Eta Carinae

The universe is amazing. The more you learn about it, the more you realize how absolutely, unbelieveably amazing it is. A related amazing thing is that these days you can learn about the universe from the comfort of your living room or study.

This may seem unrelated to what has been a major focus of this blog recently but actually it is related. I will point out the connection later. For now, let’s talk about Eta Carinae, which xkcd notes (click on the image above) is a luminous blue hypergiant with anomalous Fe^II emission spectra.

Wiki provides details about Eta Carinae. “The two main stars of the Eta Carinae system have an eccentric orbit with a period of 5.54 years. The primary is a peculiar star similar to a luminous blue variable (LBV) that was initially 150–250 M_☉ of which it has lost at least 30 M_☉ already, and is expected to explode as a supernova in the astronomically near future. This is the only star known to produce ultraviolet laser emission. The secondary star is hot and also highly luminous, probably of spectral class O, around 30–80 times as massive as the Sun. The system is heavily obscured by the Homunculus Nebula, material ejected from the primary during the Great Eruption. It is a member of the Trumpler 16 open cluster within the much larger Carina Nebula.”

“Astronomically near future” means a few million years — none of us will be around to watch the supernova in Eta Carinae. Actually, human beings will not be around then. Humans would have evolved (artifically) into something that we cannot imagine. But let’s move on.

Here’s an image of the supergiant. “A huge, billowing pair of gas and dust clouds are captured in this stunning NASA Hubble Space Telescope image of the supermassive star Eta Carinae. … The resulting picture reveals astonishing detail. Even though Eta Carinae is more than 8,000 light-years away, structures only 10 billion miles across (about the diameter of our solar system) can be distinguished. … A sequence of eight exposures was necessary to cover the object’s huge dynamic range: the outer ejecta blobs are 100,000 times fainter than the brilliant central star. Eta Carinae was the site of a giant outburst about 150 years ago, when it became one of the brightest stars in the southern sky. Though the star released as much visible light as a supernova explosion, it survived the outburst. Somehow, the explosion produced two polar lobes and a large thin equatorial disk, all moving outward at about 1.5 million miles per hour. … Estimated to be 100 times more massive than our Sun, Eta Carinae may be one of the most massive stars in our Galaxy. It radiates about five million times more power than our Sun. The star remains one of the great mysteries of stellar astronomy, and the new Hubble images raise further puzzles.”

That’s a lot of text. Lots of millions and billions. It makes you feel small. But wait, there’s more. Here’s a video that puts our world in perspective.

Jupiter is the largest planet in the solar system. It’s a gas giant. It’s big but not big enough to be a brown dwarf; it’s a sub-brown-dwarf. And a brown dwarf is too small to be a real star.

The xkcd image at the top of this post nicely summarizes quite a bit of the material covered in the Kurzgesagt video above. But wait, there’s more. Here’s a video from the Nasa Goddard channel which is beautiful. It was published in July 2019.

That wraps up a brief review of some of the material available on the web related to Eta Carinae. If you cared to watch the videos and read the related links, in about a half hour you’d have learned a good deal about one tiny aspect of the universe.

Our world has changed significantly. Just a generation ago — 30 years ago — nobody had access to what you learned just now. Today, billions of people have access to a virtually infinite amount of high-resolution audio, video, text and graphics information. That has implications for teaching and learning. Any education system that does not evolve to reflect this changed circumstances is doomed to oblivion. Any nation that continues to use the outdated paradigm is similarly doomed. Which takes us back to our topic of why India’s education system has to be freed from the control of the Indian government. In the next post, I will continue the series “This Policy, Alone.”