Auroras could light up New Year’s skies after solar explosion

Auroras could light up New Year’s skies after solar explosion

Megan Bartels Edited by Lee Billings

The sun is bidding farewell to 2024 with a bang or a few bangs. Our star produced three powerful flares on December 29th. What’s more, the two bubbles of matter sent hurtling across space might dye Earth’s skies with aurora borealis, just as many Earthlings celebrate the turn of the year.

Solar flares are classified by their peak brightness at X-ray wavelengths, with X-class flares being the most intense flashes. Our star’s Dec. 29 activity included three such flares, at 2:18 a.m., 11:14 p.m., and 11:31 p.m. ET, according to a NASA statement. It is said that it has occurred. The outburst represents a continuing disruption in what scientists have identified as the maximum in the sun’s current cycle of activity, which also produced stunning aurora borealis as far south as Florida in May and October.

The Sun’s 11-year cycle is determined by the magnetic fields that shake the star’s surface. “Our sun is a huge magnet, so most of what happens on the sun is guided by magnetism,” says Maria Kazachenko, a solar physicist at the University of Colorado Boulder and the National Solar Observatory.

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Scientists measure the sun’s activity by counting the dark sunspots that mar the sun’s surface. Each sunspot has a smaller magnetic field, but the sunspot itself is often the same size as Earth. Sudden changes in the configuration of a sunspot’s magnetic field, called magnetic reconnection, can release large amounts of energy and cause solar flares. But scientists are still trying to figure out what events can cause magnetic reconnection.

“The main problem with these flares is that you can’t actually put thermometers or magnetometers inside the solar flare,” Kazachenko said. “So it’s very difficult to understand what’s going on.”

And magnetic reconnection at one sunspot, even one far away, can cause what scientists call a “sympathetic eruption.” “We often see flares occurring in clusters,” Kazachenko said. The two flares that occurred Sunday evening represented one such group, including sunspots on opposite sides of the sun’s equator that erupted less than 20 minutes apart.

However, a flare is simply an explosion of radiation. Typically, for an aurora to occur, the sun must emit bubbles of plasma. Scientists call this a coronal mass ejection (CME). This phenomenon follows some, but not all, flares. Whether a CME occurs depends on the details of the magnetic influence. In some flares, magnetic fields trap material within the Sun. Other times, huge clumps of plasma can escape from the flailing star. And the more material there is, Kazachenko says, the more spectacular auroras are likely to occur.

For Sunday’s activity, all three major flares generated CMEs. It is not yet clear whether auroras will occur. However, the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center announced that it will be monitoring geomagnetic storms on December 31st and January 1st, which could result in aurora borealis being visible across the northern and midwestern United States. It is said that there is.

Forecast uncertainty is caused by several factors. With only two CMEs on a potential path to impact Earth, these could still deliver a glancing blow, complicating predictions about their secondary effects. Additionally, Kazachenko says that for an aurora to form, the magnetic field of a clump of plasma must be aligned oppositely to the Earth’s own magnetic field. Otherwise, the plasma would just flow and cause little disruption to Earth.

The recent activity comes as no surprise to scientists who have been closely monitoring the progress of the sun’s activity cycle. At a press conference in October, experts announced that the sun is officially at the maximum of its cycle and will remain so for most of 2025.

“We expect the maximum period to be longer, about three to four years,” Lisa Upton, a solar scientist at the Southwest Research Institute, said at a briefing. “We’re now about two years into the peak, so we expect the peak to last another year or so before we actually enter a downturn.”

Scientists expect increased activity and increased impact on Earth during the remainder of solar maximum and beyond. “We expect additional solar and geomagnetic storms to lead to opportunities to spot auroras in the coming months,” NASA scientist Kelly Kollek said at the same press conference.

And while the sun’s explosion could damage satellites and astronauts in orbit, as well as power grids on Earth, scientists are predicting activity in 2024 and a huge new solar telescope and two Delighted to see activity this solar cycle coinciding with the arrival of separate spacecraft. All of this is designed to uncover the mysteries of how the sun works.

“It’s been a great year,” Kazachenko says. “We are now living through this solar maximum, and now we have a huge array of instruments to observe the sun in new ways. We are now in the golden age of solar multimessenger astronomy. I am alive.”