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Solar jets are well-collimated plasma ejections in the solar atmosphere. They are prevalent in active regions, the quiet Sun, and even coronal holes. They display a range of temperatures, yet the nature of the cool components has not been fully investigated. In this paper, we show the existence of the precursors and quasi-periodic properties for two chromospheric jets, mainly utilizing the He I 10 830 Å narrowband filtergrams taken by the Goode Solar Telescope (GST). The extreme ultraviolet (EUV) counterparts present during the eruption correspond to a blowout jet (jet 1) and a standard jet (jet 2), as observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO). The high-resolution He I 10 830 Å observation captures a long-lasting precursor for jet 1, signified by a series of cool ejections. They are recurrent jet-like features with a quasi-period of about five minutes. On the other hand, the cool components of jet 2, recurrently accompanied by EUV emissions, present a quasi-periodic behavior with a period of about five minutes. Both the EUV brightening and He I 10 830 Å absorption show that there was a precursor for jet 2 that occurred about five minutes before its onset. We propose that the precursor of jet 1 may be the consequence of chromospheric shock waves, since the five-minute oscillation from the photosphere can leak into the chromosphere and develop into shocks. Then, we find that the quasi-periodic behavior of the cool components of jet 2 may be related to magnetic reconnections modulated by the oscillation in the photosphere.
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This content will become publicly available on August 1, 2025
Solar Jet Hunter: A citizen science initiative to identify and characterize coronal jets at 304 Å
Context.Solar coronal jets seen in extreme ultraviolet (EUV) are ubiquitous on the Sun, and they have been found in and at the edges of active regions, at the boundaries of coronal holes, and in the quiet Sun. Jets have various shapes, sizes, brightness, velocities, and durations in time, which complicates their detection by automated algorithms. So far, solar jets reported in the Heliophysics Event Knowledgebase (HEK) have been mostly reported by humans looking for them in the data, with different levels of precision regarding their timing and positions. Aims.We created a catalog of solar jets observed in EUV at 304 Å containing precise and consistent information on the jet timing, position, and extent. Methods.We designed a citizen science project, Solar Jet Hunter, on the Zooniverse platform, to analyze EUV observations at 304 Å from the Solar Dynamic Observatory/Atmospheric Imaging Assembly (SDO/AIA). We created movie strips for regions of the Sun in which jets have been reported in HEK and ask the volunteers to 1) confirm the presence of at least one jet in the data and 2) report the timing, position, and extent of the jet. Results.We report here the design of the project and the results obtained after the analysis of data from 2011 to 2016. We note that 365 “coronal jet” events from HEK served as input for the citizen science project, equivalent to more than 120 000 images distributed into 9689 “movie strips”. Classification by the citizen scientists resulted in 883 individual jets being identified. Conclusions.We demonstrate how citizen science can enhance the analysis of solar data with the example of Solar Jet Hunter. The catalog of jets thusly created is publicly available and will enable statistical studies of jets and related phenomena. This catalog will also be used as a training set for machines to learn to recognize jets in further datasets.
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- Award ID(s):
- 1752268
- PAR ID:
- 10564674
- Publisher / Repository:
- Astronomy and Astrophysics
- Date Published:
- Journal Name:
- Astronomy & Astrophysics
- Volume:
- 688
- ISSN:
- 0004-6361
- Page Range / eLocation ID:
- A127
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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