The recent news (e.g. WSJ, June 14-15) that the European Space Agency's Solar Orbiter has captured the first ever images of the Sun's south pole was exciting to any solar physicist. That includes the more than 100 researchers assembled at the SDO - 2025 conference I attended in February, e.g.
Their excitement would be understandable given how the prospect of any significant findings - i.e. connected with the solar poles- would almost certainly tie into their own research using the Solar Dynamic Observatory. The range of potential areas ranged from solar inertial modes and their relation to the Sun's differential rotation, to the occurrence of sympathetic flares, and eruptivity of solar flares.
To that end, the ESA's solar spacecraft - like the Solar Dynamic Observatory - represents the ability for us to get observations of the Sun's atmosphere and surface that will help enhance space weather predictions. (Space weather being the term for the near Earth effects of solar eruptions such as associated with coronal mass ejections (CMEs) and solar flares.
Indeed, just last year (May) the Sun erupted in a series of highly energetic solar flares and CMEs that severely disturbed Earth's magnetic field - enough to disrupt GPS-guided tractors used by farmers. The events also intense currents through power grids, overheating transformers. The combined effects also temporarily thickened Earth's atmosphere to the extent several thousand satellites had to adjust their orbits to avoid the drag created by the solar conditions.
On Wednesday two weeks ago the European Space Agency released the first
clear images of the Sun’s south pole, which were captured in late March by its
Solar Orbiter spacecraft. The $550 million (€500 million) Solar Orbiter, the size of a
car and carrying 10 scientific instruments, launched
on Feb. 10, 2020,. In order to get into an orbit that enabled south polar views of the Sun the craft had to fly by Venus multiple times for a "sling shot" effect. In this way Venus' mass could provide the gravitational "kick" needed to escape the Earth's orbital plan (or ecliptic). Thus enabling it to push itself out of the ecliptic plane and into a higher angle to view the Sun's poles. The change in views resulting are pronounced, e.g. compare the view from Earth:
Careful comparison of the two images will show that the lower one - from the Solar Orbiter - has the Sun's south pole slightly tilted upward. This is also confirmed by the slightly more curved solar latitude and longitude lines. (Indicating the Orbiter has by now escaped the orbital plane using the sling shot effect). This then enabled the even more well defined image of the south polar region shown below:
Here, close examination shows tiny jets erupting from the surface, which we call spicules. These are dynamic bursts of solar plasma the origin of which is still being studied by solar physicists. Another more detailed view of intense magnetic effects is shown below:
Look carefully and you will see mixed red and blue areas, also distinguished by intensity. In this case, the darker the color the stronger the magnetic field - which is along the line of sight from the Solar Orbiter to the Sun. The close study of these areas may well unravel the role of the solar dynamo in producing the 11-year and 22 -year solar cycles. See e.g.
And:
Studying the Sun's polar regions should help solar physicists – such as the groups attending the SDO -2025 conference- probe the varying strengths of solar maximums. Being able to anticipate the intensity of each 11-year cycle could warn humanity of the dangers posed to satellites and ground infrastructure from space weather.
By October, scientists will receive views of the north solar
pole that have already been taken by the spacecraft but have yet to be sent to
Earth. Their goal is to look for differences between the two poles. In 2027 and 2029, Solar Orbiter will reach even higher
inclinations, first 24 degrees and then 33 degrees, when the sun is heading
toward solar minimum.
Solar
Orbiter gets world-first views of the Sun’s south pole
We
FINALLY Saw the Sun's South Pole... and It’s Terrifying!
And:
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