(NEW YORK) -- The Northern Lights may be visible as far south as Pennsylvania and Iowa on Friday, Space Weather Prediction Center from the National Oceanic and Atmospheric Administration said.
The remarkable sky lights may come down farther south due to a geomagnetic storm that began on Wednesday, experts said.
The storm is the result of a coronal mass ejection, or CME, which is a powerful burst of magnetized plasma from the sun’s corona, its outermost layer.
Scientists detected two CMEs erupting on the sun and aimed for Earth, which they expected to arrive on August 18.
The CMEs can combine to create a geomagnetic storm, scientists say, to reach strong levels that may create auroras closer to the equator than usual.
The auroras, which make up what we know as the Northern Lights, form when high-energy particles from the sun collide with Earth’s atmosphere. The particles glow because they excite the gasses in the sky.
Stronger energy brings the glowing particles farther from the poles, experts say.
Leading up to the stronger storm, scientists said a coronal hole high-speed stream arrived on Thursday night to create a more minor geomagnetic storm.
A coronal hole is a cooler area in the sun’s outermost layer that can generate high-speed solar wind that is full of charged particles that can get spread across the solar system.
These high-speed streams can create auroras on Earth, too.
Typically, auroras are most visible from December to February, but viewers have strong chances from September to November, too, experts say.
Stronger solar weather is needed for such a view in the summer months.
Alaska is known as a top U.S. destination for seeing the lights, but visitors can also expect a view in northern Maine during favorable conditions, scientists say.
Experts say that less densely populated areas, where the night sky remains darkest, are most favorable for northern viewing of the magical sky lights.