PADRE Science Goals & Objectives

PADRE’s Science Goal:

Investigate the dominant electron acceleration mechanisms in large solar flares

“How is the magnetic energy converted into electrons’ kinetic energy during solar flares?”


by determining the degree of beaming of accelerated electrons in large solar flares

But, how?

Implementing Two approaches:

  • by measuring spatially-integrated spectro-polarimetric hard X-rays
  • by coordinating with Solar Orbiter/STIX to make two point measurements of X-rays and determining their directivity.

The Solar PolArization and Directivity X-Ray Experiment (PADRE) represents a pioneering effort in the study of solar flares and the complex dynamics of the Sun’s atmosphere. By employing advanced instrumentation and innovative observational techniques, PADRE aims to address fundamental questions about the acceleration and transport of charged particles during solar eruptive events. This page provides an overview of PADRE’s science goals and objectives, highlighting its significance in advancing our understanding of solar physics.

Understanding Solar Flares:
Solar flares are among the most energetic phenomena in the solar system, releasing vast amounts of energy in the form of electromagnetic radiation and charged particles. These eruptions are driven by the sudden release of magnetic energy stored in the solar corona, but the precise mechanisms underlying flare initiation and particle acceleration remain poorly understood.

Science Goals of PADRE:

1. Acceleration Mechanisms: PADRE aims to unravel the intricate processes involved in the conversion of magnetic energy into kinetic energy during solar flares. By studying the acceleration mechanisms of charged particles, PADRE seeks to elucidate the fundamental physics governing flare dynamics.

2. Angular Distribution of Accelerated Electrons: One of PADRE’s primary objectives is to determine the angular distribution of accelerated electrons within solar flares. By characterizing the spatial and energy-dependent properties of these particles, PADRE aims to shed light on the mechanisms responsible for particle acceleration and transport.

3. Stereoscopic Observations: PADRE will conduct stereoscopic observations of solar flares in coordination with the Solar Orbiter/STIX mission. This innovative approach will provide unprecedented insights into the three-dimensional structure of flare-accelerated particle populations, allowing for detailed analysis of particle trajectories and energy distributions.

Experimental Approach:
PADRE utilizes a 12U CubeSat observatory equipped with state-of-the-art x-ray spectro-polarimetric instrumentation. The observatory will observe the Sun in hard X-rays (HXRs) from low Earth orbit, enabling high-resolution measurements of flare emissions across a wide range of energies.

Key Scientific Questions:

– How is magnetic energy stored in the solar corona converted into kinetic energy during a solar flare?
– What is the angular distribution of accelerated electrons within solar flares, and how does it vary with energy and spatial location?
– What are the primary acceleration mechanisms responsible for driving solar eruptive events, and how do they contribute to flare dynamics?