A giant sunspot on the far side of the Sun will face Earth this weekend, potentially wreaking havoc on our planet with a geomagnetic storm.
The spot is so big that it changes the way Sun vibrates, according to spaceweather.com. When the dark spot throws up a clot of plasma Earth, it could disrupt our magnetic field and affect GPS and communications satellites in low-Earth orbits, as well as aircraft navigation systems. The National Oceanic and Atmospheric Administration (NOAA) Space Weather Forecast Center issued a forecast on August 6-7 for a choppy geomagnetic field around the Earth, which could mean auroras, although it’s not yet clear if it will turn into a full-blown solar storm.
Sunspots are dark spots on the sun’s surface caused by strong magnetic fields. While this sunspot is on the other side of the Sun, scientists have discovered it by monitoring its effects on the Sun’s vibrations.
“The sun is constantly vibrating because of convection bubbles hitting the surface,” Dean Pesnell, project scientist at NASA’s Solar Dynamics Observatory (SDO), told Live Science in an email. Hot and cool bubbles that continuously rise and fall in the Sun move energy and cause vibrations that can be detected by solar observatories like the SDO. The sunspot’s strong magnetic field slows these oscillations traveling through the sun. As a result, observatories like the SDO can monitor sunspots on the far side of our host star by delaying these vibrational waves, even though they can only see the near side, Pesnell added.
“The larger the sunspot and the stronger the magnetic field, the greater this lag will be,” Pesnell said.
The telltale vibrational changes were revealed on a helioseismic map near the Sun’s southeastern limb.
This weekend, the sunspot will turn toward Earth, which could potentially cause it solar flares — an intense burst of radiation in the solar atmosphere.
“We’ll likely see flares as the sunspot comes into view,” Pesnell said.
This solar activity could affect the Earth. Solar flares can heat clouds of electrically charged particles from the Sun’s upper atmosphere to tremendous temperatures that can hurl gigantic blobs of plasma toward Earth, known as coronal mass ejections (CMEs). “There’s a filament going towards the sunspot, and so there might be some coronal mass ejections,” Pesnell added.
“Solar flares and CMEs are the most important effects of solar activity on Earth,” Pesnell said. “According to my work, higher solar activity means increased drag on satellites orbiting near Earth — and satellite operators will lose revenue if that drag knocks a functioning satellite out of orbit.” Communications and navigation in the polar regions – often used by intercontinental plane flights – and even power outages on Earth.
The Sun has an 11-year cycle in which its activity waxes and wanes, with a distinct “solar maximum” and “solar minimum” when the number of sunspots is greatest and least numerous, respectively. The sun is now heading for a solar maximum in 2024 or 2025. The sun has been like this lately more active than NASA predicted. CMEs are normal behavior for sunspots at this point in the sunspot cycle, Pesnell said.
Originally published on Live Science.
Huge, potentially disruptive sunspot will swing round to face Earth this weekend Source link Huge, potentially disruptive sunspot will swing round to face Earth this weekend