Entry #8, New Stars or Old Friends?

Image Source: National Geographic

Approximately 800 years ago, a European monk documented the arrival of a new star in the night sky, about as bright as Polaris, the "North Star." This came as a shock to early observers as this phenomenon had never been documented before. Without the knowledge of astrophysics, this premodern scientist jotted down his observation in his notes, that this was a mystery to be unravelled by future astronomers. He wasn't the last to observe this anomaly. This same star emerges and then vanishes approximately every 80 years. And that is because this isn't a star in the traditional sense. What that monk observed, centuries ago, was a thermonuclear explosion which detonated over 3,000 lightyears away: T Coronae Borealis.

Within the next few months, you can expect to see this same flare in the night sky with the naked eye. Like an enormous clock, this ticking time bomb is set to explode this year, between now and September. So keep your eyes peeled! Thanks to modern science, we now know that T Coronae Borealis, or T CrB, is not actually a star continuously being reborn and dying. It is a system of stars containing a red giant, approximately the same size as our sun, and a white dwarf, a dead star about the size of Earth but with mass comparing to that of the red giant. The two stars orbit one another every 228 days, all the while the hot white dwarf steals materials from the cool red giant. Once the white dwarf has inhaled enough matter, the combination of heat and pressure causes a runaway thermonuclear reaction, comparable to a million hydrogen bombs... BOOM!!! This is called a nova.

Image Credit: NASA Blogs

Why is this important?

T CrB is one of only ten recurring nova in our galaxy, that we are aware of. This once-in-a-lifetime opportunity will give astronomers around the globe an opportunity to study novae in a way that has never been done before. It has also been theorized that this particular type of explosion is what fertilizes the galaxy with the chemical components that lead to life. How cool is that? Since the last observation of T CrB in 1946, astronomy has progressed leaps and bounds, and the capabilities of our global observatories will surely bring new data that can lead to answering some of the biggest questions in modern-day science.

Where will it be?

A chart of the Northern Crown constellation, with T CrB depicted as the brightest light. Image Source: Medium

Thankfully, the T CrB nova will be so bright that you can observe it without any optical appendages. It can be found in the Northern Crown constellation which is in the northwestern direction from Phoenix at night, and about two full fists (yes I mean your hands) up from the horizon. Personally, I will be traveling from my ground-level, suburban dwelling up to the peak of Black Mountain with my telescope. As always, the darker the skies, the better the observation. While we do not know the exact date that the nova will occur, you will have several days to get a good look at it, before the light dims down and the two stars go about their volatile relationship.

As science moves us forward, it can be a fun exercise to look back at archaic perceptions of the cosmos. 800 years ago when the first documented observation of T Coronae Borealis was made, human beings were obsessed with paranormal implications of sudden changes in the stars. Something like the sudden arrival of a bright star might have caused fear and panic amongst early astronomers. But we now know that the vast distances of space and time allow for us to comfortably observe these fascinating phenomena. I hope you are as excited as I am, and curious enough to take a peek yourself.

"The most beautiful thing we can experience is the mysterious. It is the source of all true art and science. He to whom the emotion is a stranger, who can no longer pause to wonder and stand wrapped in awe, is as good as dead —his eyes are closed." - Albert Einstein