On September 1, 2026, the ATLAS survey detected the initial spark of a brand-new supernova, SN 2026aaiv.
This Type Ia supernova detonated within the spiral arms of NGC 7331—the Deer Lick Galaxy in the constellation Pegasus. A runaway thermonuclear explosion some 40 million light-years away, it has rapidly brightened over the past week. If you’d like to explore the host galaxy in more detail and sketch from years earlier, be sure to check out my dedicated NGC 7331 page on this site.
Supernova SN 2026aaiv
A Type Ia explosion isn’t like a typical core-collapse supernova, which marks the dramatic death of an isolated giant star running out of fuel and caving in on itself. Instead, it starts with a white dwarf, a super-dense leftover core of a sun-like star, crammed down to the size of Earth. On its own, a white dwarf would cool off over billions of years. But when it orbits closely with a companion star, its gravity acts like a siphon, pulling gas from its neighbor.
As the white dwarf feeds, it gets heavier and hotter. Eventually, it reaches a tipping point. The instant it crosses that line, the star’s carbon core ignites like a giant thermonuclear bomb. In a matter of seconds, the white dwarf is completely blown to bits. The explosion can outshine the hundreds of billions of stars in its own host galaxy.
My Observations
Tonight offered one of the few clear breaks in the sky I’ve had this summer in southwest Florida. My original plan for the evening was to sweep through the southern horizon, but as word broke about the new supernova, I had to pivot. You simply don’t pass up the opportunity to catch an exploding star in real time.
Because it’s a Type Ia, there’s a good chance it will continue brightening over the coming days. If the Florida weather cooperates, I’ll be out tracking its progress throughout the week and updating this post with fresh data.
Here is tonight’s capture, straight from the garden with the Seestar S50:
Date: September 6, 2026
Location: Tampa, Florida
Time: 9:50 p.m. ET
Imaging Time: 35 minutes (Haze became heavier off the Gulf, so stopped exposing)
Sources and Notes
Banner photo of Caldwell 30: Adam Block/Mount Lemmon SkyCenter/University of Arizona. This file is licensed under the Creative Commons Attribution 3.0 Unported license.
Photo by Wayne McGraw