The Sun is a magnetized star. Its magnetic field is essentially three dimensional and it occupies all layers of the solar atmosphere. However, routine measurements of the solar magnetic field have only been achieved at the photospheric level, or the solar surface.
Lacking precise knowledge about the magnetic field in the outermost solar atmosphere, the corona, has impeded our understanding of the solar magnetism and many phenomena in the solar atmosphere.
An international team led by TIAN Hui, a professor from both Peking University and National Astronomical Observatories of Chinese Academy of Sciences (NAOC), has measured the global magnetic field of the solar corona for the first time. The study was published in Science in August 2020.
The team used observations from the Coronal Multi-channel Polarimeter (CoMP), an instrument operated by the High Altitude Observatory, National Center for Atmospheric Research, USA.
More than 20 years ago, a technique called coronal seismology or magneto-seismology has been introduced for coronal magnetic field measurements. This method makes use of some types of oscillations or waves that are observed in coronal structures.
However, these oscillations/waves are just occasionally observed in small regions of the corona, and thus their potential for magnetic field measurements is limited.
CoMP is a coronagraph with a 20-cm (8-in) aperture. It can observe the solar corona using the Fe XIII 1074.7 nm and 1079.8 nm infrared spectral lines. The Doppler image sequence obtained from CoMP observations often reveal the prevalence of propagating periodic disturbances, indicating the ubiquitous presence of transverse plasma waves in the corona.
The team applied the magneto-seismology method to these pervasive waves. They extended the previously developed wave-tracking technique to the whole field of view, and obtained the distribution of the wave propagation speed in the global corona.
They also obtained a global map of the coronal density from observations of the two Fe XIII lines. Combing the maps of wave propagation speed and density, they mapped the magnetic field in the global corona.
“By applying this technique to CoMP-like instruments in the future, global coronal magnetic field maps could be routinely obtained, filling in the missing part of the measurements of the Sun’s global magnetism,” said Prof. TIAN.
Such measurements could provide critical information to advance our understanding of the physical mechanisms responsible for solar eruptions and the 11-year sunspot cycle.
For more on this research, read:
- Solar Physicists Measure Global Magnetic Field of the Solar Corona for the First Time
- Global Magnetic Field of the Solar Corona Mapped for the First Time
Reference: “Global maps of the magnetic field in the solar corona” by Zihao Yang, Christian Bethge, Hui Tian, Steven Tomczyk, Richard Morton, Giulio Del Zanna, Scott W. McIntosh, Bidya Binay Karak, Sarah Gibson, Tanmoy Samanta, Jiansen He, Yajie Chen and Linghua Wang, 7 August 2020, Science.
DOI: 10.1126/science.abb4462
Never miss a breakthrough: Join the SciTechDaily newsletter.
Follow us on Google and Google News.
1 Comment
Greetings to each and every one througout the magna magnetic dust particles throughout the cosmology of dispersal of and in the alpha numeral linguistic utter.
This day time line 26. ,the alpha bets.
O9 the numeral
20 male female 2 binary 0 the family evolution revolution.
20 the quantum geo mechanics.geophydics etc.
I was in prayer supplication EG the breath in a breathing.thr ultimate absolute Omni ALLNESS.
This courage came on my phone .
I am sharing.
.
Now presently the cleansed all you and I EG the baptism of the planetarian allness.eg the whole earth was covered in water.
We having a bath and being fresh.
The gender you and I .to science spirituality civilzation male female EG father mother child
EG 0 13 26 52 thereon to the magna attraction ultimate absolute.
The Cosmo geo corona in virtuity.
This magna magnetic time line is the purity evolution cleansing to know the yoked evolution which was always present.the irridescent colours of magnetic dust particles
This now is the dispersal as Cosmo planetarian storms.
We all must be peaceful relax. Be calm.
The awakening in every pore and hair follicle to energise the nerve ends to nerve ends .
The magnetic energy.
God the Omni divine in all divinity in our being.
Courage the magna magnetic Souls in the normal.
You and I
2000. 3000 the millenium AWAKENING
From written time to greater knowledge of time line
The purity continuity in sanity hble.
GOD BLESS YOU
This was Couraged to all in 1998 to 2002.