Alin Razvan Paraschiv

WHPI repository of 2024 Total Solar Eclipse activities

whawkins — Tue, 19 Mar 2024 16:14:43 +0000

WHPI repository of 2024 Total Solar Eclipse activities whawkins Tue, 03/19/2024 - 10:14

Author:

whawkins

Mar 19, 2024

HAO is leading the effort through the Whole Heliosphere and Planetary Interactions (WHPI) initiative to support the 2024 Total Solar Eclipse by providing a platform for gathering information on ongoing eclipse activities. The WHPI Eclipse Campaign website aims to be a one-stop repository for existing or ongoing eclipse efforts.

The Total Solar Eclipse on April 8, 2024 offers ideal conditions for eclipse science, unique opportunities for cross-disciplinary collaborations, and an excellent occasion for public engagement. HAO is leading the effort through the Whole Heliosphere and Planetary Interactions (WHPI) initiative to support the 2024 Total Solar Eclipse by providing a platform for gathering information on ongoing eclipse activities. The WHPI Eclipse Campaign website aims to be a one-stop repository for existing or ongoing eclipse efforts. We welcome any and all contributions, no effort is too small! Please contact us at whpi_help@hao.ucar.edu if you have any questions or would like to be included.

The repository is currently:

Linking to model prediction outputs of what to expect on the eclipse day;
Providing information on planned dedicated observations by ground and space-based assets that will pursue and support eclipse science;
Compiling a list of eclipse science experiments that will be deployed on or flown into the eclipse path;
Providing information on Citizen Science projects those interested can join in;
Listing planned outreach and public engagement efforts.

We hope our repository will promote interactions between the different efforts and foster collaboration across disciplines. We wish everyone a clear sky and happy observing of the eclipse!

Annular Eclipse Expedition at Hovenweep

whawkins — Fri, 03 Nov 2023 21:53:04 +0000

Annular Eclipse Expedition at Hovenweep whawkins Fri, 11/03/2023 - 15:53

Author:

whawkins

Nov 3, 2023

The logo that represents all the institutions that made the annular eclipse expedition possible superimposed over the eclipse maxima image.

On 14 October 2023, a captivating annular eclipse graced the skies from Oregon to Texas in the U.S. It was a privilege to not only witness this celestial spectacle but also engage with a curious audience that included a team of solar physicists from both the High Altitude Observatory at NCAR and the National Solar Observatory. Visiting students and/or voluntary collaborators were also among the spectators.

Sunrise and over-imposed eclipse evolution at Hovenweep National Monument in Utah.

Han Uitenbroek

An annular solar eclipse occurs when the Moon passes directly between the Earth and the Sun, but the Moon is too far from Earth to block out the Sun entirely. Instead of a total eclipse, a ring of sunlight is illuminated around the Moon, creating the infamous "Ring of Fire".

Our expedition led us to the historic Hovenweep National Monument in Utah, where, around well-preserved Ancestral Puebloan ruins, we had the opportunity of sharing insights about the Sun! The NPS estimated that over 600 visitors were on site. Favorable weather allowed attendees to experience this remarkable event through an array of telescopes, binoculars, and eclipse glasses.

Photo of the annular eclipse maxima from the eclipse expedition, Hovenweep National Monument.

Han Uitenbroek

Using a colander to create pinhole projections onto paper.

With materials provided by the NASA PUNCH outreach team for the Small Explorer mission, we engaged the public with various activities touching not only on the eclipse science, but also on relevant cultural and historical aspects related to how humans have perceived solar eclipses and other Solar phenomena throughout the centuries, as depicted in paintings, drawings, and petroglyphs.

Some of the images below offer a glimpse into the fascinating natural optical phenomenon of pinhole projection. They illustrate how differently-shaped holes on objects produce shadows that mirror the contour of the light source. This effect becomes especially apparent during an eclipse, resulting in crescents or rings forming within the shadowed area.

Photo collage of observation deck visitors at the annular eclipse expedition, Hovenweep National Monument, UT.

Additionally, our team offered evening astronomy sessions that allowed attendees to explore the beautiful dark skies of Hovenweep. They had the chance to marvel at Saturn's rings, observe the distinctive cloud patterns and moons of Jupiter, witness the splendour of the Andromeda Galaxy, and an array of distant globular clusters and nebulae, providing a rich experience of the wonders above.

