Tea at Trianon: The Merging of Stars

John Wilson Croker on Marie-Antoinette

"We have followed the history of Marie Antoinette with the greatest diligence and scrupulosity. We have lived in those times. We have talked with some of her friends and some of her enemies; we have read, certainly not all, but hundreds of the libels written against her; and we have, in short, examined her life with– if we may be allowed to say so of ourselves– something of the accuracy of contemporaries, the diligence of inquirers, and the impartiality of historians, all combined; and we feel it our duty to declare, in as a solemn a manner as literature admits of, our well-matured opinion that every reproach against the morals of the queen was a gross calumny– that she was, as we have said, one of the purest of human beings."

~from History of the Guillotine by John Wilson Croker, 1844

Edmund Burke on Marie-Antoinette

"It is now sixteen or seventeen years since I saw the queen of France, then dauphiness, at Versailles; and surely there never lighted on this orb, which she hardly seemed to touch, a more delightful vision. I saw her just above the horizon, decorating and cheering the elevated sphere she had just begun to move in, glittering like a morning star full of life and splendor and joy. Oh, what a revolution....Little did I dream that I should have lived to see such disasters fall upon her, in a nation of gallant men, in a nation of men of honor and of cavaliers! I thought ten thousand swords must have leaped from their scabbards, to avenge even a look which threatened her with insult. But the age of chivalry is gone; that of sophisters, economists, and calculators has succeeded...."

~Edmund Burke, October 1790

Sunday, February 9, 2020

The Merging of Stars

From Ars Technica:

We know two facts about our galaxy that are, in isolation, mundane. One is that many stars are part of a two-star system and may orbit each other at distances similar to those of the planets in our own Solar System. The second is that stars that are similar in mass to the Sun will end their fusion-driven existences by expanding into bloated red giants. Put those two facts together and you have an inescapable and intriguing consequence: a lot of stars are going to end up expanding enough to swallow their neighbor.

What happens then can be hard to understand, in part because there are so many potential options. If the companion star is massive enough, the transfer of mass could trigger its explosion. It's also possible that friction could bleed energy from the orbit of the companion star, reducing its orbit until it is merged. Or, because the outer layers of the red giant are so diffuse, it's possible that the cores of the two stars could end up sharing a single envelope, continuing to orbit each other. (Read more.)