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The utility of polarized heliospheric imaging for space weather monitoring.

DeForest CE, Howard TA, Webb DF, Davies JA - Space Weather (2016)

Bottom Line: Recent advances in heliospheric imaging have demonstrated that a polarized imager is feasible with current component technology.Developing this technology to a high technology readiness level is critical for space weather relevant imaging from either a near-Earth or deep-space mission.We consider deployment as an instrument on NOAA's Deep Space Climate Observatory follow-on near the Sun-Earth L1 Lagrange point, as a stand-alone constellation of smallsats in low Earth orbit, or as an instrument located at the Sun-Earth L5 Lagrange point.The critical first step is the demonstration of the technology, in either a science or prototype operational mission context.

View Article: PubMed Central - PubMed

Affiliation: Department of Space Studies Southwest Research Institute Boulder Colorado USA.

ABSTRACT

A polarizing heliospheric imager is a critical next generation tool for space weather monitoring and prediction. Heliospheric imagers can track coronal mass ejections (CMEs) as they cross the solar system, using sunlight scattered by electrons in the CME. This tracking has been demonstrated to improve the forecasting of impact probability and arrival time for Earth-directed CMEs. Polarized imaging allows locating CMEs in three dimensions from a single vantage point. Recent advances in heliospheric imaging have demonstrated that a polarized imager is feasible with current component technology.Developing this technology to a high technology readiness level is critical for space weather relevant imaging from either a near-Earth or deep-space mission. In this primarily technical review, we developpreliminary hardware requirements for a space weather polarizing heliospheric imager system and outline possible ways to flight qualify and ultimately deploy the technology operationally on upcoming specific missions. We consider deployment as an instrument on NOAA's Deep Space Climate Observatory follow-on near the Sun-Earth L1 Lagrange point, as a stand-alone constellation of smallsats in low Earth orbit, or as an instrument located at the Sun-Earth L5 Lagrange point. The critical first step is the demonstration of the technology, in either a science or prototype operational mission context.

No MeSH data available.


Related in: MedlinePlus

Polarization profiles of individual features at different locations reveal the exit angle of the feature relative to the Thomson surface (Figure 3). (left) Each curve shows the polarization fraction of a feature seen at a particular apparent distance (elongation) ϵ from the Sun versus the angle from the plane of the sky. (right) For a given polarization fraction, two trajectories are possible. One is correct, and the other is obviously nonphysical [DeForest et al., 2013a]. This enables unambiguous location of space weather relevant disturbances in 3‐D.
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swe20300-fig-0004: Polarization profiles of individual features at different locations reveal the exit angle of the feature relative to the Thomson surface (Figure 3). (left) Each curve shows the polarization fraction of a feature seen at a particular apparent distance (elongation) ϵ from the Sun versus the angle from the plane of the sky. (right) For a given polarization fraction, two trajectories are possible. One is correct, and the other is obviously nonphysical [DeForest et al., 2013a]. This enables unambiguous location of space weather relevant disturbances in 3‐D.

Mentions: pB/B ratios have been used by a very few authors to locate structures observed with coronagraphs [e.g., Mierla et al., 2010, and references therein; de Koning and Pizzo, 2011], but determinations in the corona are subject to a front/back ambiguity [e.g., DeForest et al., 2013a]. The wider field of view provided by heliospheric imagers breaks the front/back ambiguity. This occurs because solar wind features propagate approximately radially. Of the two possible paths for a sequence of pB/B measurements of a feature in the heliosphere, one path is approximately radial and the other is highly nonphysical (Figure 4). It is worth reiterating that this symmetry breaking is only achievable because heliospheric imagers observe across a large angular range in the sky.


The utility of polarized heliospheric imaging for space weather monitoring.

DeForest CE, Howard TA, Webb DF, Davies JA - Space Weather (2016)

Polarization profiles of individual features at different locations reveal the exit angle of the feature relative to the Thomson surface (Figure 3). (left) Each curve shows the polarization fraction of a feature seen at a particular apparent distance (elongation) ϵ from the Sun versus the angle from the plane of the sky. (right) For a given polarization fraction, two trajectories are possible. One is correct, and the other is obviously nonphysical [DeForest et al., 2013a]. This enables unambiguous location of space weather relevant disturbances in 3‐D.
© Copyright Policy - creativeCommonsBy-nc-nd
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4933095&req=5

swe20300-fig-0004: Polarization profiles of individual features at different locations reveal the exit angle of the feature relative to the Thomson surface (Figure 3). (left) Each curve shows the polarization fraction of a feature seen at a particular apparent distance (elongation) ϵ from the Sun versus the angle from the plane of the sky. (right) For a given polarization fraction, two trajectories are possible. One is correct, and the other is obviously nonphysical [DeForest et al., 2013a]. This enables unambiguous location of space weather relevant disturbances in 3‐D.
Mentions: pB/B ratios have been used by a very few authors to locate structures observed with coronagraphs [e.g., Mierla et al., 2010, and references therein; de Koning and Pizzo, 2011], but determinations in the corona are subject to a front/back ambiguity [e.g., DeForest et al., 2013a]. The wider field of view provided by heliospheric imagers breaks the front/back ambiguity. This occurs because solar wind features propagate approximately radially. Of the two possible paths for a sequence of pB/B measurements of a feature in the heliosphere, one path is approximately radial and the other is highly nonphysical (Figure 4). It is worth reiterating that this symmetry breaking is only achievable because heliospheric imagers observe across a large angular range in the sky.

Bottom Line: Recent advances in heliospheric imaging have demonstrated that a polarized imager is feasible with current component technology.Developing this technology to a high technology readiness level is critical for space weather relevant imaging from either a near-Earth or deep-space mission.We consider deployment as an instrument on NOAA's Deep Space Climate Observatory follow-on near the Sun-Earth L1 Lagrange point, as a stand-alone constellation of smallsats in low Earth orbit, or as an instrument located at the Sun-Earth L5 Lagrange point.The critical first step is the demonstration of the technology, in either a science or prototype operational mission context.

View Article: PubMed Central - PubMed

Affiliation: Department of Space Studies Southwest Research Institute Boulder Colorado USA.

ABSTRACT

A polarizing heliospheric imager is a critical next generation tool for space weather monitoring and prediction. Heliospheric imagers can track coronal mass ejections (CMEs) as they cross the solar system, using sunlight scattered by electrons in the CME. This tracking has been demonstrated to improve the forecasting of impact probability and arrival time for Earth-directed CMEs. Polarized imaging allows locating CMEs in three dimensions from a single vantage point. Recent advances in heliospheric imaging have demonstrated that a polarized imager is feasible with current component technology.Developing this technology to a high technology readiness level is critical for space weather relevant imaging from either a near-Earth or deep-space mission. In this primarily technical review, we developpreliminary hardware requirements for a space weather polarizing heliospheric imager system and outline possible ways to flight qualify and ultimately deploy the technology operationally on upcoming specific missions. We consider deployment as an instrument on NOAA's Deep Space Climate Observatory follow-on near the Sun-Earth L1 Lagrange point, as a stand-alone constellation of smallsats in low Earth orbit, or as an instrument located at the Sun-Earth L5 Lagrange point. The critical first step is the demonstration of the technology, in either a science or prototype operational mission context.

No MeSH data available.


Related in: MedlinePlus