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Updated: Jul 9, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Small-scale jetlike features in penumbral chromospheres
Y Katsukawa1, T E Berger, K Ichimoto
1National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan. yukio.katsukawa@nao.ac.jp
Science (New York, N.Y.)
|December 8, 2007
Summary
Scientists discovered tiny, fast-moving jets in sunspots called penumbral microjets. These jets, possibly from magnetic reconnection, may heat the solar corona above sunspots.
Area of Science:
- Solar Physics
- Astronomy
- Plasma Physics
Background:
- Sunspots exhibit complex magnetic fields in their penumbrae.
- Chromospheric jets are dynamic phenomena observed in the solar atmosphere.
Purpose of the Study:
- To identify and characterize fine-scale jetlike features in sunspot chromospheres.
- To investigate the origin and potential implications of these microjets.
Main Methods:
- Observation of a sunspot using the Solar Optical Telescope on the Hinode satellite.
- Analysis of image sequences captured through a Ca II H-line filter.
Main Results:
- Discovery of penumbral microjets, characterized by a width of 400 km and duration under 1 minute.
- These features are difficult to detect with existing observational capabilities.
Conclusions:
- Penumbral microjets may originate from magnetic reconnection within the sunspot's complex magnetic field.
- These microjets have the potential to contribute to coronal heating above sunspots.
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