In a study published recently in the journal Nature Astronomy, researchers have unveiled the discovery of extreme wave energy from a reasonably cool, dark and highly magnetized plasma area on the Sun, capable of passing through the solar atmosphere and keeping temperature levels of a million degrees Kelvin inside the corona.
Extreme ultra-violet emission by solar coronal plasma at millions of degrees. Credit: Atmospheric Imaging Assembly (AIA) on board NASAs Solar Dynamics Observatory (SDO) spacecraft
Scientists say the finding is the most recent key to unwinding a host of associated secrets relating to Earths nearest star.
” The coronal heating problem is one of the most significant secrets in solar physics research. It has existed for nearly a century,” stated Wenda Cao, BBSO director and NJIT physics professor who is co-author of the study. “With this study, we have fresh answers to this problem, which might be key to untangling lots of complicated questions in energy transport and dissipation in the solar atmosphere, in addition to the nature of area weather condition.”
Using GSTs special imaging capabilities, the group led by Yuan Ding had the ability to initially capture transverse oscillations in the darkest and coldest region on the Sun, called the sunspot umbra.
Such dark sunspot regions can form as the stars strong magnetic field reduces thermal conduction and prevents the energy supply from the hotter interior to the noticeable surface area (or photosphere), where temperature levels reach approximately 5,000 degrees Celsius.
A video showing high-resolution observations of transverse movement in the sunspot. Credit: NJIT-BBSO, Yuan et al., Nature Astronomy, 2023
To investigate, the team determined activity associated to many dark features detected in an active sunspot recorded on July 14, 2015, by BBSOs GST– consisting of oscillatory transverse motions of plasma fibrils within the sunspot umbra in which the electromagnetic field is more than 6,000 times more powerful than that of Earths.
” Fibrils appear as cone-shaped structures with a common height of 500-1,000 km and a width of about 100 km,” described Vasyl Yurchyshyn, NJIT-CSTR research study professor of heliophysics and BBSO senior researcher. “Their life time varies from two to three minutes and they tend to reappear at the same area within the darkest parts of the umbra, where magnetic fields are greatest.”
” These dark vibrant fibrils had actually been observed in the sunspot umbra for a long time, but for the first time, our group was able to detect their lateral oscillations that are manifestations of fast waves,” stated Cao. “These persistent and ubiquitous transverse waves in strongly magnetized fibrils bring energy upwards through vertically lengthened magnetic avenues and add to the heating of the upper atmosphere of the Sun.”
Anatomy of our Sun. Credit: ESA
Through a mathematical simulation of these waves, the group approximates the energy brought could be as much as thousands times more powerful than energy losses in active area plasma of the Suns upper environment– dissipating energy up to 4 orders of magnitude more powerful than the heating rate required to maintain the blazing plasma temperatures in the corona.
” Various waves have been spotted everywhere on the Sun, but generally their energy is too low to be able to heat up the corona,” stated Yurchyshyn. “The fast waves found in the sunspot umbra are a efficient and consistent energy source that may be responsible for heating up the corona above sunspots.”
In the meantime, researchers state the new findings not only reinvent our view of the sunspot umbra, but use another important action in advancing physicists understanding of the energy transportation procedures and heating of the solar corona.
Questions about the coronal heating issue persist.
” While these findings are a step forward toward resolving the mystery, the energy flux coming out of sunspots may be only accountable for heating those loops that are rooted in sunspots,” stated Cao. “Meanwhile, there are other sunspot-free areas related to hot coronal loops that still wait for to be described. We expect that GST/BBSO will continue supplying the highest-resolution observational proof to additional unlock secrets of our star.”
Reference: “Transverse oscillations and an energy source in a highly allured sunspot” by Ding Yuan, Libo Fu, Wenda Cao, Błażej Kuźma, Michaël Geeraerts, Juan C. Trelles Arjona, Kris Murawski, Tom Van Doorsselaere, Abhishek K. Srivastava, Yuhu Miao, Song Feng, Xueshang Feng, Carlos Quintero Noda, Basilio Ruiz Cobo and Jiangtao Su, 25 May 2023, Nature Astronomy.DOI: 10.1038/ s41550-023-01973-3.
A brand-new research study using the Goode Solar Telescope at Big Bear Solar Observatory has uncovered extreme wave energy from the sunspot umbra that might keep million-degree temperature levels in the Suns corona. While the finding advances our understanding of the Suns coronal heating issue, the mystery isnt completely resolved yet.
With information from Big Bear Solar Observatorys Goode Solar Telescope, scientists discover intense wave energy in the coldest region on the Sun, the sunspot umbra, which is driving puzzling temperature levels in the stars upper environment.
Nearly 5 thousand kilometers above the Suns surface area lies a century-old concern for solar physicists– how are temperature levels in the stars upper environment, or corona, numerous times hotter than temperatures at the Suns visible surface area?
A global team of scientists has a new response to the concern– frequently referred to as the Suns coronal heating issue– with brand-new observational information acquired with the 1.6-meter Goode Solar Telescope (GST) at Big Bear Solar Observatory (BBSO), run by NJITs Center for Solar Terrestrial Research (CSTR).
” The coronal heating issue is one of the most significant secrets in solar physics research. “With this research study, we have fresh responses to this issue, which may be essential to untangling numerous complicated concerns in energy transport and dissipation in the solar environment, as well as the nature of area weather.”
” While these findings are a step forward toward solving the mystery, the energy flux coming out of sunspots may be just responsible for heating up those loops that are rooted in sunspots,” said Cao. “Meanwhile, there are other sunspot-free regions associated with hot coronal loops that still await to be described. We expect that GST/BBSO will continue supplying the highest-resolution observational proof to additional unlock mysteries of our star.”
