After days of anticipation, many folks won't get to see the northern lights. Here's why.
- This week's forecast for seeing the northern lights across the US was hopeful, but it's now unlikely.
- Original forecasts predicted the lights reaching across 17 US states as far south as Maryland.
Disappointed? You're not alone.
Predictions for a stunning display of the northern lights across the continental US this week were promising, but forecasters say it's unlikely now.
"This one got blown out of proportion a bit," Bill Murtagh, the program coordinator at the National Oceanic and Atmospheric Administration's Space Weather Prediction Center, told USA TODAY.
Earlier this week, news outlets reported that a solar storm would reach Earth, enhancing viewings of the northern lights — also known as aurora borealis — across the US.
Experts predicted the aurora borealis would be most visible on Thursday and could be seen in Midwestern and Western states, reaching as low as Annapolis, Maryland, according to USA TODAY.
But now, those forecasts are much bleaker. Few — if any — US states will be able to see the northern lights. Part of the problem is how unpredictable space weather is.
"There are so many uncertainties, it makes it difficult to predict," Murtagh told USA Today. And as hard as it is to forecast weather here on Earth, "we are decades behind the forecast capabilities of our colleagues in meteorology," he said, referring to space weather.
That's because the aurora starts with the sun, which is notoriously tempermental and difficult to predict.
The sun is constantly emitting a stream of electrically and magnetically charged particles, called the solar wind. This wind washes over Earth, where our planet's magnetic fields funnel it to the poles. There, the solar particles interact with molecules in our atmosphere to create the dancing lights of the aurora.
Usually the northern lights are only visible north of the continental US, in snowy Arctic regions. But when plasma erupts from the surface of the sun, or a "hole" opens in the sun's outer atmosphere, it can accelerate the solar wind and add a flood of fresh particles to the regular stream. When these "solar storms" inundate Earth, they can drive especially vibrant, dancy aurora and push the phenomenon farther south.
The sun has been especially active lately, as it builds toward the peak of its 11-year cycle. That brought the aurora as far south as Arizona in March, making it visible in far more states than forecasters had predicted.
Scientists rely on observations of space and solar activity in order to forecast the northern lights, but things can change quickly. Even in the days and hours leading to a possible appearance of the northern lights, it's still difficult to predict them.
Now, based on the sun's rotation and other factors, NOAA's Space Weather Prediction Center isn't forecasting any significant auroral activity for the continental US states this week.