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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,351 records · Page 75
All sourcesNASA NTRSDOE OSTI
NASA NTRS2024

Connecting the Low to High Corona: Propagating Disturbances as Tracers of the Near-Sun Solar Wind

We revisit a quiet 14 day period of solar minimum during 2008 January and track substreamer propagating disturbances (PDs) from low heights in STEREO/EUVI to the extended corona through STEREO/COR1 and into STEREO/COR2 along nonradial paths that trace the structure of the underlying streamers. Using our recently developed method for generating nonradial height–time profiles of outward PDs (OPDs) and inward PDs (IPDs), we obtained their velocities along the radial and position angle directions. Our analysis of 417 unique OPDs revealed two classes: slow and fast OPDs. Slow OPDs form preferentially at ≈1.6 Re closer to the streamer boundaries, with asymmetric occurrence rates, and show speeds of -+ - 16.4 km s 8.4 26.6 1 at 1.5 Re and accelerate up to- + - 200.1 km s 57.9 71.1 1 at 7.5 Re. Fast OPDs form preferentially at ≈1.6 Re and at ≈3.0 Re both at the streamer boundaries and slightly more often within them. They show speeds of - + - 87.8 km s 24.8 59.1 1 at 1.5 Re up to -+ - 197.8 km s 46.7 61.8 1 at 7.5 Re. IPDs are observed forming at ≈1.8 Re with speeds of tens of kilometers per second, mostly concentrated in the aftermath of a coronal mass ejection eruption. We present an example in which we show that periodic brightness variations related to OPDs remained in the range of 98 to 128 minutes, down to ≈2.0 Re, well within the field of view of COR1. The velocity profiles of slow OPDs for a heliocentric height below 3.0 Re show good agreement with speeds more closely related to the bulk solar wind obtained via interplanetary scintillation.

Astronomical techniques↗
DOE OSTI2013

Soft Sun Cells

Representing the Argonne-Northwestern Solar Energy Research (ANSER) Center, this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE: energy. The mission of ANSER is to revolutionize our understanding of molecules, materials and methods necessary to create dramatically more efficient technologies for solar fuels and electricity production.

14 SOLAR ENERGY↗
DOE OSTI2021

SERENA: Particle Instrument Suite for Determining the Sun-Mercury Interaction from BepiColombo

The ESA-JAXA BepiColombo mission to Mercury will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric particle dynamics at Mercury as well as their interactions with solar wind, solar radiation, and interplanetary dust. The particle instrument suite SERENA (Search for Exospheric Refilling and Emitted Natural Abundances) is flying in space on-board the BepiColombo Mercury Planetary Orbiter (MPO) and is the only instrument for ion and neutral particle detection aboard the MPO. It comprises four independent sensors: ELENA for neutral particle flow detection, Strofio for neutral gas detection, PICAM for planetary ions observations, and MIPA, mostly for solar wind ion measurements. SERENA is managed by a System Control Unit located inside the ELENA box. In the present paper the scientific goals of this suite are described, and then the four units are detailed, as well as their major features and calibration results. Finally, the SERENA operational activities are shown during the orbital path around Mercury, with also some reference to the activities planned during the long cruise phase.

79 ASTRONOMY AND ASTROPHYSICS↗