Table of Contents¶
In the following chapters, we’ll cover examples from active research. Each chapter provides the motivation for the research and all of the code necessary to reproduce the results of a paper published in a peer-reviewed scientific journal. These chapters cover a variety of topics, but they all employ machine learning methods to heliophysics, which includes the study of the Sun and its effects on our solar system – the Earth, planets, minor objects, and all of the space in between.
Below is a short summary of each chapter. Each summary gives a brief overview of the machine learning methods and data types involved in solving a specific research problem. Each “>” symbol is designed to drill down from a general idea into a specific one. If some of these terms don’t make sense, don’t worry! Acronyms are defined at the bottom and the chapters explain each scientific and machine learning concept in detail.
About This Book¶
Author(s): James Paul Mason
Objective: Fit time series measurements of solar ultraviolet light to contrast new and familiar concepts
ML method(s) and concepts:
Preprocessing > data cleaning > imputing (sklearn.preprocessing.Imputer)
Model selection > splitting data into training and validation sets > shuffle split (sklearn.model_selection.ShuffleSplit)
Regression > support vector machine > support vector regression (sklearn.svm.SVR)
Model selection > determining best performing model > validation curve (sklearn.model_selection.validation_curve)
Data source(s):
Solar spectral irradiance > extreme ultraviolet light > extracted emission line time series > SDO/EVE
Chapter 1¶
Author(s): Monica Bobra
Objective: Predict solar flares (outbursts of high energy light) and coronal mass ejections (outbursts of particles) based on measurements of the sun’s surface magnetic field
ML method(s) and concepts:
Classification > support vector machine > support vector classifier (sklearn.svm.svc)
Model selection > splitting data into training and validation sets > stratified k-folds (sklearn.model_selection.StratifiedKFold)
Data sources(s):
Solar surface magnetic field (AKA magnetograms) > SDO/HMI
Solar spectral irradiance > soft x-ray light > extracted flare peak intensity and time > GOES/XRS flare event database
Solar disk-blocked coronal images > visible light > extracted ejection occurrence and time > SOHO/LASCO and STEREO/SECCHI/COR coronal mass ejection database
Published and refereed paper: Bobra & Ilonidis, 2016, Astrophysical Journal, 821, 127
Chapter 2¶
Author(s): Carlos José Díaz Baso and Andrés Asensio Ramos
Objective: Rapid and robust image resolution enhancement
ML method(s) and concepts:
Data source(s):
Solar surface magnetic field (AKA magnetograms) > SDO/HMI
Solar surface images > visible light > SDO/HMI
Solar surface images > visible light > Hinode/SOT
Published and refereed paper: Díaz Baso & Asensio Ramos, 2018, Astronomy & Astrophysics, 614, A5
Chapter 3¶
Author(s): Paul Wright, Mark Cheung, Rajat Thomas, Richard Galvez, Alexandre Szenicer, Meng Jin, Andrés Muñoz-Jaramillo, and David Fouhey
Objective: Simulating data from a lost instrument (EVE) based on another of a totally different type (AIA¹³)
ML method(s) and concepts:
Image transformation > mapping > convolutional neural networks (pytorch)
Model selection > determining model performance > mean squared error loss (torch.nn.MSELoss)
Data source(s):
Solar spectral images > extreme ultraviolet light > SDO/AIA
Solar spectral irradiance > extreme ultraviolet light > extracted emission line time series > SDO/EVE
Published and refereed paper: Szenicer A. et al., 2019, Science Advances , 5, 10
Chapter 4¶
Author(s): Ryan M. McGranaghan, Anthony Mannucci, Brian Wilson, Chris Mattmann, Richard Chadwick
Objective: Predicting high-latitude ionospheric scintillation
ML method(s) and concepts:
Model selection > splitting data into training and validation sets > random (sklearn.model_selection.train_test_split)
Classification > support vector machine > support vector classifier (sklearn.svm.svc)
Dimensionality reduction > feature selection > Fisher ranking score (Gu et al. 2011)
Data source(s):
Solar wind > magnetic field strength and direction > ACE, Wind, IMP 8, and Geotail
Solar wind > velocity and pressure > ACE, Wind, IMP 8, and Geotail
Aurora > electrojets > various ground-based polar observatories complied by Kyoto WDCG
Geomagnetic field > symmetric disturbances > various ground-based polar observatories complied by Kyoto WDCG
