[♪ INTRO] If you’ve heard only one  piece of space news this year, it’s probably that the James Webb  Space Telescope is hard at work, delivering science and  breathtaking views of the universe.

It’s going to usher in a  whole new era of astronomy. But Webb is far from the only  space news that happened this year, and we’d like to highlight three  stories you may have missed.

We’re going to start a bit zoomed out… far enough to get a view of the whole Milky Way. Back in August, scientists  revealed the first map of what they call the “galactic underworld”... a galaxy-sized graveyard populated  by neutron stars and black holes, the remnants of supernova explosions. Yeah, the news did come out a  bit too early for Spooky Season.

Supernovas tend to happen in  the regions of the Milky Way known as the bulge and the disk. Because that’s where most stars form. And you need stars to make supernovas.

But stars don’t explode in perfect spheres. Any kind of matter or pressure imbalance will shoot the remnant off into  the unknown like a rocket. Until now, scientists hadn’t  tracked where those neutron star and black hole “rockets” ended up.

But one group of researchers  took on the challenge. To construct their map, they simulated  the lives of over 400,000 stars and tracked them post-supernova  to see where they ended up. And the resulting graveyard didn’t  look quite like what they expected.

The Milky Way’s distribution of dead stars doesn’t match its distribution of live stars. In fact, the graveyard  doesn’t even have spiral arms. But that’s probably because  these remnants are rocketing off in mostly random directions, which  erases a lot of the spiral structure.

Also, many of these remnants were created when the Milky Way was billions of years younger. Galaxies evolve, so the Milky Way didn’t have the same distribution of stars as it does today. The map also revealed how  much bigger the graveyard is than the galactic bulge and disk.

If you look at the galaxy edge-on,  most of the remnants are spread across a band that’s three times taller  than where living stars are found. But here’s the spookiest revelation. Roughly one third of the  remnants turned into ghosts.

They vanished from the map entirely. The team believes that a  supernova’s position in the galaxy, as well as subtle variations  in the explosion itself dictate whether or not a remnant will be  completely ejected from the Milky Way. Now, even though it’s based  on real astronomical data, this map is constructed from a simulation.

It’ll take way more powerful  telescopes than we currently have to create the first true map  of the galactic underworld. So we can’t take a tour quite yet, but  this research is a solid step forward in the quest to understand our galactic home. If we zoom in on the center of our galaxy,  we’ll see the subject of our second story.

Back in May, astronomers released  an image of the Milky Way’s supermassive black hole known as Sagittarius A*. Well, it’s an image of the  shadow around the black hole, because that’s the closest  physics will ever let us get. Sagittarius A* is now the second black hole shadow that scientists have been able to resolve.

The first belonged to the black  hole at the center of galaxy M87. You may even remember when its image was released back into the public in 2019. We certainly covered it!

The data for both images were collected in 2017. So why did it take so much longer for scientists to release the one for our black hole? It’s millions of light years closer,  but it’s also 1500 times less massive.

And less massive means the disk of  matter surrounding the black hole orbits much faster…making the  image come out much more blurry. So scientists had to invent  entirely new computer models and algorithms to compensate. And all that hard work paid off.

In addition to the image of a pretty orange donut, the Event Horizon Telescope  Collaboration published 10 scientific papers on black  holes and imaging technology. Some of the research confirmed  what scientists thought we knew, like how big black hole shadows  should be, and some revealed our models of the environment around  a black hole are incomplete. So the investigations continue.

Not just of Sagittarius A*, but  black holes throughout the universe. Astronomers also used new computer  models for our final story. Zooming into our own planetary  system, a paper published in October proposes that the Moon may have  formed in just a few hours.

If that sounds ridiculously  fast to you, you’re not alone. Previous estimates suggest it  took months if not decades. The most widely accepted  hypothesis for how the Moon formed basically goes like this: a massive  object collided with a baby Earth, causing a spray of debris that  eventually coalesced into our satellite.

Traditionally, the debris has to settle  into something like a ring of particles before it eventually collapses into one  big ball, which eats up a lot of time. But one research team proposes that  the Moon went through single-stage formation, meaning it went directly  from debris spray to celestial body. Now, the team didn’t start  their research as champions of some pre-existing single-stage  formation hypothesis.

They were just trying to figure  out what scenarios scientists should consider when investigating  the Moon’s formation. And to do that, they used a brand-new  computer model that treated the Earth, the object that smacked into Earth, and the Moon like collections of 100 million tiny particles. That’s about 100 times more  particles than most simulations keep track of when modeling  the Moon’s origin story.

And that extra level of detail  provided some curious results. After testing over 400 impact scenarios  involving different angles, speeds, and variations on how head-on the collision  was, they realized that not only was an hours long single-stage formation  possible, it was probable.,   And this isn’t just a quirky simulation result. A super quick formation  would actually help explain a few things about the Moon, like  its tilted orbit and thin crust.

But right now, the whole thing is just a proposal. In order to move forward with the idea  that the Moon formed this rapid way, we would need to find physical  evidence in rock samples. Until then, it’s kinda fun to imagine an  alien astronomer watching a baby Earth, deciding to take a nap, and then waking  up to find there was a whole Moon there.

So here’s to all the research  astronomers did this past year, regardless of how many pretty  space pics go along with it. And here’s to all of you. We can’t thank you enough for your support.

And if you’re hungry for even more  2022 space news you missed because you were busy looking at Webb’s  pretty space pictures, stay tuned. We’ve got another round-up coming out next week. [♪ OUTRO]