Full Breakdown
Twin X-Class Solar Flares Trigger Radio Blackouts on Earth's Dayside
4/25/2026, 12:25:35 PM
Event Overview: Twin X-Class Flares from AR4419
On the Sun’s western limb, sunspot region AR4419 produced two X-class flares within a seven-hour span. The first flare peaked at 9:07 p.m. EDT on 23 April 2024 (0107 GMT 24 April) and the second at 4:14 a.m. EDT on 24 April (0814 GMT). Sources differ on the exact class of the first flare—one report lists it as X2.5, another as X2.4—while both agree the second flare was X2.5.
Solar Cycle Context
NASA’s Solar Dynamics Observatory and NOAA’s Space Weather Prediction Center note that the Sun follows an approximately 11-year electromagnetic cycle, alternating between solar maximum and minimum. The agencies reported that the Sun entered a roughly year-long solar maximum in October 2024, a phase that has since passed, yet the star continues to generate regular flares, including the April events.
Timeline
- 23 April 2024: Series of M-class flares observed from AR4419.
- 23 April 2024, 9:07 p.m. EDT: First X-class flare (X2.4/X2.5) erupts.
- 23 April 2024: Rare “sympathetic flare” occurs in a separate sunspot region.
- 24 April 2024, 4:14 a.m. EDT: Second X-class flare (X2.5) erupts.
- 24 April 2024: High-frequency radio blackouts reported over the Pacific, Australia, and East Asia.
Data & Statistics
Flare magnitudes: X2.4 (or X2.5) and X2.5. Strongest X-class flares recorded in the preceding 78 days, according to solar physicist Ryan French. Neither flare ranks among the top 50 strongest on record; the most powerful, an X40+ event, occurred on 4 Nov 2003. Associated coronal mass ejections (CMEs) were estimated to travel at ~6 million mph, though their trajectory toward Earth remains uncertain.
Impact on Earth: Radio Blackouts and Potential Geomagnetic Effects
Radiation from the flares ionized the ionosphere’s lower layers, producing high-frequency (HF) radio blackouts on the sunlit side of the planet. The first blackout affected parts of the Pacific Ocean and Australia; the second impacted East Asia. NOAA’s Space Weather Prediction Center warned that a glancing CME could still trigger geomagnetic storm conditions and visible auroras.
Official Statements & Responses
NOAA explained that “when radiation from a solar flare reaches Earth, it ionizes the upper atmosphere known as the ionosphere, which can disrupt shortwave radio communications.” NASA’s SDO data confirmed the timing and intensity of both flares. Solar physicist Ryan French highlighted that the events represent the strongest X-class activity observed in the last 78 days.
Conflicting Reports & Gaps
The primary discrepancy lies in the classification of the first flare—X2.4 versus X2.5. Additionally, while CMEs were detected, their exact direction and potential geomagnetic impact remain unverified, leaving uncertainty about possible auroral displays.
What’s Next
NOAA and NASA will continue modeling the CMEs’ paths and monitoring ionospheric conditions. Forecasts will assess the likelihood of geomagnetic storms and auroral activity in the coming days, while the Sun’s progression through its current cycle will be tracked for further flare activity.
