This weekend, skywatchers in parts of the United States and Canada are in for a rare and breathtaking treat as the Northern Lights, or Aurora Borealis, are expected to make a grand appearance.
Thanks to heightened solar activity, including a series of coronal mass ejections (CMEs) from the Sun, the National Oceanic and Atmospheric Administration (NOAA) has issued a geomagnetic storm watch that could bring the Northern Lights far south of their usual range, offering a spectacular celestial show to millions of people.
The Science Behind the Northern Lights
The Northern Lights are one of the most beautiful and awe-inspiring natural phenomena on Earth. They occur when charged particles from the Sun, primarily electrons, collide with gases in Earth's atmosphere. These particles are funneled toward the polar regions by Earth's magnetic field, where they interact with nitrogen and oxygen in the atmosphere, creating the vivid colors of the aurora. The colors—ranging from green to pink to violet—depend on the type of gas involved and the altitude at which the interaction occurs.
The intensity and visibility of the Northern Lights are closely tied to solar activity, particularly events known as coronal mass ejections. CMEs are massive bursts of solar wind and magnetic fields released into space from the Sun’s atmosphere. When these CMEs reach Earth, they can compress the planet’s magnetosphere, triggering geomagnetic storms that intensify the Northern Lights.
The storms push the auroras further from the poles, making them visible at lower latitudes than usual. This weekend, a G2 (moderate) geomagnetic storm is expected, which could extend the visibility of the auroras into the continental United States.
Where and When to See the Northern Lights
The upcoming geomagnetic storm has the potential to make the Northern Lights visible across a broad swath of the northern United States, including states like Washington, Idaho, Montana, North Dakota, South Dakota, Minnesota, Wisconsin, Michigan, and as far east as New York and Maine. Residents of Canada and Alaska will also have prime viewing opportunities, with the auroras expected to be especially vivid in these regions.
For the best chance of witnessing this natural spectacle, it’s recommended to be as far north as possible and away from sources of light pollution, such as city lights. The auroras are typically most visible between 10 p.m. and 2 a.m. local time, but this window can vary depending on your location and the strength of the geomagnetic storm. To maximize your chances, it’s advisable to keep an eye on real-time space weather updates from sources like NOAA’s Space Weather Prediction Center, which provides current data on auroral activity and viewing conditions.
Thursday night offers a preview of the weekend's celestial show, with the aurora potentially visible across parts of Canada and Alaska, and in some northern U.S. states. As the weekend progresses, the geomagnetic activity is expected to intensify, making the auroras brighter and more widespread.
The Impact of Solar Cycle 25 on Aurora Activity
The heightened activity that is driving this weekend’s Northern Lights display is part of a larger trend tied to Solar Cycle 25. Solar cycles last about 11 years and are marked by periods of increased and decreased solar activity. The current cycle began in December 2019 and is expected to peak between late 2024 and early 2026. During this peak, known as the solar maximum, the number of sunspots—dark, cooler areas on the Sun’s surface—reaches its highest point, leading to more frequent and intense solar phenomena like solar flares and CMEs.
Solar Cycle 25 has been busier than scientists initially anticipated, with more sunspots and solar activity than predicted. This increase in solar activity has already resulted in several powerful geomagnetic storms this year, pushing the Northern Lights into view in areas where they are rarely seen. As the solar maximum approaches, we can expect more opportunities to witness such events, making this an exciting time for both amateur and professional astronomers.
The effects of Solar Cycle 25 are not just limited to the Northern Lights. Increased solar activity can also impact satellite operations, GPS systems, and even power grids on Earth, highlighting the broader significance of these solar phenomena. For now, though, the focus is on the spectacular light shows they produce in the night sky.
The Perseid Meteor Shower: An Added Bonus
While the Northern Lights are certainly the main event this weekend, they won’t be the only spectacle in the night sky. The Perseid meteor shower, one of the most popular and reliable meteor showers of the year, is also set to peak between Sunday night and Monday morning. During its peak, skywatchers can expect to see up to 100 meteors per hour under ideal conditions.
The Perseids are known for their bright, fast-moving meteors, which often leave long, glowing trails in their wake. This year, the meteor shower will be enhanced by the presence of the Northern Lights, creating a truly extraordinary viewing experience. Even in the days leading up to the peak, the Perseid meteors will be visible, with increasing frequency as the weekend progresses.
For those lucky enough to be in the right place at the right time, this weekend offers a rare opportunity to witness two of nature’s most stunning displays—Northern Lights and meteors—lighting up the sky together. Whether you’re an experienced astronomer or a casual stargazer, it’s a show you won’t want to miss.