The solar wind is a ubiquitous feature of our solar system. This relentless high-speed flow of charged particles from the sun fills interplanetary space. On Earth, it triggers geomagnetic storms that can disrupt satellites and it causes the dazzling auroras — the northern and southern lights — at high latitudes.
However, precisely how the sun generates the solar wind has remained unclear. New observations by the Solar Orbiter spacecraft might provide an answer.
Researchers on Thursday said that the spacecraft has detected numerous relatively small jets of charged particles expelled intermittently from the corona — the sun’s outer atmosphere — at supersonic speeds for 20 to 100 seconds.
Photo: Reuters / ESA & NASA / Solar Orbiter / EUI team
The jets emanate from structures on the corona called coronal holes where the sun’s magnetic field stretches into space rather than back into the star. They are called “picoflare jets” due to their relatively small size. They arise from areas a few hundred kilometers wide — tiny when compared to the immense scale of the sun, which has a diameter of 1.4 million kilometers.
“We suggest that these jets could actually be a major source of mass and energy to sustain the solar wind,” said solar physicist Lakshmi Pradeep Chitta from the Max Planck Institute for Solar System Research in Germany, lead author of the research published in the journal Science.
The solar wind consists of plasma — ionized gas, or gas in which the atoms lose their electrons — and is mostly ionized hydrogen.
“Unlike the wind on Earth that circulates the globe, solar wind is ejected outward into interplanetary space,” Chitta said.
“Earth and the other planets in the solar system whiz through the solar wind as they orbit around the sun. Earth’s magnetic field and atmosphere act as shields and protects life by blocking harmful particles and radiation from the sun, but the solar wind continuously propagates outward from the sun and inflates a plasma bubble called the heliosphere that encompasses the planets,” Chitta added.
The heliosphere extends out to about 100 to 120 times further than Earth’s distance to the sun.
The data for the study were obtained last year by one of the three telescopes on an instrument called the Extreme Ultraviolet Imager aboard the Solar Orbiter, a sun-observing probe built by the European Space Agency and NASA that was launched in 2020. The Solar Orbiter was about 50 million kilometers from the sun at the time — about one-third of the distance separating the sun and Earth.
“This finding is important, as it sheds more light on the physical mechanism of the solar wind generation,” said solar physicist and study coauthor Andrei Zhukov of the Royal Observatory of Belgium.
The solar wind’s existence was predicted by American physicist Eugene Parker in the 1950s and was verified in the 1960s.
“Still, the origin of the solar wind remains a longstanding puzzle in astrophysics,” Chitta said. “A key challenge is to identify the dominant physical process that powers the solar wind.”
The Solar Orbiter is discovering new details about the solar wind and is expected to obtain even better data in the coming years using additional instruments and viewing the sun from other angles.
Zhukov said stellar wind is a phenomenon common to most, if not all, stars, though the physical mechanism might differ among various types of stars.
“Our understanding of the sun is much more detailed than the understanding of other stars, due to its proximity and thus the possibility to make more detailed observations,” Zhukov added.
A fire caused by a burst gas pipe yesterday spread to several homes and sent a fireball soaring into the sky outside Malaysia’s largest city, injuring more than 100 people. The towering inferno near a gas station in Putra Heights outside Kuala Lumpur was visible for kilometers and lasted for several hours. It happened during a public holiday as Muslims, who are the majority in Malaysia, celebrate the second day of Eid al-Fitr. National oil company Petronas said the fire started at one of its gas pipelines at 8:10am and the affected pipeline was later isolated. Disaster management officials said shutting the
DITCH TACTICS: Kenyan officers were on their way to rescue Haitian police stuck in a ditch suspected to have been deliberately dug by Haitian gang members A Kenyan policeman deployed in Haiti has gone missing after violent gangs attacked a group of officers on a rescue mission, a UN-backed multinational security mission said in a statement yesterday. The Kenyan officers on Tuesday were on their way to rescue Haitian police stuck in a ditch “suspected to have been deliberately dug by gangs,” the statement said, adding that “specialized teams have been deployed” to search for the missing officer. Local media outlets in Haiti reported that the officer had been killed and videos of a lifeless man clothed in Kenyan uniform were shared on social media. Gang violence has left
US Vice President J.D. Vance on Friday accused Denmark of not having done enough to protect Greenland, when he visited the strategically placed and resource-rich Danish territory coveted by US President Donald Trump. Vance made his comment during a trip to the Pituffik Space Base in northwestern Greenland, a visit viewed by Copenhagen and Nuuk as a provocation. “Our message to Denmark is very simple: You have not done a good job by the people of Greenland,” Vance told a news conference. “You have under-invested in the people of Greenland, and you have under-invested in the security architecture of this
Japan unveiled a plan on Thursday to evacuate around 120,000 residents and tourists from its southern islets near Taiwan within six days in the event of an “emergency”. The plan was put together as “the security situation surrounding our nation grows severe” and with an “emergency” in mind, the government’s crisis management office said. Exactly what that emergency might be was left unspecified in the plan but it envisages the evacuation of around 120,000 people in five Japanese islets close to Taiwan. China claims Taiwan as part of its territory and has stepped up military pressure in recent years, including
RSS