No November Nova

The nova anticipated in Corona Borealis has not yet appeared as November 2024 ends. Every 80 or so years the binary star T Coronae Borealis (T CBr) brightens enough to become visible to the naked eye. On most clear nights since mid-June 2024 I have tried to photograph the starfield containing the paired white dwarf and red giant, hoping to catch the nova emerging from the darkness.

As we segue into winter, the constellation appears close to the murky horizon in the western twilight and is difficult to see for most observers. T CBr will soon fully disappear from the convenient evening sky but has reemerged in the eastern morning sky. Hopefully the nova does not explode while it's out of sight for us earthbound observers.

Observation reports by members of the American Association of Variable Star Observers (AAVSO) reveal a running graph of the star's magnitude. Through November they are reporting a consistent brightness several magnitudes fainter than the naked eye can see.

When it eventually blows, astronomers expect a temporary (days to weeks) brightness of around mag=3, or as bright as the stars Polaris or Gemma.

Below are 83 images I've taken of the constellation Corona Borealis with a cell phone camera starting June 18, 2024, through November when the nights have been clear. A string of good viewing in October segued into a mostly cloudy late November around the Great Lakes.

Only two known recurring novae rise to the level of being visible, in part because the span between the respective events in observed single novae is usually much greater than 80 years, often in the thousands of years. Many more recurring novae likely occur, but we haven't seen their "second" appearance yet. T CBr has been sighted in 1217, 1787, 1866, and 1946.

T CBr is about 3,000 light years away. If it has been shedding the light of a nova every 80 years, then there should be a train of about 37 events en route, with one pulling into the station imminently.

While astronomer Jim Kaler anticipated (in 2011) its reappearing in 2026 after another 80-year cycle, a recently observed "pre-eruption dip" suggested we would instead have a summer 2024 interloper in the night sky. That dip announcement triggered the observing marathon. Fraser Cain explains what's happening in the opening story of this Space Bites.

As I wrote earlier, "It's possible the nova won't arrive [in 2024] as predicted...Kaler would often caution that 'nobody really knows for sure.' Astronomers are quick to recognize that the universe deviates from expectations."

If you don't seek you won't find. Well, through November 2024 I have not found.