Einstein Probe Sees Ancient X-Ray Burst Over 12 Billion Light Years Away

Image from SciTech

Most X-Rays Ever Observed

In August 2024, the Einstein Probe (EP) recorded a soft X-ray burst called EP240315a from around 12.5 billion light-years away—one of the most distant ever detected.

The burst itself lasted for over 17 minutes, and interestingly enough, the X-ray and gamma-ray signals had a multi-minute time gap in between. That is not common and contradicts typical gamma burst models.

The event lends itself to reexamination of the way energy releases progress in the early universe. EP sensitivity is proving to be valuable in the detection of distant and rare transients.

What Scientists Learn from This Burst

High-energy astrophysics and cosmology have information in the time delay about intervening matter, magnetic fields, and particle acceleration mechanisms. It can be employed to confine jet physics and gamma ray burst models.

By reaching out to such large distances, Einstein Probe's lines of sight pierce early universe conditions—when galaxies were young and the environments were diverse. Every distant burst glows as a beacon into cosmic history.

This finding also has an effect on detector design and multiwavelength follow-ups: whenever X and gamma signals do not perfectly overlap, it means more complex emission geometry or propagation effects. Future missions can be optimized to tune to pick up such mismatched events.