altitude) were observed at mid-latitudes (+/-30 degrees geomagnetic). The geomagnetic storm-time phenomenon of prompt penetration electric fields is a possible contributing cause of these electron content increases, producing dayside ionospheric uplift combined with equatorial plasma diffusion along magnetic field lines to higher latitudes, creating a "daytime super-fountain" effect.

magnetosphere↗