Photo collage of outreach table activities at the annular eclipse expedition, Hovenweep National Monument, Utah.

This annular solar eclipse was truly a sight to see, and yet 2024 will provide an even more rare opportunity of a total solar eclipse over the U.S./Canada on April 8th.

We express our gratitude to all attendees for their active participation, to the dedicated team for their unwavering commitment, to the National Parks Service team and to the supporting institutions.

An abundance of stars at Hovenweep National Monument taken during the annular eclipse expedition.

Teams included:

NSO: Alin Paraschiv, Han Uitenbroek
NCAR HAO: Matthias Rempel, Daniela Lacatus, Maurice Wilson, Benoit Tremblay
Students and/or collaborators: Aatiya Ali, Kalista Tyson, Vanessa Mercea, Aidan Halpin

A Machine Learning Enhanced Approach for Automated Sunquake Detection in Acoustic Emission Maps

whawkins — Fri, 16 Dec 2022 19:58:01 +0000

A Machine Learning Enhanced Approach for Automated Sunquake Detection in Acoustic Emission Maps whawkins Fri, 12/16/2022 - 12:58

Author:

whawkins

Dec 16, 2022

Sunquakes are seismic emissions visible on the solar surface, sometimes associated with solar flares. Despite the availability of several manual detection guidelines, to our knowledge, the astrophysical data produced for sunquakes is new to the field ofMachineLearning.

We introduce an acoustic holography processed dataset constructed from egression-power maps of solar active regions for Solar Cycles 23 and 24. We then present a pedagogical approach to the application of machine learning representation methods for sunquake detection using AutoEncoders, Contrastive Learning, Object Detection and recurrent techniques, which we enhance by introducing several custom domain-specific data augmentation transformations.

With our trained models, we find temporal and spatial locations of peculiar acoustic emission and associate them to eruptive and high energy emission in two C1 class flares. While noting that models are still in a prototype stage and there is much room for improvement, we hypothesize that these have potential to first enable routine detection of weak solar acoustic manifestations.

Process diagram of proposed solution. The gray-labeled augmentations represent standard ML approaches, while the others depict custom transforms that were found by us to improve our sunquake prediction model.

Thermal and Non-thermal Properties of Active Region Recurrent Coronal Jets Publication Name

whawkins — Wed, 21 Sep 2022 17:06:04 +0000

Thermal and Non-thermal Properties of Active Region Recurrent Coronal Jets Publication Name whawkins Wed, 09/21/2022 - 11:06

Author:

whawkins

Sep 21, 2022

The Astrophysical Journal: Alin R. Paraschiv, Alina C. Donea, and Philip G. Judge present comprehensive observations of recurrent active region coronal jets, and derive their thermal and non-thermal properties. We discuss a peculiar penumbral magnetic reconnection site, which we previously identified as a "Coronal Geyser". This analysis of geysers provides new information and observational constraints applicable to theoretical modeling of solar jets. The main thermal plasma physical parameters, such as temperature, density, energy flux contributions, etc., are calculated using multiple inversion techniques. The underlying models are assessed, and their limitations and applicability are debated. Additionally, we perform source reconstruction and spectral analysis of higher energy observations to further assess the thermal structure and identify non-thermal plasma emission properties. Cool and hot thermal emission are found. These jets are found to be energetically stronger than polar jets, but we find their potential influence on heliospheric energetics and dynamics to be limited. We additionally found that our observations can only be explained by a combination of thermal and non-thermal emission models.

A multi-wavelength view of a coronal geyser jet.

Predicting the Geoeffectiveness of CMEs Using Machine Learning

whawkins — Tue, 23 Aug 2022 15:59:37 +0000

Predicting the Geoeffectiveness of CMEs Using Machine Learning whawkins Tue, 08/23/2022 - 09:59

Author:

whawkins

Aug 23, 2022

UMAP of the predictions of the ensemble model, applied on the test set (20% of the data), colored by their correctness. Labels: TN - True Negative; FP - False Positive; TP - True Positive; FN - False Negative.

