Japanese satellite Hinode discovers two huge holes in sun’s magnetic field
A Japanese satellite has captured images showing two huge holes in the Sun’s outer atmosphere, the solar corona, which are blasting solar material into space.
Known as “coronal holes” these openings in the Sun’s magnetic field allow gas to escape into space through the star’s super-hot outer atmosphere where they become the “solar wind”.
But don’t worry, experts say the holes don’t pose a threat to the Earth.
Associate Professor Mike Wheatland from the University of Sydney said effects we see back on Earth are caused more by other solar activity.
“While these are quite beautiful pictures we are unlikely to see any effects from the holes back on Earth,” Dr Wheatland said.
“That sort of thing is caused more by solar flares.”
The solar storm of 1859 was triggered by a large solar flare and created auroras which were seen around the world, it also played havoc with communications with telegraph systems failing and reports of some operators being shocked.
There are also reports of some systems appearing to send and receive messages even after being disconnected from their power supplies.
Dr Wheatland said coronal holes are associated with the quiet, steady solar wind, which is always flowing out from the Sun.
Events like enhanced aurorae and interruptions to radio communication are associated with solar activity, consisting of short dynamic events such as solar flares and coronal mass ejections.
The X-ray images, taken by Japan’s sun-watching satellite Hinode on February 1, clearly show two large dark holes at the top and the bottom of the Sun.
“The holes are relatively cool in temperature as compared to the active regions nearby,” NASA officials said in a statement.
“The cooler temperature is one of the reasons for the darker appearance.”
The discovery of the holes may help scientists close in on the mystery of why the Sun’s atmosphere, or “corona”, is millions of degrees hotter than its surface.
Although usually invisible to the naked eye you can see the corona as a white halo of superhot gas around the Sun during a solar eclipse.
Japan’s Hinode solar observatory has been studying the Sun and its activity since the spacecraft was launched in 2006.
Its studies are designed to help “improve our understanding of the mechanisms that power the solar atmosphere and drive solar eruptions” and has been instrumental in several key discoveries including identifying the origin of the white light emission in solar flares last year.
The mission is a collaborative mission between NASA and the space agencies of Japan, the United Kingdom, Norway and Europe and Japan’s National Astronomical Observatory.