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Updated: Jul 9, 2026
06:27
Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer
Published on: May 29, 2019
Ultraviolet observations of solar fine structure
Science (New York, N.Y.)
|November 27, 1987
Summary
High Resolution Telescope and Spectrograph observations reveal solar macrospicule dynamics. The study found transition zone emission originates from fine, subresolution structures less than 70 km wide.
Area of Science:
- Solar Physics
- Astronomy
- Space Science
Background:
- The solar chromosphere and transition zone are dynamic regions crucial for understanding solar activity.
- Previous observations lacked the spatial and temporal resolution to resolve fine structures within these layers.
Purpose of the Study:
- To investigate the temporal development of macrospicules at the solar limb.
- To determine the characteristic scales of emission structures in the C IV transition zone.
Main Methods:
- Utilized the High Resolution Telescope and Spectrograph (HRTS) instrument.
- Conducted extended observations during the Spacelab-2 shuttle mission.
- Analyzed ultraviolet spectroheliograms to capture high spatial and temporal resolution data.
Main Results:
- Observed the temporal evolution of macrospicules at the solar limb.
- Identified discrete emission elements within the C IV transition zone.
- Determined these elements are composed of subresolution structures smaller than 70 kilometers.
Conclusions:
- Macrospicules exhibit dynamic behavior at the solar limb.
- The C IV transition zone emission is not uniform but originates from very fine, unresolved structures.
- These findings provide new insights into the microphysics of the solar atmosphere.
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