Coronal mass ejections are the most important space weather phenomena, being associated with large geomagnetic storms, and having the potential to cause disturbances to telecommunications, satellite network disruptions, and power grid damage and failures. Thus, considering these storms' potential effects on human activities, accurate forecasts of the geoeffectiveness of CMEs are paramount. This work focuses on experimenting with different machine-learning methods trained on data sets of close-to-Sun CMEs, to estimate whether such a newly erupting ejection has the potential to induce geomagnetic activity. We developed classification models using a variety of machine learning approaches. At this time, we limited our forecast to exclusively use solar onset parameters, to ensure extended warning times. We discuss the main challenges of this task and show that adequate predictions can be achieved with these models.

Optimal spectral lines for measuring chromospheric magnetic fields

kolinski — Mon, 11 Jul 2022 20:33:01 +0000

Optimal spectral lines for measuring chromospheric magnetic fields kolinski Mon, 07/11/2022 - 14:33

Efficient and Automated Inversions of Magnetically-Sensitive Forbidden Coronal Lines: CLEDB - The Coronal Line Emission DataBase Magnetic Field Inversion Algorithm

kolinski — Mon, 11 Jul 2022 20:24:06 +0000

Efficient and Automated Inversions of Magnetically-Sensitive Forbidden Coronal Lines: CLEDB - The Coronal Line Emission DataBase Magnetic Field Inversion Algorithm kolinski Mon, 07/11/2022 - 14:24

Author:

kolinski

Jul 11, 2022

Alin Paraschiv and Philip Judge present CLEDB, a single point inversion algorithm for determining magnetic parameters using spectro-polarimetric measurements of emission lines formed in the solar corona. We select lines of interest and construct databases for combinations of plasma thermal and magnetic configurations. The method is intended to be applied to two or more lines observed simultaneously. The solutions initially yield magnetic orientation, thermal properties, and the spatial position of the emitting plasma in three dimensions. Multiple possible solutions for each observation are returned, including irreducible degeneracies. The magnetic field strength is separately derived from the simple ratio of observed to database polarization data, after the thermal properties and scattering geometry solutions have been determined.

CLEDB 2-line magnetic inversion algorithm flowchart. An important aspect is the delivery of multiple possible solutions for each observation at the last step. Note that the x-coordinate of the point in space, as well as nearest electron density, are returned along with B. The figure uses the notation Vobs and Vdb for observed and computed values of the amplitudes of the Stokes parameters corresponding to O3 and S3 (B = 1) in the text.

A Spectroscopic Survey of Infrared 1–4 μm Spectra in Regions of Prominent Solar Coronal Emission Lines of Fe XIII, Si X, and Si IX

kolinski — Mon, 11 Jul 2022 18:57:40 +0000

A Spectroscopic Survey of Infrared 1–4 μm Spectra in Regions of Prominent Solar Coronal Emission Lines of Fe XIII, Si X, and Si IX kolinski Mon, 07/11/2022 - 12:57

Publication: The Astrophysical Journal; Authors: Aatiya Ali, Alin Razvan Paraschiv, Kevin Reardon, and Philip Judge

Author:

kolinski

Jul 11, 2022

The infrared solar spectrum contains a wealth of physical data about the Sun and is being explored using modern detectors and technology with new ground-based solar telescopes. One such instrument will be the ground-based Cryogenic Near-IR Spectro-Polarimeter of the Daniel K. Inouye Solar Telescope (DKIST), which will be capable of sensitive imaging of the faint infrared solar coronal spectra with full Stokes polarization states. Highly ionized emission lines have been observed in galaxies and the solar corona. Quantifying the accuracy of spectral inversion procedures requires a precise spectroscopic calibration of observations. A careful interpretation of the spectra around prominent magnetic dipole lines is essential for deriving physical parameters and particularly for quantifying the off-limb solar coronal observations from DKIST. In this work, we aim to provide an analysis of the spectral regions around the infrared coronal emission lines of Fe xiii 1074.68 nm, Fe xiii 1079.79 nm, Si x 1430.10 nm, and Si ix 3934.34 nm, aligning with the goal of identifying solar photospheric and telluric lines that will help facilitate production of reliable inversions and data products from four sets of solar coronal observations.

Fe XIII 1074.68 nm emission over atmospheric absorption (normalized) in the He I Cryo-NIRSP wavelength range with all labeled candidate lines. The green curve represents the atmospheric spectra that are convolved with a Gaussian function correspondent to the Cryo-NIRSP 0"5 slit spectral resolution of 0.027 nm.

Alin Razvan Paraschiv

WHPI repository of 2024 Total Solar Eclipse activities

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