Solar Flare Blackouts: Understanding the Impact A powerful X-class solar flare recently hit the Earth, causing radio blackouts across various regions. Here's what you need to know:
What Happened? - The solar flare was classified as X2.7, making it the strongest flare of 2025 so far. - It was emitted by sunspot region 4087, which has a complex magnetic field posing a continued threat for X-class flares. - The flare caused radio blackouts over southeast Asia, Europe, and the Middle East due to increased X-ray and extreme ultraviolet radiation.
Effects on Earth - *Radio Blackouts*: High-frequency radio signals were disrupted or completely absorbed, impacting communication systems. - *No Significant CME Impact*: Fortunately, the coronal mass ejection (CME) associated with this flare is not expected to collide with Earth. - *Potential for Future Flares*: Sunspot region 4087 may release more solar flares and CMEs, potentially affecting Earth in the coming days.¹ ²
Understanding Solar Flares - *Classification*: Solar flares are ranked on a scale from B to X, with each letter representing a ten-fold increase in energy output. - *Impact*: X-class flares can cause significant disruptions to communication systems and pose a risk to astronauts in space.³
Staying Informed - *Space Weather Prediction Center*: Monitor their forecasts and updates for the latest information on solar flares and their potential impact on Earth. - *Aurora Alerts*: Stay tuned for potential aurora sightings, which can occur when CMEs interact with Earth's magnetic field.
00:00As we approached the solar cycle's apex in 2024, the sun had a very active year, bringing us numerous solar storms.
00:08But our star is not done quite yet, and has hurled another strong solar flare into the solar system from sunspot region 4087.
00:16In terms of magnitude, the solar flare was classed as an X 2.7 flare.
00:22The smallest of flares are B-class, followed by C, M, and the strongest category, X, while the numbers following the letter also denote strength within that category.
00:33C-class flares are too weak to noticeably affect Earth.
00:37M-class flares can cause brief radio blackouts at the poles and minor radiation storms that might endanger astronauts.
00:44Although X is the last letter, there are flares more than 10 times the power of an X1, so X-class flares can go higher than 9.
00:53The coronal material from that ejection is unlikely to hit Earth, with NASA models expecting it to hit Mercury and graze Venus.
01:01However, shortly thereafter, an M-class solar flare occurred, and a portion of it may have collided with Earth, possibly bringing aurora with it.
01:10The X 2.7 flare, released at 8.25 a.m. universal time coordinated on May 14th, is not expected to have produced a CME that will collide with Earth, according to the NOAA Space Weather Prediction Center.
01:24Flares of this magnitude are not frequent.
01:27They note, adding, users of high frequency, HF.
01:30Radio signals may experience temporary degradation or complete loss of signal on much of the sunlit side of Earth.
01:37Even though astronomers can warn us about CMEs, because the material can take anywhere from a few hours to several days to reach our planet,
01:45we only see flares when their effects hit the Earth.
01:48This can include interference with radio waves.
01:51According to the Space Weather Prediction Center,
01:54ionization in the lower layers of the ionosphere on the sunlit side of Earth results from the increased level of X-ray and extreme ultraviolet, EUV, radiation.
02:04Under normal conditions, high frequency, HF, radio waves are able to support communication over long distances by refraction via the upper layers of the ionosphere.
02:15When a strong enough solar flare occurs, ionization is produced in the lower, more dense layers of the ionosphere, the D-layer,
02:24and radio waves that interact with electrons in layers lose energy due to the more frequent collisions that occur in the higher density environment of the D-layer.
02:33This can cause HF radio signals to become degraded or completely absorbed.
02:38This results in a radio blackout, the absence of HF communication, primarily impacting the 3 to 30 MHz band.
02:47Sunspot Region 4087 unleashed a smaller flare yesterday, though it was still notably large at Category X 1.2,
02:55causing a brief shortwave radio blackout in the Americas, according to SpaceWeather.com.
03:00That flare was associated with a coronal mass ejection, CME, large expulsions of plasma and magnetic field from the sun's corona.
03:09Additionally, it is accountable for accelerating the precipitation of energetic protons into the atmosphere of Earth,
03:16resulting in a low S1, class radiation storm warning.
03:20At this level, there is no risk to biological life, though radio can be affected.
03:25At this level, there is no risk to biological life, though radio can be affected.