Ionosphere > total electron content > GISTM
Ionosphere > radio spectrum > GISTM
Ionosphere > scintillation > GISTM
Published and refereed paper: McGranaghan et al., 2018, Space Weather, 16, 11
Chapter 5¶
Author(s): Brandon Panos, Lucia Kleint, Cedric Huwyler, Säm Krucker, Martin Melchior, Denis Ullmann, Sviatoslav Voloshynovskiy
Objective: Analyzing the behavior of a single spectral line (MgII) across many different flaring active regions
ML method(s) and concepts:
Clustering > K-means
Data source(s):
Solar spectral data > ultraviolet light > IRIS
Published and refereed paper: Panos et al., 2018, Astrophysical Journal, 861, 1
Chapter 6¶
Author(s): Tobías Felipe and Andrés Asensio Ramos
Objective: Detection of far-side active regions
ML method(s) and concepts:
Image transformation > mapping > convolutional neural networks (pytorch)
Model selection > determining model performance > binary cross-entropy (torch.nn.BCELoss)
Data source(s):
Solar surface magnetic field (AKA magnetograms) > SDO/HMI
Solar far-side seismic maps > SDO/HMI
Published and refereed paper: Felipe & Asensio Ramos, 2019, Astronomy & Astrophysics, 632, A82
Chapter 7¶
Author(s): Colin Small, Matthew R. Argall, Marek Petrik
Objective: Automated detection of magnetopause crossings
ML method(s) and concepts:
Classification > recurrent neural network > long short-term memory (tf.keras.layers.LSTM)
Data source(s):
Electron diffusion region > magnetopause > magnetic field strength and direction > MMS
Electron diffusion region > magnetopause > velocity and pressure > MMS
Published and refereed paper: Argall, Small, et al., 2020, Front. Astron. Space Sci., 7
Chapter 8¶
Author(s): Rafael Pires de Lima and Yue Chen
Objective: Forecast relativistic electrons in Earth’s Outer Radiation Belt
ML method(s) and concepts:
Preprocessing > data management > splitting data into training, validation, and test sets
Regression > linear regression (sklearn.linear_model.LinearRegression)
Regression > convolutional neural networks (TensorFlow)
Model evaluation > determining best performing model > validation curve (sklearn.model_selection.validation_curve)
Data source(s):
Geomagnetic disturbance index Dst and upstream solar wind conditions > OMNI
Measurements from low-Earth-orbit satellite POES-15 for electrons with different energies > POES
1 MeV electrons measurements > RBSP
Published and refereed paper: Pires de Lima et al., 2020, Space Weather, 18, 2
Chapter 9¶
Author(s): Téo Bloch, Clare Watt, Mathew Owens, Leland McInnes & Allan R. Macneil
Objective: Characterising the latent structure in the solar wind to determine the solar source regions.
ML method(s) and concepts:
Preprocessing > data management > splitting data into training, science sets
Unsupervised machine learning > Clustering > Bayesian Gaussian Mixture model (sklearn.mixture.BayesianGaussianMixture)
Unsupervised machine learning > Clustering > HDBSCAN (hdbscan.hdbscan_.HDBSCAN)
Unsupervised machine learning > Dimension Reduction > UMAP (umap.umap_.UMAP)
Data source(s):
Solar wind data > Ulysses and ACE
Published and refereed paper: Bloch et al., 2020, Solar Physics, 295, 41
Future Chapters¶
Contact us! Open an issue on the GitHub repository with your idea. See our guide for contributing here.
Definitions¶
ACE: Advanced Composition Explorer
AIA: Atmospheric Imaging Assembly onboard SDO
COR: Coronagraph onboard STEREO
EVE: Extreme Ultraviolet Variability Experiment onboard SDO
GISTM: Global Navigation Satellite System Ionospheric Scintillation and Total Electron Content Measurements Monitor
GOES: Geostationary Operational Environmental Satellites
HDBSCAN: Hierarchical Density-Based Spatial Clustering of Applications with Noise
HMI: Helioseismic Magnetic Imager onboard SDO’
IRIS: Iterface Region Imaging Spectrograph
Irradiance is the total output of light from the sun. Spectral irradiance is that intensity as a function of wavelength.
LASCO: Large Angle and Spectrometric Coronagraph onboard SOHO
POES: Polar Operational Environmental Satellites
RBSP: Radiation Belt Storm Probes
MMS: Magnetospheric MultiScale mission
SDO: Solar Dynamics Observatory
SECCHI: Sun Earth Connection Coronal and Heliospheric Investigation suite of instruments onboard STEREO
SOHO: Solar and Heliospheric Observatory
SOT: Solar Optical Telescope onboard Hinode
STEREO: Solar Terrestrial Relations Observatory
UMAP: Uniform Manifold Approximation and Prediction
WDCG: World Data Center for Geomagnetism
XRS: X-Ray Sensor