Every morning at five o'clock, composer (作曲家) Walter Werzowa would sit down at his computer waiting for a particular daily e-mail. It came from a team that had been working all night to draft Beethoven's unfinished 10th Symphony. The e-mail contained hundreds of versions, and Werzowa listened to them all, looking for the perfect tune—a sound that was unmistakably Beethoven. But the phrases he was listening to weren't composed by Beethoven. They were created by artificial intelligence.

When Ludwig van Beethoven died in 1827, he left behind some musical drafts and notes. There was barely enough to make out a phrase, let alone a whole symphony. But that didn't stop people from trying.

Werzowa and a group of music experts and computer scientists teamed up to use machine learning to create the symphony. Ahmed Elgammal led the AI side of the team. The team's first task was to teach the AI to think like Beethoven. To do that, they gave it Beethoven's complete works, his drafts and notes. They taught it Beethoven's process—like how he went from four notes to his entire Fifth Symphony. Then they taught it to compose a bridge between two sections. With all that knowledge, the AI came as close to thinking like Beethoven as possible. But it still wasn't enough. The AI doesn't really produce something that can continue for a long time and be consistent. So the team had to put the selected pieces together to build a symphony.

Matthew Guzdial researches creativity (创造力) and machine learning at the University of Alberta. He didn't work on the Beethoven project, but he says, "Modern AI, modern machine learning, is all about just copying small local patterns. And it's up to a human to then take what the AI outputs and find the genius (天资). The genius wasn't in the AI. The genius was in the human who was doing the selection."

Two powerful NASA telescopes have detected the oldest and most distant black hole ever found. Data collected via energetic X-rays by the Chandra X-ray Observatory and James Webb Space Telescope has helped astronomers spot the signature of a growing black hole within the early universe just 470 million years after the big bang, which occurred 

13. 8 billion years ago. The discovery, described in a study published in Nature Astronomy, may help astronomers figure out how some of the first supermassive black holes formed in the universe. 

"We needed Webb to find this remarkably distant galaxy (星系) and Chandra to find its supermassive black hole, " said lead study author Akos Bogdan, in a statement. "We also took advantage of a cosmic magnifying glass (宇宙放大镜) that boosted the amount of light we detected. " He was referring to an effect called gravitational lensing (引力透镜效应), which occurs when closer objects act like a magnifying glass for distant objects. Gravity essentially twists and strengthens the light of distant galaxies in the background of whatever is doing the magnifying, enabling observations of otherwise invisible features.

Astronomers detected the black hole in a galaxy called UHZ

1. At first glance, the galaxy appeared in the same direction as a cluster of galaxies known as Abell 2744, which is located about 

3. 5 billion light-years from Earth. But data collected by the Webb telescope showed that UHZl is actually much farther away and located beyond the cluster at 

13. 2 billion light-years from Earth. 

The team used the Chandra Observatory to detect superheated gas releasing X-rays within UHZ1, the obvious sign of a supermassive black hole growing in size. The detection was made possible by the Abell cluster of galaxies, which intensified the light of the UHZ1 galaxy and the X-rays released by the black hole by a factor of four. 

Astronomers think the discovery will help them better understand how supermassive black holes appeared and reached their huge masses so soon after the beginning of the universe. 

Children's museums become an essential part of our play menu. Here are 4 famous muse-ums for families.

KidsQuest Children's Museum

It features huge windows, beautifully designed exhibits and an adventurous, two-story rope ladders in the opening gallery. Kids of all ages will love building with real tools in the re-cycled room, running the cash register, doing physics experiments on water in the Water Lab and much more. Reservations are required. You can make them online.

Imagine Children's Museum

Imagine Children's Museum's new 33,000-square-foot expansion doubles the museum's previous play space and its shows. At over 60,000 square feet, its current area is much bigger than other local children's museums (which average around 10,000-20,000 square feet). Visitors can spend hours in the museum.

Children's Museum of Tacoma

At 10,000 square feet in size, the Children's Museum of Tacoma has a huge draw. Since it opened about a decade ago, it has offered pay-as-you-will admission and has no plans to change that anytime soon. This means that you can stop off for an hour, without worrying about whether you've gotten your money's worth.

Seattle Children's Museum

This kid-favorite spot is located on the lower level of the Seattle Center Armory building. Long-time museum lovers will notice a new exhibit, a post office where kids can weigh packages and slide behind the driver's seat to make pretend deliveries.