There was enough happening on Earth to keep us occupied this week, but don't forget to look up once in a while. Here's everything galactic you missed during Halloween and early voting.
Two historic NASA missions ran out of fuel this week: the 11-year Dawn mission to explore the two biggest objects in the asteroid belt and the nine-year Kepler Space Telescope mission that discovered thousands of exoplanets.
Although both mission conclusions were expected, it's sad to see them come to an end. Luckily, the data they provided will lead to discoveries for years to come. And neither is on a collision course with Earth. Dawn will orbit the dwarf planet Ceres for decades, and Kepler is 94 million miles away.
Farewell, brave voyagers, and thanks for all the science.
But let's give the Parker Solar Probe a hearty cheer for breaking a record and coming closer to the sun than any other spacecraft.
Hubble's awake; Opportunity isn't
Despite our letter to the Mars Opportunity rover, it still hasn't awakened and responded to NASA's many messages since it became shrouded in a planet-encircling dust storm that began in May.
NASA will continue to send more messages, and scientists hope that increasing winds will knock the dust off of Oppy's solar panels.
Meanwhile, NASA's Hubble Space Telescope is back in business and making observations again.
A gyro, or device that measures the speed at which the spacecraft is turning, had failed. This meant Hubble couldn't turn and lock on to new targets. A backup gyro turned out to be no help when it malfunctioned as well.
The backup was recovered, so expect more gorgeous images from the famed space telescope.
NASA's Chandra X-ray Observatory, which also had a gyro issue recently, is also back up and running.
Shadows in space
Speaking of Hubble, the space telescope captured an image called a bat shadow 1,300 light-years away in the stellar nursery known as the Serpens Nebula.
So what is it? A sun-like star, HBC 672, is surrounded by a big dusty debris ring. But Hubble can't see that ring. Instead, it's capturing the shadow of the ring created by the star's bright light. NASA scientists compared the large shadow to what happens when something small crosses in front of a flashlight beam.
"This is an analog of what the solar system looked like when it was only 1 or 2 million years old," explained Klaus Pontoppidan, an astronomer at the Space Telescope Science Institute. "For all we know, the solar system once created a shadow like this."
Don't get too close
If you were in space, the last thing you'd want to get too close to is a black hole, the terrifyingly destructive and insatiable garbage disposals of the universe. Once you're near one, you're really past the point of no return.
Many astronomers assume that a supermassive black hole is at the center of the Milky Way, our galaxy. That's because they tend to lurk at the center of other galaxies, too.
But for the first time, material has been seen circling the drain, so to speak. The European Southern Observatory's GRAVITY instrument observed bright radiation flares around the disc belonging to Sagittarius A, this massive object at the galactic center.
"It's mind-boggling to actually witness material orbiting a massive black hole at 30% of the speed of light," said Oliver Pfuhl, a scientist at the Max Planck Institute for Extraterrestrial Physics.
It makes for a trippy image, too.
A Milky Way of stars
Have you ever wondered why there are so many stars in our galaxy? It turns out that the Milky Way's halo was gifted -- well, kind of.
Galaxies aren't exactly friendly neighbors in the universe. Instead, they tend to merge or cannibalize one another. The Milky Way is one of the largest galaxies, and astronomers are trying to figure out whether it grew after many small mergers or just a few large ones. Sometimes, the evidence of these mergers can be found using "galactic fossils" or just following an unusual stream of stars.
New data from the Gaia satellite mission, published this week, revealed that 10 billion years ago, the Milky Way merged with another large galaxy, Gaia-Enceladus. The stars from that galaxy make up most of the Milky Way's halo and helped shape its thick disk.
The stars donated by the merger stand out from the "native stars" of our galaxy because they're younger, the researchers said.
And in about 4 million years, the Milky Way will collide with the neighboring gigantic Andromeda galaxy. So there's that to look forward to.
After two years of trekking through space for a date with an asteroid, NASA's OSIRIS-REx spacecraft is sending images of the primitive asteroid Bennu.
The spacecraft and asteroid will have their official rendezvous in December. And then we'll have some photos with color filters on them. Can't wait to see the Instagram of that date.
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