Alpha Centauri - Blog Posts
Alpha Centauri: The Closest Star System Image Credit & Copyright: Telescope Live, Heaven's Mirror Observatory; Processing: Chris Cantrell
Cosmic Couples and Devastating Breakups
Relationships can be complicated — especially if you’re a pair of stars. Sometimes you start a downward spiral you just can’t get out of, eventually crash together and set off an explosion that can be seen 130 million light-years away.
For Valentine’s Day, we’re exploring the bonds between some of the universe’s peculiar pairs … as well as a few of their cataclysmic endings.
Stellar Couples
When you look at a star in the night sky, you may really be viewing two or more stars dancing around each other. Scientists estimate three or four out of every five Sun-like stars in the Milky Way have at least one partner. Take our old north star Thuban, for example. It’s a binary, or two-star, system in the constellation Draco.
Alpha Centauri, our nearest stellar neighbor, is actually a stellar triangle. Two Sun-like stars, Rigil Kentaurus and Toliman, form a pair (called Alpha Centauri AB) that orbit each other about every 80 years. Proxima Centauri is a remote red dwarf star caught in their gravitational pull even though it sits way far away from them (like over 300 times the distance between the Sun and Neptune).
Credit: ESO/Digitized Sky Survey 2/Davide De Martin/Mahdi Zamani
Sometimes, though, a stellar couple ends its relationship in a way that’s really disastrous for one of them. A black widow binary, for example, contains a low-mass star, called a brown dwarf, and a rapidly spinning, superdense stellar corpse called a pulsar. The pulsar generates intense radiation and particle winds that blow away the material of the other star over millions to billions of years.
Black Hole Beaus
In romance novels, an air of mystery is essential for any love interest, and black holes are some of the most mysterious phenomena in the universe. They also have very dramatic relationships with other objects around them!
Scientists have observed two types of black holes. Supermassive black holes are hundreds of thousands to billions of times our Sun’s mass. One of these monsters, called Sagittarius A* (the “*” is pronounced “star”), sits at the center of our own Milky Way. In a sense, our galaxy and its black hole are childhood sweethearts — they’ve been together for over 13 billion years! All the Milky-Way-size galaxies we’ve seen so far, including our neighbor Andromeda (pictured below), have supermassive black holes at their center!
These black-hole-galaxy power couples sometimes collide with other, similar pairs — kind of like a disastrous double date! We’ve never seen one of these events happen before, but scientists are starting to model them to get an idea of what the resulting fireworks might look like.
One of the most dramatic and fleeting relationships a supermassive black hole can have is with a star that strays too close. The black hole’s gravitational pull on the unfortunate star causes it to bulge on one side and break apart into a stream of gas, which is called a tidal disruption event.
The other type of black hole you often hear about is stellar-mass black holes, which are five to tens of times the Sun’s mass. Scientists think these are formed when a massive star goes supernova. If there are two massive stars in a binary, they can leave behind a pair of black holes that are tied together by their gravity. These new black holes spiral closer and closer until they crash together and create a larger black hole. The National Science Foundation’s LIGO project has detected many of these collisions through ripples in space-time called gravitational waves.
Credit: LIGO/T. Pyle
Here’s hoping your Valentine’s Day is more like a peacefully spiraling stellar binary and less like a tidal disruption! Learn how to have a safe relationship of your own with black holes here.
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Project Blue for Alpha Centauri.
One Search for Planets in The Alpha_Centauri System is: Project Blue. https://techcrunch.com/2016/10/10/project-blue-aims-to-snap-the-first-picture-of-an-exoplanet-in-alpha-centauri/
Could it be that the way to slow down before arriving at a destination Solar_System is to use Solar_Sails to Reflect Light coming from The Destination Solar_System for a Longtime before entering into The Destination Solar_System?
Just finished watching Season 2 of Good Omens. My reaction can be summed up with a single Crowley quote — “I am having a MOMENT here.”
I hate how in character it was for Aziraphale to take the Metatron’s offer to replace Gabriel. I think everyone but Aziraphale knew that there was no way in Hell that Crowley would ever want to be an angel again. Aziraphale wants nothing more than to do good and make the world a better place. And while Crowley doesn’t exactly want the world to end, he doesn’t want to be beholden to the whims of Heaven or Hell either. He just wants to run away with Aziraphale — whether that’s to London or Alpha Centauri doesn’t matter, so long as it’s him and Aziraphale together.
I also just want to say that Gabriel — I mean Jim — and Beelzebub came so far out of left field but I am HERE for it. I also appreciate that that was one of the things that gave Crowley the confidence to make his move. And boy what a move. That was honestly such an in character way for Crowley to do it — and it had to be Crowley to make that move. Aziraphale definitely wouldn’t have the confidence to be THAT bold about it.
Lastly, that CLIFFHANGER. The Metatron just casually dropping that Aziraphale is going to be preparing for the Second Coming. Once the strikes are over, I will be waiting on the edge of my seat for S3 to come out. I’m not so sure Aziraphale can truly carry out the Second Coming — not with how much love he’s developed for Earth. I can’t wait to find out how THAT turns out.